TUESDAY, Feb. 14, 2017 (HealthDay News) -- A baby's gender might affect a pregnant woman's immune system, a new study suggests.
For the study, researchers checked levels of immune markers called cytokines in the blood of 80 pregnant women.
The researchers found no differences in cytokine levels based on fetal sex. But they did find that "the immune cells of women carrying female fetuses produced more pro-inflammatory cytokines when exposed to bacteria," said principal investigator Amanda Mitchell.
"This means that women carrying female fetuses exhibited a heightened inflammatory response when their immune system was challenged, compared to women carrying male fetuses," she explained.
Mitchell is a postdoctoral researcher at Ohio State University's Institute for Behavioral Medicine Research.
The researchers explained that inflammation is critical in the body's response to viruses, bacteria and chronic illnesses. But excessive inflammation stresses the body and can result in achiness and other symptoms.
Higher levels of inflammation among women carrying female fetuses could help explain why they tend to have worse symptoms of some conditions -- including asthma -- than women carrying male fetuses, the researchers said.
"This research helps women and their obstetricians recognize that fetal sex is one factor that may impact how a woman's body responds to everyday immune challenges and can lead to further research into how differences in immune function may affect how a women responds to different viruses, infections or chronic health conditions [such as asthma], including whether these responses affect the health of the fetus," Mitchell said in a university news release.
The study appears in the February issue of the journal Brain, Behavior and Immunity.
The U.S. National Institute of Child Health and Human Development has more on pregnancy.