Regression analyses for prenatal maternal anxiety and gestational age
We also examined the association between maternal anxiety and gestation (Table 2-B). In the full cohort, a stronger association was found for those reporting symptoms in the 30th week. Children exposed to maternal anxiety prenatally, across both the 17th and 30th gestational weeks, were at higher risk of short gestational age, compared to those not exposed and those exposed only once during pregnancy. This association was only moderately reduced, after adjusting for smoking and alcohol consumption and remained significant. Similarly to the associations for birthweight, these associations was further reduced, but remained robust after adjusting for multiple birth-related and socio-demographic variables in step 2 and 3.
In the sibling-design, we found no significant associations between maternal anxiety and gestational age. The confidence intervals were quite wide and overlapped the corresponding confidence intervals derived from the full cohort. Unlike the case of birthweight, the different set of adjustments did not change the magnitude of the associations.