ABSTRACT. A specific, enzyme-linked immunoabsorbent assay was used to determine the concentration of the 35,000 mol wt surfactant apoprotein (SP-A) in samples of amniotic fluid obtained from nondiabetic (n = 358) and diabetic (n = 29) women. The enzyme-linked immunoabsorbent assay was performed with rabbit antibodies directed against SP-A present in lavage fluid from a patient with alveolar proteinosis. Amniotic fluid SP-A concentrations increased as a function of gestational age, from <3 jtg/ml at 30-31 wk to 24 pg/ml at 40-41 wk, and were positively correlated with the lecithin to sphingomyelin ratio ( p < 0.01). SP-A concentrations also increased as a function of gestational age in shake test positive samples ( p < 0.05), but were unchanged in shake test-negative samples. There was no difference in the surfactant apoprotein concentration of male compared with female fetuses at any gestational age. In amniotic fluid obtained from 20 diabetic women, SP-A levels were significantly less than in nondiabetic pregnancies that were matched for gestational age and sex of the fetus ( p < 0.05). The SP-A concentrations in amniotic fluids obtained from nine women who were diabetic and hypertensive and from 10 hypertensive women were not different from matched controls. The relationships described above were valid whether the SP-A concentration was expressed per mg protein or per ml amniotic fluid. These data are suggestive that the concentration of amniotic fluid SP-A is decreased in diabetic pregnancies. (Pediafr Res 24: 728-734, 1988)

After induced ovulation and insemination on day 1, followed by ovariectomy on day 2, a schedule of 1 mg of progesterone in two injections in oil per day on days 2-4 inclusive followed by 2 or 3 mg per day on days 5-9 inclusive was found to induce implantation in the majority of ovariectomized rabbits. Implantation percentages (102 x total no. of implants on day 10 -;-no. of corpora lutea) in different groups of 8-11 rabbits varied between 24 and 61 %; sham-operated and vehicle-injected controls gave overall significantly higher percentages of 57-79%. The addition of 0·1--0·5 p-g of 3,17f3-oestradiol to experimental groups at various times during these procedures resulted in implantation percentages of 49-63 %, but did not consistently improve them.The only seemingly consistent effect of oestrogen was on implantation maintenance from day 10 onwards in does with surviving foetuses. These showed 5·1 implants/doe on day 10 and 2·8 foetuses/ doe on day 30 with progesterone alone, and 5·2 implants/doe on day 10 and 3·7 foetuses/doe on day 30 (a significant difference) with added oestradiol, as against 6·0 implants/doe and 3·8 foetuses/doe on days 10 and 30 respectively in control animals.Since the adrenal glands may contribute sufficient steroids, particularly oestrogens, to affect conclusions, rabbits both ovariectomized and adrenalectomized were subjected to similar tests in comparison with sham-operated controls. No effects of adrenalectomy or of added oestrogen were apparent, and the results were otherwise similar to those above.Overall, these findings demonstrate difficulties in producing consistent results and go far towards explaining the contradictory literature that has grown up on this subject.