A Stressful Pregnancy Reduces The Chance Of Having A Boy

A Stressful Pregnancy Reduces The Chance Of Having A Boy

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Enduring physical or mental stress during pregnancy means you’re less likely to have a boy

Pregnancies that include physical or mental stress may have a huge impact on the sex of the baby, according to a new study. Pregnant people who undergo physical or mental stress during their pregnancies are less likely to have a boy. They may also have a higher risk of preterm birth.

“The womb is an influential first home,” says the lead author of the study Catherine Monk, director of women’s mental health in OB/GYN at NewYork-Presbyterian/Columbia University Irving Medical Center. “We do know that males are more vulnerable in utero, and presumably the stress in these women is of a long-standing nature.”

There are an average of 105 boys born for every 100 female births in nature. But in this study, women who had higher blood pressure and other signs of physical stress had four boys for every nine girls, while moms who were psychologically stressed had two boys for every three girls. All of the women in the study had healthy pregnancies.

Interestingly, this particular birth pattern has presented itself before — both in times of national crisis. “Other researchers have seen this pattern of a decrease in male births related to traumatic cataclysmic events,” Monk says. “One of them being President Kennedy’s assassination and the other being the September 11 terrorist attacks in New York City.”

Those who were stressed out during their pregnancies were also more likely to give birth prematurely compared to those who were not stressed. However, pregnant people with more mental stress also had more birth complications, such as longer labor, than those with physical stress.