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Notes: External monitoring of uterine contractility in human labour can record contraction frequency accurately, but cannot determine true intra-uterine pressure reliably. It is therefore suitable for use in spontaneous labour where there is a need for a marker of contractions to aid in continuous fetal heart rate pattern interpretation. Intra-uterine pressure measurement can provide quantitative information more reliably over intervals of 10–60 minutes. Although active pressure values for individual contractions can vary by up to 50% when measured simultaneously by two or more intra-uterine catheters/transducers, this variation is not systematic and cumulative measures vary by less than 5%. The measurement of baseline tone is affected by variables not related to uterine activity and should therefore be excluded when quantitative measures are made.

Notes: Objective To derive a longitudinal gestational reference range for amniotic fluid index and to compare it with the established cross-sectional reference range.Design Longitudinal prospective study.Setting Liverpool Maternity Hospital and Mill Road Maternity Hospital, both teaching hospitals in central Liverpool.Subjects One hundred and fifteen pregnant women, in whom the expected date by the last menstrual period and ultrasound scan at 18 to 19 weeks were in agreement by seven days, were recruited. They were divided into two groups and scanned at four weekly intervals as follows: Group A: scanned at 20, 24, 28, 32, 36, 40; and Group B: scanned at 22, 26, 30, 34, 38, 42.Results Amniotic fluid index varies with gestation, rising from early gestation to peak at 30 weeks and then falling from 36 to 42 weeks. Comparison of our reference range with that of Moore and Cayle (1990) shows obvious differences at the lower limit.Conclusion We have established a normal longitudinal reference range for the amniotic fluid index. Our ranges, derived from longitudinal data, would seem a more appropriate reference than the established reference ranges derived from cross-sectional data. In particular, the differences at the lower limits may have considerable clinical implication in the use of amniotic fluid index in the prediction of fetal compromise.

Notes: Objective To study the effect of daily treatment with 50 mg of aspirin (ASA) on the hypertensive pregnancy complications and on the production prostacyclin (PGI2) and thromboxane A2 (TxA2) in high risk pregnant women and their infants.Design Placebo controlled prospective study.Setting Departments of Obstetrics and Gynaecology, University of Helsinki, University of Oulu and Central Hospital of Middle Finland, Finland.Subjects Two hundred and eight pregnant women with pre-existing hypertension or a history of severe preeclampsia in their previous pregnancy. Prostanoids were studied in a subgroup of 18 women.Interventions The women were randomised to receive ASA (50 mg/day, n= 103) or placebo (n= 105) from the mean of 15 weeks gestational age to delivery. The exacerbation of pre-existing hypertension or the appearance of hypertension in previously normotensive women, the appearance of proteinuria and fetal growth were the main end points, but some other clinical characteristics were also recorded. Urinary excretion of PGI2 and TxA2 metabolites by mothers and infants and their production in umbilical arteries in vitro were also studied.Results Two women (one in both groups) had miscarriages, and one pregnancy was terminated for fetal anencephaly (ASA group). In addition, seven women discontinued the treatment due to urticaria (two women in ASA group), increased activity of aspartate amino tranferase in serum (one woman in both groups), or increased bleeding time (one woman in ASA group, two women in placebo group), and one woman in the placebo group was lost from follow-up. Thus the end points could be assessed in 97 women taking ASA and 100 women taking placebo. ASA did not diminish the rate of the rise of blood pressure without (12 vs 14, respectively) or with proteinuria (9 vs 11), but fetal haemodynamic disturbances as assessed by Doppler equipment (1/44 vs 6/45 women studied, P= 0.05) and need for treatment in neonatal intensive care unit (10 vs 21, P= 0.04) were more rare in ASA group. ASA tended to increase the birthweight of the newborn (3348 ± 707 g vs 3170 ± 665 g, mean ± SD, P= 0.07), but two perinatal deaths occurred in ASA group. ASA prolonged the bleeding time of the mother (435 s, 210–998 s (geometric mean, range) vs 349 s, 210–690 s, P= 0.02), but caused no extra blood loss during delivery, nor affected neonatal hemostasis. In a subgroup of mothers (ASA, n = 10; placebo, n = 8), ASA inhibited more than 90% of platelet TxA2-production, and caused a 65 to 80% decrease in the urinary excretion of TxA2 metabolites, but no decrease in the urinary excretion of PGI2 metabolites.Conclusions ASA did not prevent the rise of maternal hypertension, but improved fetal haemodynamic performance and reduced the need of intensive neonatal care. It inhibited strongly maternal thromboxane A2 but not PGI2 production and thus shifted the balance between PGI2/TxA2 to the dominance of the vasodilatory, anti-aggregatory side.

Notes: Objective To investigate the effect of cordocentesis on the umbilical and fetal cerebral circulation.Design Cross sectional study.Setting Department of Obstetrics and Gynaecology, Regional Referral Centre for Fetal Medicine, Klagenfurt Hospital, Austria.Subjects Thirty pregnant women undergoing diagnostic cordocentesis at 18 to 38 weeks' gestation.Interventions The pulsatility index (PI) in the umbilical artery and fetal middle cerebral artery was measured by pulsed Doppler ultrasound before and immediately after cordocentesis.Main outcome measures Change in umbilical artery PI and middle cerebral artery PI.Results Cordocentesis was associated with a significant decrease in both umbilical artery PI (median −0.18, range −2.21 to 1.5, P〈0.004) and middle cerebral artery PI (mean -0.15, SD 0.32, P〈0.03) and the decrease in umbilical artery PI was most marked when cordocentesis was performed transplacentally. In four cases, there were absent or reversed frequencies at the end of diastole (EDF) in the umbilical artery before cordocentesis, and in all cases there were positive EDF after the procedure. In contrast, one of the 26 cases with positive EDF developed reversed EDF following the procedure.Conclusions Acute alterations in the waveforms from both the umbilical and fetal cerebral circulation can be induced by cordocentesis. The decrease in resistance in the fetoplacental circulation could be attributed to the release of vasodilators, and the increase in resistance observed in some cases could be secondary to arterial vasospasm. Better understanding of the underlying mechanisms might help in making cordocentesis a safer procedure.

