• Posted November 6, 2024

PCOS Plus Obesity Can Be Hazardous in Pregnancy

Women who are pregnant but who also have the ovarian cyst disorder polycystic ovary syndrome (PCOS) are at higher odds of giving birth to an underweight baby, new Norwegian research shows.

The risk rises even higher if the woman with PCOS is also obese, the study found.

“In women of normal weight who have PCOS, we only find that their children have a lower birth weight compared to women who do not have PCOS," noted study lead author Dr. Eszter Vanky.

"It is the group of children born to mothers with obesity that stands out the most," she added. "These babies have lower weight, shorter stature and a smaller head circumference. Obesity places an additional burden on mothers who have PCOS and their children."

Vanky is professor of clinical and molecular medicine at the Norwegian University of Science and Technology in Trondheim.

PCOS is a common gynecologic disorder, affecting about 1 in every 8 women. It's a hormonal condition that's characterized by elevated levels of male hormones that can cause infrequent or irregular menstrual periods and the growth of small cysts on the ovaries.

The new study looked at data on more than 70,000 children, 390 of who were born to women diagnosed with PCOS.

Babies born to women with PCOS tended to have smaller birth weights, were shorter and had a smaller head circumference, compared to women born to women without the disorder.

However, the differences in newborn sizes was most pronounced if the mom with PCOS was also obese, Vanky's group said.

One issue is that obesity and PCOS often occur together, the researchers noted.

The findings were somewhat surprising, Vanky said, because "women who are generally overweight and gain a lot of weight during pregnancy usually have an increased risk of giving birth to large babies."

"This also applies to women who develop gestational diabetes," she added in a university news release. "On average, women with PCOS have higher BMIs, gain more weight during pregnancy and 25 percent of them develop gestational diabetes. However, the outcome is the opposite: these women give birth to babies who are smaller than average."

"We still don’t know why, but we see that the placenta is affected in these women," Vanky said. As she explained, "the placenta delivers nutrients to the baby through the umbilical cord. In women with PCOS, we see that the placenta is generally smaller in size. At the same time, it must provide everything the baby needs, so it has to work very hard to meet these demands. Sometimes, however, the placenta can’t keep up, which can lead to placental insufficiency and, in rare cases, fetal death.”

How PCOS might be affecting the health of the placenta is not yet known, according to the researchers.

As to the longer term effects of PCOS during pregnancy on a child's health, the Norwegian team noted that they have gathered data on some affected children up to the age of 7.

“We saw that the children born to mothers with PCOS generally had more central obesity, meaning they were larger around the waist,” Vanky said. “They bear small signs that their mother has PCOS. It may therefore be an advantage to know about this so we can provide guidance on lifestyle and diet."

The study was published recently in the journal JAMA Network Open.

More information

Find out more about PCOS at the Mayo Clinic.

SOURCE: Norwegian University of Science and Technology, news release, Nov. 5, 2024