FAQ · GLP-1 · Editorial commentary

What does the published guidance say about GLP-1 medications, pregnancy, and contraception?

Editorial commentary on the published Summaries of Product Characteristics, Patient Information Leaflets, and NHS contraception guidance. The MHRA-approved SmPCs and PILs for tirzepatide (Mounjaro), semaglutide (Wegovy), and liraglutide (Saxenda) state that these medications are contraindicated in pregnancy and during breastfeeding, that women of childbearing potential are advised to use effective contraception, and that the medication should be stopped a defined period before a planned pregnancy. The basis is published animal reproductive toxicology and the absence of human safety data in pregnancy. Decisions about pregnancy planning, contraception choice, and how to act if pregnancy occurs are between the patient, their UK-licensed prescriber, their GP, and their obstetric or midwifery team.

If you are pregnant or think you may be pregnant while on a GLP-1 medication, contact your prescriber and GP the same day. If you cannot reach them and are unsure what to do, call NHS 111. Decisions about pregnancy planning, contraception, and continuation of any medication during pregnancy are clinical decisions for your prescriber and obstetric team, not a general website.

What the SmPCs report

The MHRA-approved Summaries of Product Characteristics for Mounjaro (tirzepatide), Wegovy (semaglutide), and Saxenda (liraglutide) state that use during pregnancy is contraindicated. The published basis is animal reproductive toxicology that identified adverse effects on embryofetal development at clinically relevant exposures, combined with the absence of adequate and well-controlled studies in pregnant women, who were excluded from all pivotal trials. The same documents state that the medication is also contraindicated during breastfeeding.

What the PILs report on pre-conception planning

The Patient Information Leaflets for each medication describe a recommended period for discontinuation before a planned pregnancy. The exact wording and the specific time period referenced are set out in the PIL supplied with each medication and on emc.medicines.org.uk. PeptideClear does not reproduce the period here because the authoritative source is the PIL itself, and because the planning decision is taken with a prescriber, who may individualise the advice based on the patient\'s circumstances. The published pharmacology supporting the recommendation is the medication\'s half-life and the clearance window required to reduce plasma levels.

What NHS contraception guidance reports for women of childbearing potential on GLP-1

NHS contraception guidance lists the available methods of contraception and their relative effectiveness. The Mounjaro PIL contains a separate note on oral contraceptive absorption being affected by slowed gastric emptying (covered on the Mounjaro and contraception page). Choice of contraceptive method, including whether a non-oral option is preferred, is a clinical decision made with a contraception provider or sexual and reproductive health clinician.

If pregnancy occurs unexpectedly while on a GLP-1

Editorial note. The published guidance directs patients to contact their prescriber and arrange early antenatal review. Reporting the exposure to the UK Teratology Information Service (UKTIS) supports ongoing safety surveillance for these medications during pregnancy. The clinical management plan, including the timing of stopping the medication and any additional review by an obstetric team, is set by the prescriber and antenatal team, not by a general website.

Breastfeeding

The published SmPCs for tirzepatide, semaglutide, and liraglutide state that the medications are contraindicated during breastfeeding. Animal data showed transfer into breast milk and the impact on the breastfed infant is reported as unknown. Decisions about restarting any medication after weaning are clinical decisions for the patient and prescriber.

PCOS and fertility planning

Published commentary notes that some women with polycystic ovary syndrome see fertility changes when weight reduces under GLP-1 treatment, which can affect contraception requirements and pregnancy planning. UK clinics that offer combined weight management and fertility planning coordinate the pre-conception discontinuation window with active conception planning. The coordination is clinical work, not something a comparison website can sequence for an individual.

Where to ask

· Your prescriber. NHS GP, NHS Specialist Weight Management Service, private clinic prescriber, or pharmacist prescriber.
· Your GP and NHS maternity service if pregnancy occurs or is being planned.
· UK Teratology Information Service (UKTIS) for safety surveillance reporting of exposure during pregnancy.
· The published SmPCs and PILs on emc.medicines.org.uk.
· Adverse effects can be reported via MHRA Yellow Card.
· NHS 111 if you cannot reach your prescriber.

Decision routing: pregnancy planning, contraception choice, and action if pregnancy occurs are clinical decisions for your prescriber, GP, and obstetric team. This page is editorial commentary on published guidance, not individual advice.