Notes: Objective To compare two oral contraceptive pills, both containing 150 μg desogestrel, but with either 20 μg (Mercilon®) or 30 μg (Marvelon®/Desolett®) ethinyl oestradiol (EE), regarding reliability, cycle control and side effect profile.Design A double blind, randomised, multicentre study over one year with follow up after three, six and 12 months. The women noted tablet intake and all bleedings on specifically designed diary cards.Setting University clinics, central hospitals and private gynaecological practices in Norway, Sweden and Denmark.Subjects One thousand women aged 18 to 40 years requesting oral contraceptive pills.Main outcome measures Reliability, cycle control, side effects, blood pressure, body weight and haemoglobin.Results In a total of 4543 cycles with the 20 μg EE dose pill and 4688 cycles with the 30 μg EE dose pill, the number of pregnancies ascribed to method failure were 0 and 2, respectively. Irregular bleeding (breakthrough bleeding or spotting) was signficantly more frequent with the 150/20 combination in about two-thirds of the cycles randomly distributed over the one year of the study. Mean blood pressure decreased slightly, particularly in the group on the 150/20 combination (about 1 mmHg), whereas mean body weight increased approximately 0.5 kg in the group with the 150/30 combination after 12 months. Haemoglobin did not change. Side effects other than bleeding problems were rare, but dizziness and mood changes were more frequent in the group on the 150/20 combination. Due to side effects, more women on the 150/20 combination discontinued the study during the one to three and four to six month periods, and women on this pill were also less positive about continuing the study drug at the end of the trial.Conclusions Both pills have high contraceptive reliability and are well tolerated, but with the 150/20 combination the cycle control is less effective. However, in view of the potentially increased safety profile of the 150/20 combination, many women can be expected to accept some additional discomfort due to irregular bleeding.

Notes: Objective 1. To design a device that would reduce contamination of staff during obstetric procedures. 2. To undertake clinical trials to assess the effectiveness and acceptability of such a device.Design A prospective study. The arm sleeve is made of a nonwoven material laminated on polyethylene film making it waterproof. It has an elastomeric cuff with adhesive that ensures a watertight seal between it and the glove.Setting Delivery suite in a teaching hospital.Methods Doctors and midwives were requested to wear the sleeve on top of the standard gown and gloves. Each user was assessed for blood contamination at the end of the procedure and a questionnaire detailing the extent of contamination and the views of the user was completed.Results Eighty questionnaires were completed. The contamination of arms and hands was 3.8% and 5%, respectively. Eighty-nine percent thought the sleeve had served its purpose and 76% said they would use it regularly.Conclusions The sleeve is an effective protective device which complements the glove and gown. We recommend that it should be used during all obstetric procedures.

Notes: Objective To analyse the effectiveness of antenatal care as a screening for nonsymptomatic disease and obstetrical risk conditions.Design Programme evaluation of antenatal care in a geographically based cohort.Setting Routine clinical practice in primary and specialist level of health care without intervention.Subjects One thousand nine hundred and eight women residing in one Norwegian county giving birth during a 12 month period, 1988 to 1989.Outcome measures The detection rates at the time of delivery, for women with five conditions: twin pregnancies, placenta praevia, breech presentation, small for gestational age (SGA) and pre-eclampsia.Results Two hundred and ninety-two women had one or more of the actual conditions, 124 (42%) had been diagnosed at the time of the delivery. The detection rate for SGA was remarkably low (14%). The detection rates for pre-eclampsia (75%), breech presentation (69%), placenta praevia (57%) and twin pregnancies (94%) were in the same range as results reported in the literature. The number of false positive antenatal diagnosis was insignificant.Conclusions Assessing the effectiveness of antenatal diagnosis of growth retardation is connected with major unsolved methodological problems. Clinical management of such cases may be better than indicated by the results based on the ultimate SGA classification. For important obstetrical conditions this study describes an applicable method for practical evaluation of the effectiveness of antenatal care. Areas where care could be improved are demonstrated.

Notes: Objective To assess the effect on obstetric practice of clinician access to umbilical artery Doppler ultrasound results.Design Randomised controlled trial.Setting A large teaching hospital.Subjects Two thousand two hundred and eighty-nine pregnancies defined as being at risk by referral for Doppler or fetal monitoring.Interventions Continuous wave Doppler studies of umbilical artery. Results immediately available to clinicians.Main outcome measures Fetal outcome: perinatal mortality, Apgar score and admission to the neonatal unit. Obstetric intervention: admission to hospital, induction of labour and caesarean section. Use of tests of fetal well being: cardiotocography, biophysical profile and ultrasound biometry.Results The treatment and control groups were comparable in age, parity, gestation at point of entry and risk features. There were no overall differences in perinatal outcome, obstetric intervention or use of fetal monitoring. Examination of a subset recruited only because of hypertension or suspected intrauterine growth retardation (n = 754) similarly showed no difference attributable to group randomisation. Comparison of only those pregnancies retrospectively defined as low risk and high risk showed more use of cardiotocography in the high risk group with access to Doppler (P= 0.007) but no difference in the low risk group.Conclusion Doppler umbilical artery recording has been shown to perform well in prediction power of antenatal fetal compromise. What has been examined in this study is the response of clinicians to the test. The results suggest that obstetricians do not use the test to modify their risk assessment, and, therefore, the need for fetal monitoring in particular pregnancies. There is a real need for accumulation of information from very large data sets, particularly in the prediction power of Doppler for antenatal fetal compromise from apparently chronic utero-placental cause to guide use of monitoring resources. If simply added to existing fetal monitoring techniques in a hospital where these are widely used, then umbilical artery Doppler recordings may at present simply involve extra resources of staff and expenses, without benefit.

