The cervical factor in patients with ovulatory infertility.

Thirty patients with ovulatory infertility had two consecutive postcoital tests. Couples with inconclusive or abnormal results had in vitro sperm penetration tests, using donor mucus and donor sperm. The quality of the cervical mucus, the concentration of plasma oestradiol and luteinising hormone and the result of the post-coital test were assessed each day. After two consecutive cycles, the postcoital test was normal in 84 per cent, inconclusive in 12 per cent and abnormal in 4 per cent of the women. The in vitro cross reaction test showed that two couples had definite abnormality in the sperm-cervical mucus interaction and one couple were having inadequate coitus. Normal post coital tests should not be expected with an Insler cervical mucus score of less than 8. Normal postcoital tests were found between days -2 and +1 with respect to the luteinising hormone peak. There is a direct relation between the plasma oestradiol concentration and the individual cervical score but the predictability of plasma oestradiol values for a given cervical score is very poor. The plasma oestradiol concentration was significantly different between groups having cervical scores less than 7 and 8-10 or 11-12 (p less than 0.01).