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Notes: Sixty-nine patients who presented with threatened abortion had a number of investigations aimed at providing information with which to predict pregnancy outcome. Ultrasound examination, and measurement of plasma oestradiol and progesterone levels were all significantly more accurate in predicting the pregnancy outcome than clinical examination. Measurements of plasma levels of β1-glycoprotein, alpha fetoprotein (AFP), beta subunit human chorionic gonadotrophin (hCG), cystyl aminopeptidase, and human placental lactogen (hPL) also appeared better than clinical examination but the differences did not reach statistical significance while measurement of hCG levels in early morning urine were less accurate than clinical examination.

Notes: Twelve anovulatory patients with normal serum prolactin values and six with elevated values were treated with bromocriptine and the effects on serum prolactin, FSH and LH levels were recorded. Ovulation resulted in one patient who had normal prolactin values and in all six who had raised values. No patient with normal basal prolactin values showed an increase in serum FSH during therapy with bromocriptine, whereas 5 of the 6 patients with elevated values showed significant increases. Similar results were obtained for LH. Although these differences were highly significant (P〈0·005) the majority of the serum FSH and LH values remained within the normal ranges. Five patients with normal basal prolactin values and one with elevated values were also treated with human pituitary gonadotrophin (HPG). An increase in ovarian responsiveness to HPG during therapy with bromocriptine was recorded in the one patient with initially elevated prolactin values. It was concluded that bromocriptine acts by allowing FSH to rise above threshold requirements for follicular stimulation.

Notes: Sixteen women provided saliva samples throughout a menstrual cycle and the concentration of oestradiol was measured. Blood samples were taken around mid-cycle and the luteinizing hormone peak was used to diagnose the timing of ovulation. The levels of oestradiol in saliva followed the same pattern as in blood. The peak of oestradiol in saliva could be used to predict accurately the time of onset of the next menstrual period. The analysis of saliva could be useful in the investigation of women in whom serial venepunctures are not possible.

Notes: Urinary oestrogen and pregnanediol excretion was measured daily (“daily monitoring”) for a complete cycle in 20 normally menstruating women, in one patient with an anovulatory cycle and for 28 days in a patient with secondary amenorrhoea. The measurements were also performed on urine specimens collected at weekly intervals for 4 to 6 weeks (“weekly tracking”) from 506 patients with evidence of abnormal ovarian function. These included 9 patients with primary amenorrhoea, 132 patients with secondary amenorrhoea, 138 patients with oligomenorrhoea and 227 patients with evidence of ovarian dysfunction and cycle lengths of 25 to 42 days. The results were subjected to statistical analysis. In the normal cycles, ovulation could be identified on the criteria of a rising pregnanediol value reaching or exceeding 2.0 mg. per 24 hours for a period of 7 days or more. Valid conclusions on the overall mean oestrogen and pregnanediol values for a complete cycle could be made from the results of weekly tracking, irrespective of which day the tracking commenced. Correlations were obtained by comparing the mean and maximum urinary oestrogen values and the variability of the values with the evidence of ovarian function indicated by the clinical classifications of the patients, the duration of the disorders and the subsequent occurrence of uterine bleeding. Mean oestrogen values of 10μ g. per 24 hours or less were associated with lack of ovarian function. For values higher than this a discriminant function based on both the mean oestrogen value and the variability of the oestrogen values was useful in predicting onset of spontaneous menstruation. A single urine specimen collected 4 to 8 days before onset of menstruation showing a raised pregnanediol value of 2.0mg. per 24 hours or more provided a valid test for ovulation in women with regular cycles, and a single urine specimen giving an oestrogen value of 10 pg. per 24 hours or less gave a valid indication of absent ovarian function in women with amenorrhoea for two years or more. In all other circumstances serial sampling at weekly intervals provided a valid assessment of ovarian activity. Application of these principles allows the greatest amount of information on ovarian function to be obtained with the greatest economy of effort.

Notes: Summary. Urine and plasma oestriol, plasma progesterone, human placental lactogen, α-glycoprotein and serum cystyl aminopeptidase were measured at intervals during 608 pregnancies. The predictive accuracy of low values for identification of pregnancies with low birthweight outcomes was assessed for each test at various gestations. Data were analysed to obtain 10th–90th centile values for each test from 28 weeks to delivery.Groups with values under different centile levels were compared: those under the lower centiles had higher proportions but smaller absolute numbers of low birthweight infants than those under higher centiles. No test was superior to the others at all centiles and gestations. Biochemical screening of pregnant populations to identify high-risk groups for intensive fetal monitoring has limited potential. If screening is used, the definition of high-risk groups is best achieved by practical rather than statistical criteria. If monitoring facilities are available and well accepted by patients then higher centile‘cut-offs’to define fetal risk may be used than when they are not. Combining any pair of tests with values below the 10th centile did not reduce false positive and negative predictions any more than could be achieved by movement of centiles up or down for a single test.

Notes: Basal serum levels of prolactin were measured in 37 infertile anovulatory patients who had failed to conceive on therapy with clomiphene citrate. Twenty of these patients, 16 of whom had galactorrhoea, had elevated basal serum prolactin values which were suppressed to normal or subnormal values during therapy with bromocriptine, the most commonly effective dose being 2·5 mg twice daily. Ovulation, as assessed by urinary oestrogen and pregnanediol measurements, was induced in 17 of these patients with pregnancy in 14. Ovarian responses short of defined criteria for ovulation were induced initially in eight patients, but these progressed to full ovulatory responses in five patients, either on the same or increased doses of bromocriptine. In all the patients who ovulated, the prolactin levels had been reduced below the mean value for normal women (10·6 ng-ml). The three patients who failed to ovulate all had values higher than this at a dose of bromocriptine reaching 5·0 mg thrice daily. There seemed to be no value in increasing the dose of bromocriptine once ovulation had been achieved. Of the 17 patients with normal basal prolactin values, only one had an unequivocal response to bromocriptine with ovulation and conception, even though the prolactin values in the majority were suppressed to below normal.

Notes: A case report of intrahepatic cholestasis of infancy presenting with chronic severe pruritus is described. This presentation is compared with similar cases attending this unit. Intrahepatic cholestasis of infancy and the pathogenesis of puritus associated with cholestasis are briefly discussed.

Notes: SUMMARY. The ecology of the phytoplankton of Heywood Lake, Signy Island, South Orkney Islands, Antarctica was investigated during 1969–72. The lake, which is ice-covered for 8–10 months per year, is moderately eutrophic due to enrichment by seal excreta.The annual cycle of the phytoplankton is described. During the winter (approximately May-September), very few algal cells could be detected in the water column and 14C fixation was below measurable limits. In spring (October-November), a rapidly-growing population of algae caused a large increase in the chlorophyll-a concentration (maximum value 170 mg m−2) but carbon fixation remained low, with values 〈500 mg C m−2 day−1. The algae contributing to this peak were mainly small chlorophytes and chrysophytes. The summer open-water period (December-March) was characterized by a different phytoplankton population dominated by cryptophytes. Chlorophyll levels were lower (c. 40 mg m−2) but 14C fixation rates 〉3 g C m−2 day−1 were measured on bright days. Values for Assimilation Number were very high (maximum value 10.5 mg C h−1 mg−1 (chlorophyll-a) in January (1971) though temperatures never exceeded 8°C. In autumn, the phytoplankton regressed to winter levels. Both spring and summer algal populations probably overwinter as resting stages.