Notes: Objective To investigate the relationship of zinc in the causation of neural tube defects and so explore the possible role as a cause of these defects.Design Stored serum samples collected as part of the Medical Research Council's multicentre randomised trial/〉 of vitamin supplementation in the prevention of neural tube defects were retrieved in respect of women who had had an affected pregnancy together with four matched unaffected controls per case. One control was selected from each of the four randomisation groups: 1. no extra vitamins; 2. folic acid supplementation alone; 3. folic acid and other vitamin supplementation; and 4. other vitamin supplementation, such that it was matched with an NTD case by study centre, maternal age (the year of birth differed at most by one year) and duration of storage of the serum sample (in most instances to within the same year).Setting A prospective case-control study using serum samples stored at -40°C. The serum samples were collected from women at entry to the trial, immediately before the women became pregnant and at about 12 weeks of pregnancy.Subjects Twenty-seven women with a pregnancy associated with a neural tube defect and 108 matched controls with unaffected pregnancies.Results There was no association between serum zinc levels and neural tube defects; the mean values in μg/dl were: 82 and 85 in cases and controls, respectively, at entry to the study; 86 and 87 μg/dl just before pregnancy; and 76 and 80 μg/dl in the first trimester of pregnancy. Folic acid supplementation did not have an effect on serum zinc levels.Conclusion Within the range of serum zinc levels observed among women in our study, serum zinc is not a cause of neural tube defects, and periconceptional folic acid supplements do not compromise the zinc status of the mother or the embryo with respect to zinc intake.

Notes: Fetal heart rate (FHR) records should be presented as measurements derived from numerical analysis. Such analysis requires computerized systems. The Oxford system is the longest established and most tested of the systems available. It could provide the basis for a standardized approach to the numerical analysis of antepartum FHR records. Intrapartum FHR monitoring is of uncertain clinical value. It is premature to recommend standards for numerical analysis to upgrade the present methods of data presentation during labour. Once the patterns of abnormality are better defined numerically such standards will be mandatory because intrapartum FHR records cannot be interpreted reliably by eye.

Notes: Objective To compare reagent strip testing (RST) with microscopy and culture in identifying significant bacteriuria, and secondly, to consider potential cost savings if RST screening proved to be reliable.Design Prospective descriptive study.Setting Antenatal Clinic, Bristol Maternity Hospital.Subjects Eight hundred and ninety-eight women having urine testing in pregnancy for microscopy and culture either routinely or because of a clinical indication.Interventions The midstream specimens of urine had RST examination using Ames Multistix 8SG prior to being sent to the laboratory.Main outcome measure Significant culture (〉105 colonies/ml) of a single organism in culture.Results The highest predictive value for a negative result of the urine culture (99.7%) was obtained when using four RSTs in combination. The RST for nitrite had a high predictive value for a positive urine culture (90%). The samples which gave a false negative result with RST screening were mainly infected with low grade urinary pathogens or genital tract contaminants.Conclusion RST screening for bacteriuria provides a reliable and cheap alternative to culture of all urine specimens.

Notes: Objective To assess the outcome of pregnancy following assisted conception.Design Cohort descriptive study.Setting Unit of Reproductive Medicine, Ninewells Hospital and Medical School.Subjects One hundred and forty-eight consecutive assisted conceptions.Main outcome measures Patient characteristics and outcome of pregnancy.Results Seventy-nine percent of mothers were aged between 26 and 35 years (mean 31.4). The main causes of infertility were tubal (48%), unexplained (35%), anovulatory (8%) and male factor (8%). Primary infertility accounted for 61% of cases and 82% of pregnancies occurred within 3 treatment cycles. Thirty-five (24%) pregnancies miscarried before 14 weeks and 7 (5%) between 15 and 24 weeks gestation. One hundred and three pregnancies resulted in 136 liveborn infants. There was one neonatal death. Thirty-five babies were admitted to SCBU. Antenatally, 13% of patients were admitted to hospital with hypertension and 8% with APH; 50% of multiple and 13% of singleton pregnancies were delivered prematurely, 68% following preterm labour. There were 28 sets of twins (four miscarried at less than 24 weeks) and four sets of triplets. Multiple pregnancy was not associated with cause of infertility, treatment, age or ovarian hyperstimulation syndrome. Seventy-eight per cent of singletons and 50% of multipara were delivered vaginally.Conclusions Our data confirm the high incidence of pregnancy loss and preterm delivery associated with assisted conception once allowing for the high rate of multiple pregnancies. The effect of assisted conception programme on health services is discussed.

Notes: Objective To determine the incidence of fetal aneuploidy in women who had unsuccessful chorionic villus sampling (CVS) procedures.Design Retrospective study.Setting Pennsylvania Hospital, Philadelphia, Pennsylvania, USA.Subjects Two thousand six hundred and sixty-eight women who underwent chorionic villus sampling, in 78 (2.9%) of whom villi could not be obtained.Interventions Sixty-nine of 78 (88%) women who had an unsuccessful CVS procedure underwent a subsequent amniocentesis later in the same pregnancy.Main outcome measures The incidence of aneuploidy identified from amniotic fluid chromosome analysis in the 69 women who had an unsuccessful CVS procedure compared to the frequency of aneuploidy in women having a successful CVS procedure.Results Of the 69 women who underwent a post-CVS amniocentesis because of failure to obtain chorionic villi, six aneuploid pregnancies were identified (8.7%). The frequency of aneuploidy in the 2590 successfully sampled CVS patients was 2.5%. This difference was statistically significant (P= 0.009) by Fisher's exact test (two-tailed).Conclusions Women having an unsuccessful CVS procedure should be informed that they may be at increased risk for carrying an aneuploid fetus.

Notes: Objective To assess the cervical response to myometrial activity in early labour.Design Prospective observational study.Subjects Women requiring oxytocin stimulation in induced and spontaneous labours.Setting A teaching hospital in Birmingham.Main outcome measures Simultaneous comparison of the cervical response to myometrial contractions was made on a cycle by cycle basis to deduce the properties of the cervix in early labour.Results Sixty-seven patients have been monitored, of whom 63 had satisfactory cervimetry data. Thirty (47.6%) women exhibited cervical contractions in response to myometrial activity. This response was only observed at dilatations up to 4 cm. The change in behaviour coincides with the transition from latent to active phases of dilatation. The length of the latent phase of labour was significantly longer in those women who exhibited cervical contractions (P〈0.001), although the active phase was similar in the two groups (P〉0.1). The group without cervical contractions exhibited a greater degree of efface-ment (P〈0.05) and tended to have more dilated cervices (P〈0.01) than those who showed cervical contractions.Conclusions It is possible for the cervix to contract in early labour. This response may be the result of incomplete preparation of the cervix for the process of dilatation, and is seen during what is recognised as the latent phase in those women in whom the cervix is uneffaced and undilated. These properties of the cervix may explain the poor results obtained from oxytocin stimulation of labour in the latent phase.

