Maternal trait anxiety and prenatal social support predict pregnancy length and infant characteristics at birth during the pandemic threat

ABSTRACT

According to the theoretical prediction of the smoke detector principle, heightened anxiety as a personality trait could lead to better survival and reproductive success in unpredictable environments. Yet published studies suggest that maternal anxiety negatively affects gestation and birth outcomes, which may lead to decreased reproductive success. To resolve this conundrum, we studied the association between maternal anxiety and birth outcomes during the COVID-19 pandemic. Data collected from 1080 expectant mothers from the Corona Mums Project included maternal trait anxiety (STAI X2), perceived emotional support (PES), duration of gestation, and infant parameters at birth taken from hospital health records. After adjusting for covariates, multiple regression models showed that STAI X2 positively predicted infant birth weight (β=0.07, p=0.023) and length (β=0.08, p=0.010). PES positively predicted only birth weight (β=0.06, p=0.048). Neither of these factors was significantly related to duration of gestation, although the association with PES was of borderline significance (β=0.06, p=0.053). The results suggest that maternal increased ability to detect threats, indicated by her trait anxiety during the unpredictable conditions of COVID-19, was associated with better infant characteristics at birth. This may improve infant survival and maternal reproductive success, implying that increased trait anxiety could be adaptive during environmental threats.