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Notes: Objective To investigate maternal and fetal folate and vitamin B12 concentrations in pregnancies affected by neural tube defects (NTD).Design Measurement of folate and vitamin B12 concentrations in amniotic fluid, fetal blood and maternal blood samples in midgestation.Subjects 32 women undergoing termination of pregnancy at 14–21 weeks gestation for social reasons (n = 24) or for fetuses with neural tube defects(n = 8).Interventions Fetoscopy before intra-amniotic injection of prostaglandins.Results In normal pregnancies there was a positive correlation between maternal and fetal serum folate, and the fetal serum and red blood cell folate concentrations were higher than the maternal. There were no differences in amniotic fluid, maternal blood or fetal blood folate concentrations between pregnancies with NTD and normal pregnancies. Although amniotic fluid vitamin B12 was lower in pregnancies with NTD, maternal serum vitamin B12 concentration was not reduced.Conclusion In this small group of pregnancies with NTD at mid-gestation there is no evidence to suggest folate or vitamin B12 deficiency.

Notes: Objective To determine the value of early pregnancy sonography in detecting fetal abnormalities in an unselected obstetric population.Design Prospective cross-sectional study. All women initially underwent transabdominal sonography and when the anatomical survey was considered to be incomplete, transvaginal sonography was also performed (20.1 %). Nuchal translucency was measured and karyotyping was performed as appropriate.Setting University Department of Obstetrics and Gynaecology.Participants 6634 sequential unselected women (mean maternal age 29–9 years, range 13–50; mean gestational age 12+4 weeks, range 11+0-14+6), carrying 6443 live fetuses participated in this study.Main outcome measure Detection rate of fetal anomalies and the associated cost per case detected in early pregnancy.Results The incidence of anomalous fetuses was 1.4% (926443) including 43 chromosomal abnormalities. The detection rate for structural abnormalities was 59.0% (37/63, 95% CI 46.5–72.4) and the specificity was 99.9% in early pregnancy. When the first and second trimester scans were combined, the detection for structural abnormalities was 8 1.0% (5 1/63, 95% CI 67.7–89.2). Seventy-eight percent (31/40) of chromosomal abnormalities (excluding three cases of XXY) were diagnosed at 11–14 weeks, either because of a nuchal translucency greater than or equal to the 99th centile for gestational age (43%; 17/40,95% CI 27-4–60.4), or due to the presence of structural abnormalities (35%; 14/40, 95% CI 21.2–52.8). Sixty-five percent (15/23) of cases of trisomy 21 were also diagnosed either because of having a nuchal translucency greater than or equal to the 99th centile (57.0%; 13/23) or due to the presence of a structural abnormality (9.0%; 2/23). Overall, the detection rate of structurally abnormal fetuses was 59% (37/63) in early pregnancy and 81% in combination with the second trimester scan. The cost per abnormality diagnosed in early pregnancy is estimated to be f6258 per structurally abnormal fetus, £7470 per chromosomal abnormality and f4453 per anomalous fetus.Conclusion The majority of fetal structural and chromosomal abnormalities can be detected by sonographic screening at 11–14 weeks, but the second trimester scan should not be abandoned.

Notes: Objective To review the obstetric problems, pregnancy outcome and management of carriers of haemophilia.Design Retrospective review of haemophilia and maternity unit records.Setting Haemophilia Comprehensive Care Centre.Participants Thirty-two carriers of haemophilia (24 haemophilia A, eight haemophilia B) who had their obstetric care at the Royal Free Hospital over a 10-year period (1985–1995).Main outcome measures Uptake and results of prenatal diagnosis, changes in factor levels during pregnancy, effect of knowledge of fetal gender on obstetric management and neonatal outcome, and maternal haemorrhagic complications.Results There were 82 pregnancies and 32 resulted in miscarriage or social abortion. The option of prenatal diagnosis was taken up in only 35% (17/48) of pregnancies. There were five affected male fetuses diagnosed prenatally but only three women opted for termination of the pregnancy. Knowledge of fetal gender was unavailable to the attending obstetrician in 46% (21/46) of pregnancies. A fetal scalp electrode was applied in eight, fetal blood sampling was performed in four, and ventouse delivery was conducted in one of these pregnancies. No adverse effects were reported from the first two procedures, but the ventouse delivery was associated with a huge cephalhaematoma requiring blood transfusion. On the other hand, in five cases fetal blood sampling was withheld because fetal gender was unknown. Four of the eight caesarean sections performed might have been avoided if the gender had been known. The incidence of primary and secondary postpartum haemorrhage was high, 22% (including two cases with massive haemorrhage) and 11%, respectively.Conclusion Carriers of haemophilia A and B require special obstetric care with close liaison with the haemophilia centre, and management guidelines should be available and observed. Knowledge of fetal gender is very valuable for management in labour and should be determined antenatally even if the mother declines prenatal diagnosis.

Notes: Objective To determine the influence of the position of the fetal neck on nuchal translucency measurement.Design A prospective cross-sectional study.Population One hundred and ninety-six.Methods Nuchal translucency was measured in the mid-sagittal plane, with the fetal neck in the flexed, neutral and extended positions. Measurements were made to the nearest 0.1 mm. Statistical analysis used the paired t-test for differences between the extended and neutral positions, [A extended nuchal translucency] and the flexed and neutral positions [A flexed nuchal translucency].Results The mean extended nuchal translucency was 0.62 mm greater than the mean neutral nuchal translucency value [95% confidence interval 0.53 to 0.70, T= 14.33, P〈inlineGraphic alt="leqslant R: less-than-or-eq, slant" extraInfo="nonStandardEntity" href="urn:x-wiley:14700328:BJO872:les" location="les.gif"/〉 0.000011. The mean flexed nuchal translucency was 0.40 mm less than the mean neutral nuchal translucency value [95% CI 0.34 to 0.47, T = 11.99; P= 〈 0.000011. The repeatability coefficient was lower in the case of neutral nuchal translucency measurements [0.48] and was higher in the other groups [extended = 1.04, flexed = 0.701.Conclusion Fetal neck position can make a significant difference to nuchal translucency measurements. Repeatability of measurements are more accurate with the fetal neck in the neutral position. These findings have important implications for clinicians using nuchal translucency to screen the general obstetric population.

Notes: Summary. To assess DDAVP (1-deamino-8-d-arginine vasopressin; desmopressin) nasal spray in the management of menorrhagia in patients with inherited bleeding disorders, 39 women (aged 18–50 years) with menorrhagia were recruited and were randomized to start 2 months' therapy with placebo or DDAVP (300 µg) spray in a double-blind crossover study. Twenty-eight and 24 completed first and second period of treatment, respectively. Menstrual loss was assessed using the pictorial blood assessment chart (PBAC) during each treatment period. The main outcome measure was comparison of PBAC scores following DDAVP and placebo treatments. The safety of DDAVP spray was also assessed by monitoring side-effects. Overall, PBAC scores were significantly lower in the second treatment period than the first (P = 0.01). After adjusting for this differences, mean PBAC scores were slightly lower (mean difference 8; 95% confidence interval of − 15.5 to 31.6) in women receiving DDAVP than when receiving placebo, although this difference was not statistically significant (P = 0.51). In conclusion, although there was an indication that menstrual bleeding was less heavy when women received DDAVP than when receiving placebo, the small sample size meant that this difference was not significant.