Notes: Objective To establish reference ranges for the levels of alpha-fetoprotein, albumin, prealbumin (transthyretin) alpha-1-antitrypsin, transferrin, ceruloplasmin and total protein in the plasma of normal human fetuses and newborn babies.Design Prospective study of individual normal cases to fulfil objectives.Setting Pathology laboratories of the University of Edinburgh and the biochemistry laboratories of the University of Keele.Subjects Twenty-two normal fetuses 13 to 22 weeks of gestation and 66 babies born between 24 and 41 weeks gestation.Results Albumin is the predominant plasma protein throughout gestation. The levels of alpha-fetoprotein and prealbumin fell significantly with increasing gestation, whereas the concentrations of the other proteins studied increased. The ratios of individual proteins to total protein demonstrated similar trends.Conclusions This study provides developmental profiles of normal human fetal plasma proteins to serve as possible reference data for abnormal fetuses. Declining levels of prealbumin (transthyretin) were unexpected and suggest a functional role for this protein in early pregnancy.

Notes: Objective To develop a nonpenetrating scalp electrode for intrapartum fetal monitoring.Design Preliminary observational evaluation of the device.Setting An urban academic hospital in Johannesburg, South Africa.Subjects Fifteen women in labour.Intervention Application of the electrode for intrapartum monitoring.Outcome measures Quality of tracings, duration of application, disconnection of the electrode, marking of the scalp.Results Application was successful in 13of 15 women, and high quality tracings obtained in 12.Conclusions The design of scalp electrode tested is effective and produces high quality tracings in most cases.

Notes: Objective To investigate the occurrence of invasive carcinomas following local destructive treatment for cervical intraepithelial neoplasia (CIN) and to evaluate the factors responsible.Design A multicentre retrospective study.Subjects Forty-nine women registered with the British Society for Colposcopy and Cervical Pathology from 24 centres throughout Great Britain between 1985 and 1992, who had been treated by local destructive methods for CIN and who subsequently developed invasive carcinoma of the cervix.Results Of the 49 women whose details were submitted, 42 had squamous cell carcinoma, six adenosquamous carcinoma and one adenocarcinoma. Eight had microinvasive carcinomas (Stage Ia) at the time of diagnosis, 24 had Stage Ib tumours and eight Stages II to IV. Thirteen women have died. Thirty-five women had been treated by laser vapourisation, ten by cold coagulator, two by diathermy and two by cryosurgery. In 19 women (39%) the diagnosis of invasive carcinoma was made on the first follow up visit or within one year of treatment. Five patients did not present with invasive disease until more than five years after treatment.Conclusions The data presented suggest that many, but not all, of the invasive carcinomas presenting after local destructive treatment for CIN resulted from failure to recognise early invasive disease at the time of the initial assessment. The importance of thorough evaluation before undertaking these forms of treatment is emphasised. The use of excisional procedures should further reduce the small risk of invasive carcinoma developing after treatment for CIN.

Notes: Objective To investigate the effect of laser conisation of the cervix on the outcome of subsequent pregnancy.Design Case-control study.Setting Department of Obstetrics & Gynaecology, University Hospital, Trondheim, Norway.Subjects Three hundred and fifty-one women were treated for cervical intra-epithelial neoplasia (CIN) by laser conisation of the cervix between 1 January 1983 and 31 December 1985. The 56 women among them who had been delivered of live infants beyond 22 weeks gestation after the conisation and before 1 January 1991 were studied for the outcome of their pregnancies. For each case, two controls of equal parity and age (±3 years) were selected.Main outcome measures The length of gestation and birthweight of the infants.Results The median (range) length of gestation was 39 weeks (26–43) in cases compared with 40 weeks (34–42) in controls (z=−4.0, P〈0.001). The median (range) birthweight was 3330 g (1150–4940) in cases and 3630 g (1610–5080) in controls (z=−3.5, P〈0.001). Overall 38% of cases were delivered preterm (≤37 weeks gestation), compared with 6% of controls (P〈0.0001; odds ratio 9.0, 95% CI 3.7–21.7). A logistic regression analysis of a set of possible confounding factors revealed no significant risk factors in addition to conisation for the occurrence of preterm delivery. No correlation was found between the height of the cone and the occurrence of preterm delivery in subsequent pregnancy.Conclusion Conisation with microsurgical laser technique increases the risk of preterm delivery in subsequent pregnancies. Laser conisation in young women should be restricted to those with high grade CIN or a lesion extending into the endocervical canal.

Notes: Objective To measure quantitatively and objectively the maternal and fetal tobacco exposure during pregnancy and its neonatal effects.Design Tobacco exposure was assessed from maternal serum samples, obtained during the first half of pregnancy and from umbilical serum samples obtained at delivery, by measuring the concentration of nicotine metabolite, cotinine. Data on the respective pregnancies and neonates were collected from the Finnish Medical Birth Registry.Setting Finland.Subjects One thousand two hundred and thirty-seven pregnancies and newborns, representing all pregnancies resulting in a liveborn infant during one week in one country.Main outcome measures Gestational age, birthweight and crown-heel length of newborns.Results Cotinine (〉6 μg/l) was detected in either maternal or umbilical serum in 300 pregnancies, and these mothers and newborns were classified as exposed. Important differences occurred between measured exposure and reported smoking behaviour. Of the exposed mothers, 38% were nonsmokers and 3.4% of the nonexposed mothers were smokers. Tobacco exposure was associated with shorter gestational age, reduced birthweight and shorter crown-heel length of the newborns. After correction for parity, gender, and gestational age, the exposed newborns were on average 188 g (95% confidence interval (CI) 123–253 g) lighter and 10 mm (95% CI7–13 mm) shorter than the nonexposed newborns. One μg/ml of cotinine in maternal serum resulted in a mean decrease of 1.29 g (95% CI 0.55–2.02 g) in birthweight and in a mean decrease of 0.059 mm (95% CI 0.035–0.083 mm) in birth length. Maternal cotinine concentrations better explained the neonatal findings than the reported smoking habits.Conclusions There is a quantitative dose and effect relation between tobacco exposure and a decrease in the gestational age at birth and size of the neonate. The smoking habit reported by mothers themselves is not an accurate measure of fetal tobacco exposure.

