Evaluation of factors predicting natural conception within one year of trying after ceasing contraception

Abstract

Objectives: This study aimed at investigating the value of various clinical factors of the female and male on prediction of pregnancy. We hypothesized that age, body mass index and stress level of the couple, serum anti-Mullerian hormone (AMH) level of the female, as well as total motile normal-morphology count (TMNC) in semen samples, were potential factors that predict occurrence of pregnancy within one year of trying and time-to-pregnancy. Methods: This was a prospective cohort study on 112 couples attending a community family planning clinic for preconceptional health check. These couples were planning to cease their contraception in preparation for conception. Their basic demographic and clinical parameters were recorded. The female had a blood test for serum AMH, and the male had a semen analysis according to the World Health Organisation manual (5thedition). Stress level was measured by the Perceived Stress Scale (PSS). Parameters were compared between those who conceived and not at one year after ceasing contraception by Mann-Whitney U test, and those significant parameters were entered into a standard binary logistic regression model to study their independent predictive value on occurrence of pregnancy. Among those who got pregnant within one year, correlation between time-to-pregnancy and clinical parameters of the couple were studied by Spearman’s correlation. Results: Of the 112 couples recruited, 100 completed follow-up and were available for analysis. Two of them were using hormonal contraception, one using intrauterine device whereas the rest were using barrier or natural contraception. Within one year after ceasing contraception, 61 (61%) couples got pregnant, and they demonstrated significantly younger age (p=0.008) and higher serum AMH level (p=0.038) of the woman, as well as higher TMNC in semen of the man (p=0.015) compared with those not conceiving, but there were no differences in age of the man and PSS score of the couple. Among those conceived within one year, none of the clinical parameters were significantly correlated with time-to-pregnancy (p>0.05). In the logistic regression model, only age of the woman (OR 1.154, p=0.032) and TNMC of the man (OR 0.918, p=0.047), but not serum AMH level of the woman, were independent predictors of pregnancy within one year. Conclusions: Age of the woman and semen parameter of the man, but not serum AMH level of the woman, are significant independent predictors of pregnancy after trying for one year.