ACOG guidance advises stopping GLP 1 drugs one to two months before conception
The American College of Obstetricians and Gynecologists advised against GLP 1 drugs in pregnancy and against their use while breastfeeding preterm infants or newborns. It said safety data remain too limited to call the drugs safe.
What's new
ACOG issued a practice advisory on GLP 1 drugs around pregnancy: consider stopping one to two months before conception, avoid them in pregnancy, and avoid them when breastfeeding preterm infants or newborns.
Why it matters
Use of these peptides among people of reproductive age is rising fast, while human safety data in pregnancy remain limited and mostly observational.
What's next
ACOG said it will monitor new evidence and update the advisory; large prospective studies of fetal growth, child outcomes and breast milk are still missing.
New ACOG guidance tells obstetricians to advise patients to consider stopping GLP 1 drugs one to two months before trying to conceive. The American College of Obstetricians and Gynecologists issued the practice advisory on October 23 and recommended against using the drugs during pregnancy. It also set limits for breastfeeding, advising against use when the infant is preterm or a newborn. ACOG said safety data in pregnancy remain limited and that it will update the advice as evidence grows.
What the ACOG guidance recommends
The document is a practice advisory, a format ACOG uses for issues that need urgent attention because it allows guidance to be written and released quickly. It was developed with D. Yvette LaCoursiere, a professor of obstetrics and gynecology at UC San Diego and the lead author. Before pregnancy, clinicians should explain that safety data are insufficient and that patients should consider stopping one to two months before conception. During pregnancy, ACOG advises against the drugs altogether, and if a patient conceives while taking one, it should not be used for the rest of the pregnancy. Clinicians are also asked to support lifestyle measures and to track weight after the drugs are stopped and through pregnancy.
For breastfeeding, the advisory is less absolute. Clinicians may use shared decision making with patients to build a postpartum care plan that could include a GLP 1 drug. If one is used, the infant's weight gain should be watched closely together with the baby's own clinician. ACOG recommends against use when the infant is preterm or a newborn, which its press release describes as the first 28 days of life. "While GLP-1s are unlikely to be present in breast milk based on early data, there is not adequate safety data or information on the long-term effects," LaCoursiere said in the release. She added that patients who still choose the drugs should prefer those with shorter half-lives.
| Stage | ACOG advice |
|---|---|
| Before conception | Consider stopping one to two months before, then track weight |
| Pregnancy | Advise against use for the whole pregnancy |
| Breastfeeding a term infant | Shared decision, with close checks of infant weight gain |
| Breastfeeding a preterm infant or newborn | Recommend against use |
Why exposure in pregnancy is rising
ACOG framed the advisory as a response to how widely the drugs are now used. Prescribing of GLP 1 drugs around pregnancy rose more than thirtyfold between 2019 and 2024, according to a large records study the advisory cites. A 2024 KFF poll it quotes found that 12% of US adults had ever used one, and that about one in five current users got them through an online prescriber or a medical spa. "Currently, as many as 1 in 300 women are exposed to GLP-1s prior to pregnancy," LaCoursiere said. The advisory also notes that unapproved compounded versions are easy to find online, including for weight control in people who do not have obesity.
Prescribing of GLP 1 drugs around pregnancy rose more than thirtyfold between 2019 and 2024, according to a large records study the advisory cites.
Two features of the drugs raise the chance of exposure. Most have long half-lives, especially semaglutide, tirzepatide and dulaglutide, so they can stay in the body for days or weeks after the last dose, and the advisory includes a table of half-lives for each product. Weight loss on the drugs may also improve fertility. ACOG points to a 2022 randomised trial in which women with obesity and infertility conceived spontaneously more often on exenatide than on metformin. For that reason, the advisory says people who can become pregnant should be counselled on effective contraception while taking these medicines. Planning ahead matters more with long acting products.
What the pregnancy safety data show
The evidence on harm to the baby is thin rather than alarming, the advisory suggests. In animal studies, exposure during pregnancy was linked to lower fetal weight, growth restriction, bone development problems and reduced food intake by the mother. In people, no consistent pattern of birth defects has been reported. A scoping review of 13 articles on pregnancies conceived during treatment found no significant rise in major congenital anomalies, and four recent meta-analyses found no statistically significant increase in malformations, miscarriage, stillbirth or preterm birth. ACOG warns that these rest on a small number of observational studies with uneven control for confounding, and one analysis flagged a possible link with urinary tract malformations based on unadjusted data.
Other studies point to effects on the mother. In a cohort of nearly 150,000 single pregnancies, people exposed to GLP 1 drugs from three years before conception into early pregnancy gained more weight in pregnancy, 13.7 kilograms against 10.5, and had higher rates of preterm delivery, gestational diabetes and high blood pressure disorders than matched controls. A second large study found similar links with semaglutide, but no significant difference between people exposed in pregnancy and former users. The advisory reads this as a possible rebound effect after stopping the drug rather than harm from exposure in the womb. A 2025 study, by contrast, linked use before pregnancy with modestly lower rates of several complications.
The risk of stopping and what comes next
The advisory treats stopping the drugs as a risk in its own right. Weight regain is common once therapy ends, and it may raise the chance of obesity related complications and faster weight gain in pregnancy. "Unfortunately, regaining lost weight is common and may increase the risk of adverse outcomes linked to obesity and excessive gestational weight gain," said Amy Valent, chair of ACOG's obstetrics clinical consensus committee. Rebound effects have appeared in other settings too, such as the loss of glucose control seen after adults with type 1 diabetes stopped semaglutide. ACOG also warns that eating less on these drugs can leave gaps in vitamins and minerals that matter before, during and after pregnancy.
The ACOG guidance is advice to clinicians, not a regulatory rule, and it does not change any drug label. It joins other recent caution over use of these peptides outside standard care, including Japan's ketosis warning for slimming use. ACOG also cites a European obesity society position that data are too limited to recommend obesity drugs in pregnancy or lactation. It said it will watch new evidence and update its advice. Key gaps include large prospective studies of fetal growth and child development, and data on breast milk volume and composition, which the release calls unclear. The recommendations are summarised in the ACOG announcement of October 23.
Conclusion
The new ACOG guidance sets a clear default: plan to stop GLP 1 drugs one to two months before conception, avoid them in pregnancy, and use them while breastfeeding only after a shared decision and never with preterm infants or newborns. The evidence so far shows no consistent pattern of birth defects, but it is too thin to call the drugs safe in pregnancy. Anyone taking these drugs who plans a pregnancy should talk to their clinician before stopping or changing treatment.