Notes: Objective To assess the ability of noninvasive tests of fetal wellbeing to predict hypoxic morbidity independent of fetal size.Design A prospectively planned, longitudinal, observational study.Setting Fetal Surveillance Unit, King's College Hospital, London.Subjects One hundred and ninety-one pregnant women with singleton pregnancies who were delivered after 32 weeks' gestation who were seen in the Fetal Surveillance Unit within seven days of delivery.Interventions Fetal surveillance by fetal abdominal circumference, heart rate variability (mean range), biophysical profile score and umbilical artery pulsatility index measurements.Main outcome measures Birthweight was classified as 〈 or ≤2.5th centile (AGA or SGA) for gestational age and sex. Morbidity was defined as at least one of the following at birth: delivery by emergency caesarean section for fetal distress, umbilical venous blood pH less than 7.15, 5 min Apgar score less than 7 or admission to the Special Care Baby Unit (SCBU).Results Fetal abdominal circumference was the best indicator of which fetuses (n = 30) would be SGA. Fourteen of the 30 (47%) SGA fetuses had morbidity at birth and abnormal umbilical Doppler studies significantly predicted this (χ2= 2.93, P= 0.003). By contrast, fetal heart rate variability and the biophysical profile score did not. Twenty-seven of the 161 (17%) AGA fetuses had morbidity at birth, but this was not significantly predicted by heart rate variability, biophysical profile score or umbilical Doppler studies.Conclusions None of the antenatal testing techniques studied predicted morbidity in normally grown fetuses but Doppler studies indicated whether a small fetus was ‘sick small’ or ‘normal small’.

Notes: Objective To investigate the role of altered innervation of the urethral sphincter in the genesis of genuine stress incontinence.Design Prospective observational study.Setting Tertiary referral centre urodynamics unit.Subjects Sixty-eight women, 33 with urodynamically proven pure genuine stress incontinence and 35 controls without urinary symptoms.Interventions Concentric needle electromyography of the urethral striated sphincter.Main outcome measures The means of motor unit potential duration, number of changes in polarity and the amplitude of individual motor unit potentials were compared between the two groups.Results There was no statistically significant difference in motor unit potential duration (P= 0.87) or in the number of changes in polarity (P= 0.85). There was a trend towards a higher amplitude of motor unit potentials in the control group (P= 0.07).Conclusions Our findings suggest that denervation and re-innervation of the striated urethral sphincter following trauma to the pelvic floor, such as that occurring during childbirth, is not a major aetiological factor in the development of genuine stress incontinence.

Notes: Objective To determine the efficacy of a new regimen of the antiprogestogen mifepristone and gemeprost for midtrimester abortion.Design Prospective study.Setting Medical Termination Unit, Simpson Memorial Maternity Pavilion, Edinburgh.Subjects One hundred women undergoing midtrimester abortion.Interventions Women were pretreated with 200 mg mifepristone 36 h before prostaglandin; 1 mg gemeprost was administered every 6 h for the first 24 h. If abortion had not occurred, 1 mg gemeprost was administered 3 hourly over the next 12 h.Measurement and main results Ninety-six percent and 99% women aborted within 24 h and 48 h, respectively. The median prostaglandin-abortion interval was significantly shorter in multigravidae compared to primigravida (6.6 vs 8.2 h, P〈0.01). The median number of gemeprost pessaries to induce abortion was only two and 47% of women required one pessary. The incidence of vomiting and diarrhoea was 31% and 5%, respectively. Eighty-four percent of women required intramuscular diamorphine for analgesia. Thirty-three percent of women required an evacuation of the uterus following abortion.Conclusions The shortened induction-delivery interval following pretreatment with mifepristone makes it possible to conduct midtrimester abortion on a daycare basis.

Notes: Objective To measure levels of folate and vitamin B12 in matched samples of amniotic fluid and extraembryonic coelomic fluid from 9 to 12 weeks' gestation.Design Prospective observational study.Setting Homerton Hospital, London.Subjects Twenty-two women with ultrasonographically normal pregnancies before surgical termination.Methods Transvaginal ultrasound-guided needle aspiration of amniotic fluid and extra-embryonic coelomic fluid was performed. Pure samples of amniotic fluid and extra-embyronic coelomic fluid were obtained from each pregnancy, and folate and vitamin B12 were measured using microbiological assays.Results Levels of folate and vitamin B12 were higher in extra-embyronic coelomic fluid than in amniotic fluid and maternal serum. Amniotic fluid folate levels were lower than in maternal serum whereas vitamin B12 levels in amniotic fluid were higher than in maternal serum. All differences in concentration were significant (P〈0.0005; paired t-Test). Positive correlations were found between the concentrations of folate and vitamin B12 in each fluid. There was a linear correlation between gestational age and amniotic fluid folate levels (r= 0.648; P= 0.001).Conclusions High concentrations of folate and vitamin B12 in coelomic fluid suggest that the coelomic cavity plays an important role in the materno-fetal exchange of these nutrients.

