13/11/2024
REGARDING TIRZA..Semaglutide should be stopped at least 2 months prior to conception, and tirzepatide should be stopped 1 month prior to conception, according to the manufacturers. (Boots and Goldberg listed the Canadian label recommendation for stopping tirzepatide, noting there is no suggested timeline for stopping prior to conception on the US label.)
Numerous studies have shown rapid weight regain is common when stopping GLP-1s, which presents a unique set of risks for pregnant women including early pregnancy loss, gestational diabetes, preeclampsia, and nonelective cesarean delivery.
Weighing Risks, Benefits, and Unknowns
Early looks at small human data sets, mostly involving semaglutide and earlier short-acting GLP-1s, and their impact on the risk for birth defects are “reassuring,” Boots said.
“But birth defects are just one small aspect. There’s also metabolic health and things like that long-term. Understanding what it does to the growing baby and the proximity of that medication to that growing baby is really important to see, and can’t be answered with animal studies, not perfectly anyway,” Boots said.
There are no published reports, from clinical trials nor case collections, examining the use of tirzepatide among pregnant people.
photo of Joshua Halpern
Joshua Halpern, MD, MS
“One of the most important questions we need to answer is the preconception safety of these medications, and that includes safety for men,” said Joshua Halpern, MD, MS, an adjunct assistant professor of urology at Northwestern University’s Feinberg School of Medicine, and chief scientific officer for Posterity Health, in an email to Medscape Medical News.
“For example, a recent study found that men who were taking metformin, another popular medication for diabetes, were more likely to have children with birth defects, compared with those who were not taking the medication,” Halpern said. “Further studies are needed to determine whether a similar effect might hold true for the GLP-1 agonists.”
Small early studies on s***m are encouraging, Halpern said, suggesting that GLP-1 use may be beneficial, but a better understanding of direct effects is needed.
Among women, there may be cases where continuing use of a GLP-1 during pregnancy may offer benefits that outweigh risks, Boots suggested. Manufacturers have also created pregnancy exposure registries to measure the safety of their therapies during pregnancy.
“I have a group of patients whose sugars are so well controlled on these medications, but as soon as they come off, they get weight regain and their glucose is just so poorly controlled,” she said. “There may be a group of women where the benefits of glucose control outweigh the risks of being on the medication the whole pregnancy.”
The list of important unknowns also includes a need to examine how rapid weight loss may impact ovulation rates and spontaneous conception, as well as miscarriage rates, birth weight, and metabolic health of the child.
photo of Jacqueline Maya MD
Jacqueline Maya, MD
More detailed rebound weight gain data is coming next year, with additional analysis expected as well on birth weight and pregnancy outcomes, said Jacqueline Maya, MD, first author of the research abstract presented at this year’s American Diabetes Association conference that examined gestational weight gain among people with preexisting type 2 diabetes who were exposed to GLP-1s during pregnancy. The study included 47 exposed pregnancies (based on prescription records and electronic chart information) and compared gestational weight gain to 141 unexposed matched pregnancies. Among the exposed group, 62% exceeded recommended weight gain, compared with 41% in the unexposed group. On average, gestational weight gain in exposed pregnancies exceeded that among matched unexposed pregnancies by about 6 pounds.
The team is now working with an additional data set to examine exposed pregnancies among people with obesity, said Maya, an instructor of pediatrics at Mass General Hospital and Harvard School of Medicine. She is particularly interested in examining weight trajectories during pregnancy to see how they may affect fetal outcomes. Her team’s current project also will likely include analysis to examine other variables like postpartum weight gain and adiposity characteristics of the baby.
Maya said the team hopes to have more to report at the American Diabetes Association conference in June next year.
Offer the Conversation
Using a GLP-1 for weight loss takes time, usually around 1 year to reach a plateau. Boots encouraged nonfertility providers to ask patients of reproductive age about their family plans as an opening.
“I hope for all primary care doctors and gynecologists, that with any patient of reproductive age, you should be bringing this up, asking, ‘Have you thought about having kids? Are you thinking about it soon?’ And if they say they are sometime in the near future, then you can say, ‘Is it OK if I bring up your weight?’ And you should ask permission.”
If the patient declines, it’s OK to bring it up again at a future visit.
“People with obesity have often experienced negative weight bias that impacts their care,” Jimenez said. “Treat obesity as a disease, not a personal failing. Ask permission to discuss weight with the patient beforehand. If they say no, respect that answer. This goes a long way in developing a positive relationship, so they return for care and may be willing to discuss later.”
When patients are open to the conversation, Boots suggests not focusing on the potential for poor outcomes, and instead perhaps saying, “If you’re thinking about having a baby in 5 years, optimizing your health now will not only make your pregnancy healthier, but your child healthier long-term.”
Discussing contraception plans remains important. People starting semaglutide or tirzepatide should use contraception other than oral birth control for 4 weeks while starting the medicine and for 4 weeks after each dose increase.
Boots said that the contraception conversation is particularly important because many people have come to deeply believe that they are infertile and, thus, may perhaps think contraception advice doesn’t apply to them. Maya hypothesized that behavioral changes following weight loss may also be a pathway toward pregnancy.
“Pregnancy while on GLP-1 RAs does happen. I always have a discussion about this possibility and contraception. This can sometimes be challenging for people with infertility to consider,” Jimenez said. “Explaining the risks, benefits, and unknowns can help. As the [Fertility and Sterility] paper describes, the limited data available has not shown increased fetal or maternal complications. We need more high quality data to better understand the impact of exposure or use around the time of conception and during pregnancy.”
It’s also important to introduce the idea to patients that they may someday need to come off the medications, such as when they are ready to have children, and how important lifestyle and behavioral changes will be at that time, Maya said.
“We do know what the alternative is, and we do know what the risks of obesity are,” she said. “So, it’s a tug and pull. We’re not starting off with healthy. We’re starting off with a disease that is physically and emotionally very difficult for the patient, especially when it starts in childhood.”
Medscape
