Mounjaro (Tirzepatide) During Pregnancy: What to Know

What does the evidence say about mounjaro during pregnancy?

1. The January 2026 FDA Mounjaro label says human pregnancy data are insufficient to evaluate major birth defects, miscarriage, or other outcomes. Rat and rabbit studies found fetal growth reductions, and rats had fetal abnormalities at clinically relevant exposure alongside reduced maternal weight and food intake. 1
2. MotherToBaby estimates that in healthy adults it can take up to about 30 days for most tirzepatide to leave the body. This is a clearance estimate, not a label-mandated preconception waiting period or proof that every person clears it on that schedule. 2
3. Endotext recommends considering a switch from a noninsulin injectable to insulin before pregnancy for type 2 diabetes and identifies insulin as the preferred pregnancy agent. It also cautions against stopping current diabetes medicine before an effective transition because hyperglycemia is harmful. 3
4. ACOG states that insulin is the recommended medication during pregnancy when lifestyle changes do not adequately control gestational diabetes and that insulin does not cross the placenta. Individual regimens still require dose selection and monitoring by the pregnancy care team. 4
5. The current FDA label advises adding a barrier method or switching from oral hormonal contraception for four weeks after starting Mounjaro and for four weeks after every dose increase because delayed gastric emptying can reduce oral contraceptive effectiveness. 1

Is mounjaro safe in each trimester?

• First trimester. Human first-trimester outcome data are insufficient, while animal findings occurred during organ formation. If pregnancy is recognized while using Mounjaro, contact the prescriber promptly to plan the next dose, glucose checks, and transition rather than allowing diabetes to go unmanaged.
• Second trimester. Insulin is the preferred medicine for type 2 diabetes during pregnancy. A coordinated switch matters because both high glucose and medication changes can carry risk, and insulin needs may change as pregnancy progresses.
• Third trimester. Continue the pregnancy diabetes plan and glucose monitoring set by the obstetric and diabetes teams. Poorly controlled pregestational diabetes is associated with preeclampsia, preterm delivery, stillbirth, and excessive fetal growth, so stopping glucose management without an effective replacement is not appropriate.