Stress During Pregnancy May Increase Chance Of Having A Girl

What's the one thing that everyone always tells you to do during pregnancy? Relax, right? So much so that we all have probably gotten sick of hearing it at some point. And while it is totally one of those "easier said than done" type situations, according to a new study, the stress we carry around with us during pregnancy can impact much more than just our blood pressure.

Columbia University Irving Medical Center took a closer look at the link between stress and pregnancy, and their findings, published online in the journal PNAS, the Proceedings of the National Academy of Sciences, are pretty darn interesting.

This study specifically looked at markers of maternal stress -- both physical and psychological -- that may influence a baby's sex and the likelihood of preterm birth. Why? Because stress can manifest in many different ways, both as a subjective experience and in physical and lifestyle markers.

Study leader Catherine Monk, PhD, professor of medical psychology at Columbia University Vagelos College of Physicians and Surgeons and director of Women's Mental Health in the Department of Obstetrics & Gynecology at NewYork-Presbyterian/Columbia University Irving Medical Center and her team looked at 27 different indicators of psychosocial, physical, and lifestyle stress collected from questionnaires, diaries, and daily physical assessments of 187 otherwise healthy pregnant women, ages 18 to 45.

Of the women who took part in the study, about 17% (32) of the women were psychologically stressed, with clinically meaningful high levels of depression, anxiety, and perceived stress. Another 16% (30) were physically stressed, with relatively higher daily blood pressure and greater caloric intake compared with other healthy pregnant women. The majority (nearly 67%, or 125) were healthy.

Portrait of young woman covering her face with both hands in defeat and frustration
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She says, "The womb is an influential first home, as important as the one a child is raised in, if not more so."

And as strange as it may sound, the study also found that stress during pregnancy can possibly impact the sex of the bay you are carrying. The data showed that women experiencing physical and psychological stress are less likely to have a boy. On average, around 105 males are born for every 100 female births. But in this study, the sex ratio in the physically and psychologically stressed groups favored girls, with male-to-female ratios of 4:9 and 2:3, respectively.

Pretty interesting stuff. And this team actually isn't the first to make this correlation.

"Other researchers have seen this pattern after social upheavals, such as the 9/11 terrorist attacks in New York City, after which the relative number of male births decreased," says Monk. "This stress in women is likely of long-standing nature; studies have shown that males are more vulnerable to adverse prenatal environments, suggesting that highly stressed women may be less likely to give birth to a male due to the loss of prior male pregnancies, often without even knowing they were pregnant."

So then we are left with the questions of what can actually be done to help pregnant women manage their stress levels.

Monk suggests that social support and more screening during pregnancy will play the biggest roles, "screening for depression and anxiety are gradually becoming a routine part of prenatal practice," says Monk. "But while our study was small, the results suggest enhancing social support is potentially an effective target for clinical intervention."

READ NEXT: The Stress You Felt When You Got Pregnant Influences Your Kid's Stress Now

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