Childhood adversity and time to pregnancy in a preconception cohort.

We examined the association between childhood adversity and fecundability (the per-cycle probability of conception), and the extent to which childhood social support modified this association. We used data from 6318 female participants aged 21-45 years in Pregnancy Study Online (PRESTO), a North American prospective preconception cohort study (2013-2022). Participants completed a baseline questionnaire, bimonthly follow-up questionnaires (until pregnancy or a censoring event), and a supplemental questionnaire on experiences across the life course including adverse childhood experiences (ACEs) and social support (using the modified Berkman-Syme Social Network Index [SNI]). We used proportional probabilities regression models to compute fecundability ratios (FRs) and 95% CIs, adjusting for potential confounders and precision variables. Adjusted FRs for ACE scores 1-3 and ≥4 vs 0 were 0.91 (95% CI, 0.85-0.97) and 0.84 (95% CI, 0.77-0.91), respectively. The FRs for ACE scores ≥4 vs 0 were 0.86 (95% CI, 0.78-0.94) among participants reporting high childhood social support (SNI ≥4) and 0.78 (95% CI, 0.56-1.07) among participants reporting low childhood social support (SNI <4). Our findings confirm results from 2 previous studies and indicate that high childhood social support slightly buffered the effects of childhood adversity on fecundability.