Longitudinal associations between prenatal testosterone and postpartum outcomes in a sample of first-time expectant lesbian couples.

Although increasing numbers of gay and lesbian individuals ultimately become parents, the vast majority of research on the transition to parenthood focuses exclusively on heterosexual samples. Even less is known about the physiological implications of this major life transition among those who identify as sexual minorities. The present study begins to redress these gaps in the literature by assessing prospective links between prenatal testosterone, a steroid hormone that is negatively associated with nurturance and caregiving, and postpartum outcomes in a sample of 25 first-time expectant lesbian couples (N = 50 individuals). Consistent with prior work in heterosexual samples, which suggests that lower testosterone promotes both partnering and parenting, we found that, in both partners, lower testosterone during the prenatal period predicted better romantic relationship and parenting outcomes at three-months postpartum (e.g., higher relationship quality, more time spent doing baby care). There was also evidence for dyadic associations; for instance, birth mothers reported more overprotective behavior, and non-birth mothers reported greater commitment, when their female partners had lower testosterone. Together, our findings contribute important new knowledge about the functionality of testosterone in close relationships contexts, including some of the first evidence among sexual minorities.