Notes: Objective To assess the potential benefits of using extended trained ambulance personnel (paramedics) as primary responders for domiciliary obstetric and gynaecological emergencies.Design An observational study of performance and analysis of operational data in a newly established service.Setting A mixed urban and rural population served by South Glamorgan Health Authority.Main outcome measures Work load, response times, management and transfer of patients, efficiency of communications and appropriateness of training.Results There was an initial increase in requests above that when a hospital-based service operated. Targets for response times were met. The mean response time for providing appropriate skilled help was halved compared with the previous arrangements and a safe and efficient service was provided. Prompt transport and advance notice and preparation for reception in the delivery unit contributed to optimal management. Medical staff depletion in the delivery unit was minimised.Conclusion An Emergency Domiciliary Obstetric Service based on primary response by specially trained ambulance service paramedics can beneficially replace traditional hospital-based Obstetric Flying Squads.

Notes: Objective To investigate the effects of anxiety and depression during pregnancy on obstetric complications using the data collected from the St George's Birthweight Study.Design Prospective population study.Setting District general hospital in inner London.Subjects A consecutive series of 1860 white women booking for delivery were approached. Of these, 136 refused and 209 failed to complete the study for other reasons, leaving a sample of 1515.Main outcome measure Data were obtained by research interviewers at booking, 17, 28, and 36 weeks gestation and from the structured antenatal and obstetric record. The predictor variables were the anxiety and depression scores measured using the General Health Questionnaire. The outcome variables were five obstetric complications: preterm delivery; nonspontaneous onset of labour; major analgesia in the first and second stages of labour; and nonspontaneous vaginal deliveries. The possible confounding effects of 35 socio-economic, psychological and personal variables were investigated using logistic regression.Results The factors that had the strongest relation with the outcomes were parity and maternal age. Depression during pregnancy was unrelated to the obstetric complications. Anxiety was weakly related to analgesia/anaesthesia in the second stage of labour (P= 0.04). However, anxiety accounted for only 0.1 % of the variance in use of major analgesia/anaesthesia. The most effective model, that for analgesia/anaesthesia in the first stage of labour, accounted for only 7.3% of the variance.Conclusions In the general population of pregnant women, anxiety and depression during pregnancy, while undesirable in themselves, are of little importance in the evolution of obstetric complications.

Notes: Objective To determine the normal response to a 75 g glucose challenge in the context of an oral glucose tolerance test in the third trimester of pregnancy.Design Prospective observational study.Setting Antenatal clinic, Kandang Kerbau Hospital, Singapore.Subjects Sixty-four normal pregnant women with a low risk for diabetes.Interventions Glucose (75 g) challenge following an overnight fast after 28 weeks of gestation.Main outcome measure Venous plasma glucose levels taken before and 2 h after the glucose challenge.Results Upper limits of normality were found to be fasting glucose 4·9 mmol/l and 2 h glucose 9·2 mmol/l.Conclusion The WHO (1980) criteria should not be used in pregnancy.

Notes: Objective To determine plasma phenytoin levels and seizure outcome in women given phenytoin for seizure prophylaxis in severe pre-eclampsia and eclampsia.Design Prospective observational study comparing two phenytoin loading regimens.Setting Two UK teaching hospitals.Subjects Sixty-seven consecutive women with severe pre-eclampsia and five with eclampsia.Interventions The first 29 women were given a 15 mg/kg intravenous loading dose of phenytoin. The next 43 received 17.5 mg/kg. All were given 500 mg phenytoin 12 h after completion of the loading dose and then 250 mg every 12 h for four doses.Main outcome measures Total plasma phenytoin levels at 30 min, 6 h and 12 h after loading dose, 6 h after first maintenance dose and on days 2 and 3 of maintenance therapy; eclamptic seizures after starting phenytoin.Results Mean plasma phenytoin levels were higher at 30 min and 6 h after the 17.5 mg/kg loading dose. Nine of 29 (31%) phenytoin levels 30 min after the loading dose were above the therapeutic range in the 15 mg/kg group compared with 26/38 (68%) in the 17.5 mg/kg group (P〈0.01). Six of 27 (22%) phenytoin levels 12 h after the loading dose were subtherapeutic in the 15 mg/kg group compared with 2/38 (5%) in the 17.5 mg/kg group (P〈0.05). Three women, two in the 17.5 mg/kg group, developed seizures after starting phenytoin. All three had plasma levels within the therapeutic range.Conclusions Compared with a loading dose of 17.5 mg/kg, loading with 15 mg/kg phenytoin was associated with a lower incidence of high plasma levels at 30 min but a higher incidence of subtherapeutic levels at 12 h. Seizures occur in 2 to 3% of pre-eclamptics despite apparently therapeutic phenytoin levels.

Notes: Objectives To determine how micro-invasive carcinoma of the cervix is diagnosed and treated in the United Kingdom. To record the frequency of the various pathological features which comprise the histological diagnosis of micro-invasion, and to assess their relevance to outcome.Design Prospective observational study.Setting Hospitals throughout the United Kingdom.Subjects Two hundred and eighty-six cases were submitted for entry into the study. Following independent review of the histological material 116 cases were excluded: 41 were not accompanied by histological slides for review, 55 had no evidence of invasive disease, 17 had invasive disease greater than FIGO Stage 1a, and three were adenocarcinomas. The remaining 170 cases were registered for the study but follow up was incomplete in 18. This report concerns the 152 women with complete follow up to 1991.Results The age of the 152 women ranged from 22 to 65 years (median 36 years). In 116 women (76%) the diagnosis was made by cone biopsy (cold knife, loop diathermy, or laser) or wedge biopsy, in 9 women (6%) the diagnosis was made by hysterectomy, and in 27 women (18%) punch biopsy suggested an invasive lesion and subsequent excisional treatment (including radical hysterectomy with node dissection in three) demonstrated micro-invasion. The depth of invasion was up to 3 mm in 142 women (93%) and 3.1 to 5 mm in 10 women (7%). Capillary-like space involvement was present in 12 women (8%). Treatment methods used were local cervical surgery in 79 women (52%), simple hysterectomy in 63 (41%), and radical hysterectomy in 10 (7%). There was only one known recurrence and death due to cervical carcinoma.Conclusion There is no uniformity in the management of micro-invasive carcinoma of the cervix. The frequency of recurrence, lymph metastases, and death is low. Nonradical surgery appears to give satisfactory results.

