Surprise ‘Ozempic babies’ underscore links between obesity and fertility
June 25, 2024
Significant weight loss. Reductions in heart, kidney, and nonalcoholic fatty liver disease. These are just a few of the unexpected benefits of a class of medications called glucagon-like peptide-1 receptor agonists (GLP-1 RAs) that were originally designed to treat diabetes.
Now, we can add improved fertility to the list of surprise effects related to GLP-1 RAs, better known by the brand names Ozempic, Wegovy, Mounjaro, and Zepbound.
All around the U.S., women who have struggled for years with low fertility or infertility are expecting “Ozempic babies” after taking GLP-1 RAs to treat obesity or diabetes, according to reports on CNN and USA Today. Many women are sharing their experiences on social media, using hashtags like #OzempicBaby to connect. We have seen an increase in these scenarios at UT Southwestern’s Ob/Gyn and Weight Wellness clinics, too.
GLP-1 RAs, which have been approved by the U.S. Food and Drug Administration (FDA) to treat diabetes and obesity, have helped patients lose an average of 15%-20% of their total body weight in clinical trials. For patients with obesity, significant weight loss can result in restored ovulation, more regular periods, and rebalanced estrogen, a hormone that rises with obesity and can diminish fertility.
All these changes can lead to unexpected pregnancy, which for some patients is a welcome surprise. But amid their joy, many women are asking the same question: Are these medications safe for me and my baby?
There is limited data about exactly how GLP-1 RAs affect fertility, pregnancy, and breastfeeding. But as the popularity of these blockbuster medications grows – 1 in 8 adults have taken a GLP-1 RA, according to a recent poll – so will the research.
For now, let’s look at some of the mechanisms that we know cause weight-loss drugs to improve fertility among women and men.
Why do GLP-1 RAs potentially improve fertility?
The short answer is, it’s complicated.
GLP-1 RAs were originally designed to treat diabetes by mimicking a hormone response in the pancreas that stimulates the body to produce more insulin after a rise in blood sugar levels, usually triggered by eating. This hormonal process makes the stomach empty slower and signals the brain that the body feels full – reducing appetite and cravings, and over time leading to weight loss.
Diabetes interferes with ovulation and can cause irregular periods. Type 2 diabetes is common in patients with obesity, and obesity increases production of estrogen hormones to abnormal levels, causing further fluctuation in periods and ovulation along with an increased risk of pregnancy complications and miscarriage.
Estrogen disruption is also associated with polycystic ovary syndrome (PCOS), a hormonal imbalance characterized by overweight/obesity, infertility, elevated testosterone levels, insulin resistance, ovarian cysts, facial hair overgrowth, and thinning hair on the scalp in women. About 7%-10% of women of reproductive age in the U.S. have PCOS.
Here’s where the GLP-1 RAs come in. When women with obesity lose about 10% of their body weight, symptoms such as irregular periods and imbalanced estrogen may improve.
In what’s known as the SELECT trial, co-authored by UT Southwestern endocrinologist Ildiko Lingvay, M.D., M.P.H., M.S.C.S., 44% of patients using semaglutide lost more than 10% of their body weight within two years, and 11% of patients lost more than 20% – more than enough to improve fertility.
A few studies also suggest that GLP-1 RAs may increase fertility in men, particularly those with obesity, by improving semen concentration, motility, and morphology. So, patients who are taking these medications for weight loss or diabetes should talk with their doctor about current fertility, future plans, and the possibility of a “surprise” pregnancy.
Are GLP-1 RAs safe during pregnancy?
Women who have struggled with fertility may not consistently use birth control, and those who have had irregular periods for a long time might not notice missed periods due to pregnancy. Even women with regular periods may not know that they’re pregnant until six weeks’ gestation or beyond.
So, it’s quite possible for a pregnancy to be exposed to GLP-1 RA medication for weeks or even months before the pregnancy is detected.
More research is needed to understand whether anti-obesity medications such as semaglutide (Ozempic, Wegovy) and tirzepatide (Mounjaro, Zepbound) interfere with birth control and whether they are safe during pregnancy. However, science has historically excluded pregnant women from clinical studies. As UT Southwestern’s Chief and Professor of Obstetrics and Gynecology, Catherine Spong, M.D., noted in Vox, that excluding pregnant patients from GLP-1 RA research over safety concerns is to “provide care without adequate evidence.”
A 2023 observational study involving 50,000 pregnant women with Type 2 diabetes found no statistically significant differences in the number of major congenital malformations among the more than 900 women who were taking GLP-1 RAs when they learned they were pregnant. Novo Nordisk, the manufacturer of Ozempic and Wegovy, is building a registry of women who took Wegovy while pregnant or nursing to track health data through pregnancy and the first year after delivery. So is Eli Lilly, maker of Mounjaro and Zepbound.
In the absence of definitive data, the current FDA recommendation is to stop the medicine two months before pregnancy when possible because the medication can remain in your system for some time. In animal studies, use of the medication was associated with lower birth weights; it’s unclear whether this was due to the medication itself or maternal weight loss during the pregnancy, which is generally not advised. It is also recommended to stop taking GLP-1 RA medication while breastfeeding because the drug can enter the breast milk.
Patients who had irregular periods and weight fluctuations before taking GLP-1 RAs might not notice right away when they become pregnant. UT Southwestern recommends that patients with obesity work with an obesity specialist along with their Ob/Gyn before, during, and after pregnancy to reduce potential risks and increase the chances for a healthy pregnancy.
Optimizing your health before and during pregnancy
Women with obesity also face an increased risk of pregnancy complications, including preeclampsia, C-section delivery, and pregnancy loss. While some weight gain is normal during pregnancy, patients with obesity should work with their health care provider to manage their weight gain during this time.
At UT Southwestern, Ob/Gyns, maternal-fetal medicine doctors, endocrinologists, and obesity specialists in the Weight Wellness Program can help you understand what body composition is healthy for you, treat underlying emotional and physical factors associated with subfertility and obesity, and explore weight management options such as lifestyle changes, bariatric surgery, and medication that is approved for use during pregnancy.
It’s natural to be curious about the potential benefits of GLP-1 RA medications for weight loss, cardiovascular disease, and diabetes, particularly as they continue to get more attention in the news and on social media. Please don’t hesitate to talk with your health care provider about GLP-1 RAs and their possible effects on fertility. Bring it up with your doctor if they don’t mention it first because being aware of the possibility of pregnancy can help you make the best decision for your health and your future.
To talk with a specialist about weight wellness, diabetes management, or fertility, call 214-645-8300 or request an appointment online.