Parental Separation, Parental Alcoholism, and Timing of First Sexual Intercourse

Abstract

Purpose We examined timing of first voluntary sexual intercourse as a joint function of parental separation during childhood and parental history of alcoholism. Methods Data were drawn from a birth cohort of female like-sex twins (n=569 African Ancestry [AA], n=3415 European or other Ancestry [EA]). Cox proportional hazards regression was conducted predicting age at first sex from dummy variables coding for parental separation and parental alcoholism. Propensity score analysis was also employed comparing intact and separated families, stratified by predicted probability of separation. Results Earlier sex was reported by EA twins from separated and alcoholic families, compared to EA twins from intact nonalcoholic families, with effects most pronounced through age 14. Among AA twins, effects of parental separation and parental alcoholism were largely nonsignificant. Results of propensity score analyses confirmed unique risks from parental separation in EA families, where consistent effects of parental separation were observed across predicted probability of separation. For AA families there was poor matching on risk-factors presumed to predate separation, which limited interpretability of survival-analytic findings. Conclusions In European American families, parental separation during childhood is an important predictor of early-onset sex, beyond parental alcoholism and other correlated risk-factors. To characterize risk for African Americans associated with parental separation, additional research is needed where matching on confounders can be achieved.

Physical and neurobehavioral determinants of reproductive onset and success

“…Previous studies have invariably focused on only the socio-cultural determinants of AFS and the relevance of early AFS to poor educational achievement and other adverse outcomes12,13. We recognise the importance of diverse socio-cultural factors, which are reflected by the discordant changes in AFS and AFB seen by year of birth in the UK Biobank study (Figure S4).…”

“…In particular, parental and peer norms and behaviours have a strong influence on teenagers’ sexual behaviour14–16. Twin studies have suggested some genetic contribution to AFS17,18, however observations of older AFS among monozygous compared to dizygous twins13 casts doubt on the validity of twins studies to accurately estimate the heritability of this trait.…”

The Association of Low Parental Monitoring With Early Substance Use in European American and African American Adolescent Girls

“…First, logistic regression analyses were used to examine the association between low parental monitoring and early substance use without and with covariate adjustment. Next, consistent with earlier work (e.g., Waldron et al, 2014Waldron et al, , 2015, PSA was conducted to compare adolescents who reported low parental monitoring (lowest 25% within racial/ethnic group) and those who reported higher parental monitoring (upper 75%) based on their predicted probability of experiencing low parental monitoring. PSA is a statistical technique that can be used to reduce bias from confounding variables by matching groups on a range of highly correlated risk factors presumed to predate exposure (Green & Stuart, 2014;Rosenbaum, 2010;Rosenbaum & Rubin, 1983;West et al, 2014), in this case, to low parental monitoring.…”

The effects of age at menarche and first sexual intercourse on reproductive and behavioural outcomes: a Mendelian randomization study

“…Indeed, adverse childhood experiences have been shown to associate with earlier age at menarche, the start of a woman's sexual maturity and reproductive potential (5). Age at first sexual intercourse is also related to the childhood environment (6)(7)(8). Whilst adopting a fast life history strategy may increase fitness, it may also have costs to the individual such as those associated with teenage pregnancy and risky behaviours such as violence, criminality, and substance abuse (3,9,10)).…”