Notes: Objective To derive clinical standards for singleton birthweight in a population based on area of residence.Design Analysis of variables recorded in Aberdeen Maternity and Neonatal Databank, calculating for each birth a standardised birthweight score, taking account of determining factors.Subjects All singleton live births of 32 to 42 weeks gestation to Aberdeen City District residents from 1979 to 1983.Results Basic standards of birthweight are presented correcting for gestational age, sex of the baby and parity of the mother. Birthweight is not normally distributed and empirical data are presented rather than smoothed curves. Adjustment for maternal height is straightforward but adjustment for maternal weight must take account of the gestation at which the woman was weighed. A method of calculating the appropriate correction for height and weight is described in detail.Conclusion Birthweight is not normally distributed at each week of gestation. Standardisation for parity, gestation and sex of the baby is essential, but adjustment for maternal size is complex.

Notes: Objective To compare whole blood platelet aggregation in moderate and severe pre-eclampsia with normal pregnancy.Design Whole blood platelet aggregation in response to collagen, ADP, PAF, adrenalin and arachidonic acid was measured in the pre-eclampsia group at 36 weeks gestation and at 1, 24 and 48 h and at five days and six weeks post delivery. The normal pregnancy group were studied serially at 12, 20, 28, 32, and 36 weeks gestation and at 1, 24, 48 h and six weeks post delivery.Setting Trinity College Medical School, St James's Hospital, Dublin.Subjects Thirty women with diagnosed pre-eclampsia were recruited for the study. Fifteen of these women had severe pre-eclampsia and the remaining 15 had moderate disease. The pre-eclampsia group were compared with 20 healthy primigravid women with uncomplicated pregnancies and deliveries.Results In women with severe pre-eclampsia, platelet aggregation in response to collagen, ADP, adrenalin and arachidonic acid was significantly lower at 36 weeks gestation compared with normal pregnancy. Lower levels of collagen induced aggregation were also found at 1 h post delivery when compared with normal pregnancy. Women with moderate pre-eclampsia showed a decreased response to aggregating agents at 36 weeks gestation but this was not significant. ADP, collagen and PAF induced aggregation was higher in women with moderate pre-eclampsia at 36 weeks gestation and during the early puerperium compared with severe pre-eclampsia.Conclusions The clinical signs of pre-eclampsia are accompanied by a reduction in platelet responsiveness, the extent of which is related to the severity of the disease. This suggests that an abnormal platelet activation occurs early in pregnancies destined to be complicated by pre-eclampsia. This activation may be involved in the pathogenesis of pre-eclampsia since its inhibition using low dose aspirin has been shown to modify the disease in high risk pregnancies.

Notes: Objectives To assess the proportion of breech presentations diagnosed in labour and to compare their outcomes with those diagnosed prior to the onset of labour.Design Retrospective casenote review.Setting Mill Road Maternity Hospital, a teaching hospital in central Liverpool.Subjects Three hundred and five singleton breech presentations delivered in the hospital between January 1988 and July 1991; 226 cases prior to the onset of labour and 79 cases diagnosed for the first time in labour.Main outcome measures Rates of vaginal delivery and caesarean section, birthweight, short term morbidity as assessed by trauma, signs of cerebral irritation and admission to the newborn intensive care unit (NBICU), and Apgar scores.Results Breech presentations diagnosed for the first time in labour were more likely to deliver vaginally than those assessed and allowed to go into labour (odds ratio 1:68 95% CI 1.0–3.0). This difference was not due to demographic variables or differences in birthweight. There was no short term morbidity attributable to vaginal breech delivery.Conclusion A significant number of breech presentations are not detected until labour despite rigorous antenatal surveillance. Our results show that undiagnosed breeches may not be important as they are more likely to deliver vaginally, with no excess morbidity or mortality, compared to diagnosed breeches in labour, carefully assessed for vaginal delivery. There are, therefore, no grounds for delivering all undiagnosed breeches by caesarean section.

Notes: Objective To investigate the status of the fetal renin-angiotensin system (RAS) in pregnancies complicated by severe intrauterine growth retardation (IUGR), and its possible relationship to elevated fetoplacental vascular resistance as indicated by abnormal umbilical artery Doppler flow velocity waveforms (FVW).Design Prospective survey of pregnancies falling into predefined categories and presenting at the Queen Mothers Hospital, Glasgow, over the study period.Subjects Effects of mode of delivery and gestational age were investigated using uncomplicated term pregnancies delivered vaginally (SVD group, n= 15) or by elective caesarean section (ECS group, n= 9), and normal pregnancies with spontaneous preterm onset of labour (PREM group, n= 6; normal birthweight for gestational age (31 weeks)). These groups were used as controls for the 13 IUGR cases delivered preterm (31 weeks) by caesarean section in the fetal interest.Main outcomes measures Umbilical artery FVW, birthweight, cord venous angiotensin II concentration ([cv ANG II]), fetoplacental vascular ANG II receptor concentration.Results Cord venous angiotensin II concentration was similar to maternal values in the ECS group (31–101 pmol/1, 95% CI), but was elevated (81–288 pmol/l, P= 0.03) after vaginal delivery. The concentration of ANG II receptors (type AT1, dissociation equilibrium constant, 1.27 nmol/l) in placental primary/secondary stem vascular tissue was lower in the SVD group (18–44 fmol/mg membrane protein, 95% CI), compared with the ECS group (29–122 fmol/mg, P= 0.03) consistent with acute receptor down-regulation by the elevated ANG II levels. No effect of gestational age on receptor number was demonstrable (P= 0.13, PREM (premature delivery) vs ECS group). In the IUGR group, [cv ANG II] (94–378 pmol/l) was markedly elevated compared with the ECS controls (P= 0.001) but receptor concentration (28–84 fmol/mg) was not significantly altered (P= 0.13). No relationships between [cv ANG II] or receptor number and umbilical artery FVW could be identified. No changes in receptor affinity were observed.Conclusion These results indicate activation of the fetal RAS in IUGR and suggest that responsiveness of the fetoplacental vasculature to the peptide is not diminished as would be expected from the elevated plasma ANG II levels. ANG II may contribute to the increased fetoplacental vascular resistance observed in this disorder, but does not apparently account for the abnormal umbilical artery FVW that is observed in a proportion of IUGR cases.

