Newsweek, October 14, 2019

Stressed pregnant women are less likely to give birth to boys, according to researchers who investigated how a mother's health can affect their child. The study, published in the journal  PNAS , involved 187 pregnant women aged between 18 and 45, who filled out questionnaires and had physical assessments. Mirroring the findings of previous studies, stress levels appeared to affect the sex of the babies, the researchers found. The authors explained that in the general population, there are 105 males born for every 100 females. But in the women who were stressed, the ratios shifted to 4:9 for physically stressed mothers, and 2:3 for those under psychological stress. The more social support the women had the higher their chance of having male baby.