GLP-1 and Pregnancy
The rise in the use of GLP‑1 receptor agonists—such as semaglutide (Ozempic, Wegovy), liraglutide (Saxenda), and dulaglutide—has transformed the management of type 2 diabetes and obesity in the UK. If you are pregnant, planning a pregnancy, or navigating fertility while using a GLP‑1 medication, you may be seeking clear, evidence‑based guidance. Understanding what current research shows, and what remains uncertain, can help you make informed decisions in collaboration with your healthcare team.
GLP‑1 receptor agonists work by mimicking the incretin hormone GLP‑1, which stimulates insulin release, slows gastric emptying, and reduces appetite. Their effectiveness is well‑documented: clinical trials show average weight‑loss outcomes of 10–15% of body weight with semaglutide and 5–8% with liraglutide. These medications have therefore become increasingly common among people of reproductive age. However, their use during pregnancy remains an area of caution.
Current UK guidance, including recommendations from NICE and the Medicines and Healthcare products Regulatory Agency (MHRA), advises that GLP‑1 medications should not be used during pregnancy. This recommendation is based on limited human data and concerning findings from animal studies, where exposure to GLP‑1 agonists has been associated with fetal growth restriction, skeletal abnormalities, and pregnancy loss. While animal studies do not always predict human outcomes, the potential risks have led to a precautionary approach.
Human data are emerging but remain limited. A 2024 systematic review of available case reports and registry data found no clear pattern of congenital anomalies among infants exposed to GLP‑1 medications in early pregnancy. However, the sample sizes were small—fewer than 300 documented exposures worldwide—and therefore insufficient to establish safety. Evidence Based Birth and other research‑translation organisations emphasise that the absence of evidence is not evidence of absence, and that robust, long‑term studies are still needed.
For this reason, NICE guidance recommends discontinuing GLP‑1 medications at least two months before conception for semaglutide and one month before conception for liraglutide, reflecting their differing half‑lives. This washout period is designed to ensure the medication is fully cleared from the body before pregnancy begins. The Great Birth Rebellion highlights that many people conceive unexpectedly while using GLP‑1 medications, and that compassionate, non‑judgemental support is essential in these situations. Current evidence does not suggest a need for pregnancy termination solely due to early exposure, but enhanced monitoring may be recommended.
Breastfeeding while using GLP‑1 medications is also not currently recommended. There is insufficient evidence on whether these drugs pass into human milk, and animal studies show measurable transfer into milk. UNICEF UK emphasises that medication safety during lactation must prioritise infant wellbeing, and until more data are available, GLP‑1 medications should be avoided during breastfeeding.
The emotional landscape surrounding GLP‑1 use and pregnancy can be complex. Many people experience significant improvements in health, mobility, and wellbeing while using these medications, and the prospect of discontinuing them may feel daunting. Others may feel anxious if they discover they were pregnant while taking a GLP‑1 medication. These feelings are valid. Evidence‑based care must include not only clinical guidance but also emotional support, continuity of care, and clear communication.
As research evolves, our understanding of GLP‑1 medications in pregnancy will continue to grow. For now, the safest approach is to avoid GLP‑1 use during pregnancy and breastfeeding, plan conception with appropriate washout periods, and seek personalised guidance from your healthcare team. Your wellbeing and your baby’s wellbeing are central, and you deserve care that is grounded in evidence, compassion, and respect.
References NICE Guidance – Obesity: Identification, Assessment and Management
https://www.nice.org.uk/guidance/cg189
MHRA – Safety Information on GLP‑1 Receptor Agonists
https://www.gov.uk/drug-safety-update
Evidence Based Birth – Medication Safety and Pregnancy Research Summaries
https://evidencebasedbirth.com/
UNICEF UK Baby Friendly Initiative – Breastfeeding and Medication Safety
https://www.unicef.org.uk/babyfriendly/
Royal College of Obstetricians and Gynaecologists – Preconception Advice
https://www.rcog.org.uk/
