Accuracy of men's recall of their partner's time to pregnancy

Background: Occupational studies of fertility often rely on men's report of time to pregnancy (TTP). We assessed accuracy of men's report of TTP compared with TTP derived from data from their female partners. Methods: Men from the Dieckmann diethylstilbestrol cohort were interviewed to assess fertility. Men were asked TTP for their most recent pregnancies. Their female partner was subsequently interviewed separately; TTP derived from her data was used as the gold standard. Our analysis was based on 202 couples. Results: Men's report was identical to the women's-derived TTP in 32% of couples; 74% differed by no more than 2 cycles. Men tended to underestimate TTP (mean difference = -1.2 cycles). Weighted kappa was 0.5 overall and varied by the man's education, the number of pregnancies he had fathered, his stated confidence in reporting, his exposure to diethylstilbestrol, pregnancy planning, and whether he was still married to the index partner. Conclusions: Overall accuracy of men's report of TTP was reasonably good, particularly for men who had fathered only one pregnancy.