DeutschPregnancy brings about a wide range of changes, influencing nearly every facet of life. People who are expecting often become more mindful than ever about what they consume, especially when it comes to medications. While drugs are a fundamental aspect of healthcare, their significance increases dramatically during pregnancy.
The CDC reports that the vast majority of pregnant individuals—nine out of ten—take some form of medication while pregnant. Yet, because clinical trials typically exclude pregnant participants due to ethical concerns, we often lack concrete data about how certain medications might impact pregnancy, particularly weight loss treatments. One of the more talked-about drugs, semaglutide (marketed as Ozempic), hasn’t undergone safety testing in pregnant individuals, leading to widespread speculation and unexpected pregnancies referred to as “Ozempic babies.” There is ongoing debate around what’s causing these surprises and what potential pregnancy-related risks we still don’t fully understand.
When addressing obesity in pregnant patients, healthcare professionals must weigh the dangers of obesity itself against any benefits or drawbacks that weight loss drugs might offer.
Impact of Obesity on Pregnancy and Fertility
Obesity has far-reaching consequences throughout the entire pregnancy journey—from before conception through to childbirth. It can contribute to a host of complications for both the parent and the baby. Individuals with obesity are more prone to undergoing labor induction, cesarean sections, preterm births, complications with anesthesia, postpartum hemorrhaging, surgical wound issues, blood clots, and even postpartum depression. Encouraging even a small amount of weight loss prior to conception can lead to significantly improved pregnancy outcomes.
Weight Loss Medications and Fertility
A 2018 review of existing research found that women affected by obesity have a threefold higher risk of infertility compared to those with a healthy weight. A key contributor is polycystic ovary syndrome (PCOS), which disrupts normal ovulation due to hormonal imbalances. Factors like insulin resistance, obesity, and genetic predisposition play a major role in PCOS development. Managing obesity or related conditions such as diabetes can help lessen PCOS symptoms.
Certain weight loss medications may improve fertility by normalizing menstrual cycles. Because of this, some users may become pregnant without immediately realizing it—especially if their periods are typically irregular. This is believed to be part of the reason behind the sudden, unexpected pregnancies seen among users of GLP-1 drugs like Ozempic. Nonetheless, irregular periods aren’t the whole story.
Researchers are currently studying whether GLP-1s and dual agonists like GLP-1/GIP could potentially be used to treat infertility in the future. The FDA has also urged pharmaceutical companies to build pregnancy registries to track outcomes in those who conceive while on these medications.
GLP-1s and Birth Control
For those wishing to prevent pregnancy, GLP-1-based weight loss medications might not be ideal. Tirzepatide, sold as Mounjaro for diabetes and Zepbound for obesity, comes with a warning: it might reduce the effectiveness of oral contraceptives. Since this class of drugs slows down digestion, it can interfere with how the body processes other medications. Individuals in this situation should be counseled to consider birth control options that don’t rely on hormones.
Are Weight Loss Medications Safe During Pregnancy?
Although some weight loss medications may boost fertility, none of the currently approved drugs—including GLP-1s—are considered safe for use during pregnancy. For instance, phentermine (sold under names like Adipex and Suprenza) has been linked to adverse fetal outcomes, including strokes. It’s not just prescription medications that are concerning—herbal supplements marketed for weight loss have also been connected to miscarriage. Similarly, the medical device Plenity is not recommended for pregnant individuals.
Another issue is whether losing weight during pregnancy—regardless of method—is safe. Diet and exercise have been shown to improve pregnancy outcomes. A 2012 study published in the British Medical Journal found that lifestyle modifications can lower the risk of preeclampsia and gestational diabetes significantly. However, introducing weight loss medications into the mix creates a completely different set of questions.
Recent data, including a study published in early 2024 focusing on patients with type 2 diabetes, suggest that GLP-1 drugs don’t appear to increase the likelihood of major birth defects compared to insulin. Still, most available research has only involved animals. Erdem Hospital continues to monitor emerging studies to provide the most accurate information possible.
Should Pregnant Women Stop Taking Weight Loss Medications?
One question that often arises is whether someone should immediately discontinue GLP-1 medications such as Ozempic, Wegovy, or Zepbound once they find out they’re pregnant. According to current guidelines, these drugs should ideally be discontinued at least two months before trying to conceive. But what happens if the pregnancy is unplanned?
Providers need to discuss potential pregnancy scenarios with patients before prescribing weight loss medications. If pregnancy occurs, GLP-1 use should cease right away. This sudden discontinuation might trigger withdrawal effects, including quick weight regain. Healthcare professionals must assist patients in transitioning away from medication by emphasizing sustainable lifestyle changes.
Weight Loss Medications and Breastfeeding
Individuals with obesity are statistically less likely to breastfeed. Several factors contribute to this, including delayed onset of milk production. Despite these challenges, breastfeeding has well-documented health benefits, and patients of all body types should receive support in this area.
Just as they are not recommended during pregnancy, most weight loss drugs are also unsuitable during lactation. For GLP-1 medications, the main concern is the lack of reliable data. It’s unknown whether these drugs pass into breast milk or what their effects might be on infants.
Furthermore, losing weight too quickly after giving birth can itself interfere with milk production. Restarting weight loss treatments during breastfeeding may therefore pose additional risks. As with pregnancy, the safest course may be to encourage patients to stick to nutrition and exercise until more research clarifies the implications of medication use during the postpartum period.
There’s one case report involving a male patient who restarted semaglutide after taking a break. While not directly relevant to pregnancy or breastfeeding, it suggests that patients restarting these medications should begin with a low dose and gradually increase it. Of course, one isolated case does not offer a reliable basis for clinical decision-making.
Alternative Weight Loss Methods During Pregnancy
So, are weight loss medications safe to use while pregnant? At this point, we simply don’t have enough evidence to say so. The safest route is to help patients reach a healthy body weight before pregnancy occurs. That said, not every pregnancy is planned.
At Erdem Hospital, experts play a vital role in guiding expectant patients. It’s important to educate them about appropriate weight gain during pregnancy and to clarify that gaining weight is a normal and necessary part of the process. However, too much weight gain can lead to complications, both during delivery and beyond. Patients should also be evaluated for common comorbidities such as sleep apnea, blood sugar issues, and cardiovascular risks.
For those already pregnant and carrying excess weight, providers should emphasize three of the four core components of obesity treatment: healthy eating, regular physical activity, and behavioral changes. (The fourth component—medical treatment—is typically avoided during pregnancy.) By treating obesity as a medical condition rather than a moral failure, clinicians can help relieve some of the stigma and psychological burden that many pregnant patients already carry.