Notes: Objective To investigate the value of the measurement of free β human chorionic gonadotrophin (hCG) as a serum marker of Down's syndrome in the second trimester of pregnancy.Design A prospective observational study using stored antenatal serum samples.Setting Serum samples collected from women receiving routine antenatal care in Oxford.Subjects Seventy-five singleton pregnancies with fetal Down's syndrome and 367 unaffected singleton pregnancies. Each affected pregnancy was matched with five control pregnancies for maternal age, gestational age, and duration of storage of the serum sample. None of the pregnancies were associated with neural tube defects.Main study measures Maternal serum free β-hCG levels. These were compared with total hCG levels in the same pregnancies. The performance of screening using free β-hCG was compared with that using the principal markers, namely alpha-fetoprotein (AFP), unconjugated oestriol (uE3), and total hCG together with maternal age.Results The median free β-hCG level in the affected pregnancies was 2.22 multiples of the normal median (MoM), significantly higher than in the unaffected pregnancies (95% confidence interval, 1.84–2.68 MoM). The discriminatory performances of free β-hCG and total hCG, each considered separately, were similar; with a cut-off level of 2.5 MoM the detection rate was 43% and 5.7% of unaffected pregnancies had raised free β-hCG levels (likelihood ratio of 7.5 (43/5.7)), somewhat better discrimination than the 32% and 4.6% respectively using total hCG (likelihood ratio of 7.0 (32/4.6)). With a higher cut-off level of 3.5 MoM, the rates were 19% and 2.7% respectively (likelihood ratio of 7.0), using free β-hCG, worse than the 19% and 1.4% using total hCG (likelihood ratio of 13.6). Screening using maternal age, AFP, uE3 and free β-hCG (instead of total hCG) yielded a detection rate of 62% (instead of 58%) at a screening risk cut-off level corresponding to a 5% false-positive rated).Conclusion The main advantage in using free β-hCG instead of total hCG is that there is a small increase in the detection rate (4%) for a given false-positive rate when used with maternal age, AFP and uE3. The main disadvantage is that there is less practical experience with free β-hCG measurement and insufficient data to screen in certain categories of pregnancy (e.g., twins). The best practical advice is to use total hCG for the present but consider changing to free β-hCG either (i) after further data are available that will permit the interpretation of screening results in the same way as is currently available with total hCG, or (ii) if its use with another marker confers a worthwhile increase in the detection rate for a given false–positive rate.

Notes: Objective To demonstrate the potential and effectiveness of autologous blood transfusion in an obstetric and gynaecological practice.Setting The Department of Obstetrics and Gynaecology and the department of Haematology, University College Hospital, Galway, Ireland.Subjects One hundred and sixty-eight women undergoing abdominal hysterectomy, 42 women undergoing repair procedures, and 56 women undergoing elective caesarian sections participated in this programme.Results In the abdominal hysterectomy group 329 units of blood were collected of which 48% were transfused to the donors. In the repair group 82 units of blood were collected of which 21.9% were transfused to the donors. In the elective caesarian section group 105 units of blood were collected of which 64.7% were transfused to the donors. Overall the donation procedure was well tolerated with infrequent donor reactions.Conclusion Our experience demonstrates that autologous blood transfusion is a safe and reasonable transfusion practice in the setting of obstetrics and gynaecology.

Notes: Objective To investigate the effect of induced abortion on subsequent fertility.Design 1. Prospective cohort study of women who had an unplanned pregnancy at recruitment. 2. Retrospective study of women who had a planned pregnancy at recruitment.Setting Joint Royal College of General Practitioners/Royal College of Obstetricians and Gynaecologists study based in general practice in England, Scotland and Wales, between 1976 and 1987.Subjects 1. Prospective study: Four hundred and thirty-three women with a recruitment unplanned pregnancy ending in induced abortion (abortion group) and 1035 women with a recruitment unplanned pregnancy which ended naturally (nonabortion group). All subsequently had a planned pregnancy, or were known to be trying to conceive at some point during the follow-up2. Retrospective study: Nine thousand two hundred and ninety-nine women who presented at recruitment with a planned pregnancy.Main outcome measure The women's estimated length of planning time, expressed as a fertility rate ratio.Results Induced abortion was not related to future fertility. In the prospective study, the fertility rate ratio (FRR) of the abortion group relative to the nonabortion group was 0.94 (95% CI0.83 to 1.07, P= 0.37). This result was supported by the retrospective study, which again showed no important difference between the two groups.Conclusion Induced abortion does not appear to have an important effect on future fertility.

Notes: Objective To quantify the changes in serum albumin during human pregnancy.Design Longitudinal prospective study.Setting Before conception and antenatal clinic.Subjects Sixty-nine normal women and 23 women with Type 1 diabetes.Interventions Administration of Evans' blue dye and collection of serum samples.Main outcome measures Albumin concentration, plasma volume and intravascular mass of albuminResults In normal subjects serum albumin concentration showed a significant decrease of 1.9 (95% CI 1.0 to 2.9) g/l by 7 weeks gestation with a further 8.2 (95% CI 7.5 to 8.9) g/l decrease by 36 weeks gestation, an overall change of 22%. Plasma volume first increased significantly by 190 (95% CI 105 to 275) ml between 7 and 12 weeks, with a further increase of 1003 (95% CI 871 to 1135) ml between 12 and 36 weeks of pregnancy, a change of 53%. The intravascular mass of albumin showed no change between non-pregnant, 7 and 12 week values but there was a significant rise of 19.5 (95% CI 15.1 to 23.9) g between 12 and 28 weeks of gestation, an overall increase of 19%. Diabetic subjects showed similar changes.Conclusions Rather than simply reflecting plasma volume dilution, the changes in serum albumin imply alterations in albumin metabolism during pregnancy.