GLP-1 and Birth Control: Semaglutide and Oral Contraceptives

The key concern

You are considering starting a GLP-1 medication and you take oral contraceptive pills. You want to know: will the medication affect your birth control?

The short answer is that it depends on the medication. The Zepbound (tirzepatide) label warns that tirzepatide may make birth control pills less effective, with the largest effect after the first dose.^[2] The Wegovy (semaglutide) label does not include that warning.^[1] The most important step is to tell your prescriber which birth control you use before you start.

How GLP-1 affects medication absorption

GLP-1 receptor agonist medications slow gastric emptying. This means the stomach releases food and liquids into the small intestine more slowly than normal. This is part of how the medications reduce appetite and lower blood sugar.

But there is a practical consequence: if your stomach is emptying more slowly, medications taken by mouth can be absorbed differently. Both labels say this delay may affect the absorption of oral medications taken at the same time.^[1][2]

For oral contraceptives specifically, the concern is absorption of the hormonal components (such as ethinyl estradiol and a progestin). If absorption is delayed or reduced, the contraceptive could be less effective.

What the research actually shows

The labels report different findings for the two medications.

Semaglutide (Wegovy). In clinical pharmacology trials with semaglutide 1 mg once-weekly injection, semaglutide did not affect the absorption of oral medications.^[1] The label’s drug interaction data list no clinically significant change in ethinyl estradiol or levonorgestrel levels with semaglutide.^[1] The Wegovy label does not include a contraceptive warning or a pill-timing instruction for the injection. For Wegovy tablets, the label says to wait at least 30 minutes after taking the tablet before eating, drinking, or taking other oral medications.^[1]

Tirzepatide (Zepbound). In a study described on the Zepbound label, a single 5 mg dose of tirzepatide taken with a combined oral contraceptive lowered overall exposure to the pill’s hormones by about 20 percent, and peak levels dropped further.^[2] The label says this delay is largest after the first dose and lessens over time.^[2]

Because of this, the Zepbound label tells prescribers to advise patients who use oral hormonal contraceptives to switch to a non-oral method, or add a barrier method, for 4 weeks after starting tirzepatide and for 4 weeks after each dose increase.^[2]

Label information applies to the brand-name products studied.

Oral contraceptives vs. other birth control methods

This interaction concerns oral contraceptive pills. The Zepbound label says hormonal contraceptives that are not taken by mouth should not be affected.^[2] Non-hormonal methods do not rely on hormone absorption at all.

Methods not expected to be affected:

• Hormonal intrauterine devices (levonorgestrel IUDs)
• Contraceptive implants
• Birth control injections
• Hormonal patches
• Vaginal rings
• Barrier methods (condoms, diaphragm)
• Copper IUDs

If you are concerned about the interaction with oral contraceptives, or if you are planning to start tirzepatide, ask your prescriber whether one of these methods fits your situation.

Practical guidance: what to do if you take both

Before starting GLP-1 treatment:

Tell your provider. When you talk with your prescriber, mention your current birth control method. A careful prescriber should review the label instructions for your medication with you.

Know your medication’s label. If you start tirzepatide and take birth control pills, the Zepbound label calls for a non-oral method, or a barrier method added to the pill, for 4 weeks after starting and for 4 weeks after each dose increase.^[2] The Wegovy label does not include this instruction.^[1] If you take Wegovy tablets, follow the label’s instruction to wait at least 30 minutes before taking other oral medications.^[1]

Ask about backup contraception. On tirzepatide, a backup or non-oral method is a label instruction during those windows.^[2] On semaglutide, ask your prescriber whether a backup method makes sense for you.

Watch for irregular bleeding. If you experience breakthrough bleeding, spotting, or other changes to your usual menstrual pattern after starting GLP-1, contact your prescriber. It may be a sign of reduced pill absorption, or it could be due to other factors. Your prescriber can help determine the cause and adjust your plan if needed.

Discuss your timeline if planning pregnancy. If you are thinking about becoming pregnant in the near future, discuss the timing with your prescriber. GLP-1 medications are not used for weight loss during pregnancy, and the labels differ on when to stop.^[1][2]

A note for perimenopausal women

Many women in their 40s and early 50s are starting GLP-1 medications while navigating the perimenopause transition. Some in this age group may not be using hormonal birth control at all, either because they have already entered menopause or because they prefer non-hormonal methods.

If you have had your final menstrual period, are using a non-hormonal contraceptive method, or are not using any contraception, the GLP-1 and oral contraceptive interaction does not apply to you.

However, if you are in perimenopause (where periods may be irregular but still occurring) and you do use oral contraceptives, the guidance above applies.

Pregnancy and GLP-1 medications

The labels say weight loss offers no benefit during pregnancy and may cause fetal harm, and to stop the medication for weight loss when a pregnancy is recognized.^[1][2]

If you are planning pregnancy: Discuss your timeline with your prescriber. The Wegovy (semaglutide) label says to stop at least 2 months before a planned pregnancy to account for semaglutide’s long half-life.^[1] The Zepbound (tirzepatide) label says to stop when a pregnancy is recognized and does not list a washout period before a planned pregnancy.^[2] Ask your prescriber how far ahead to stop.

If you become pregnant while on GLP-1 therapy: Contact your prescriber right away. Your prescriber can help you stop the medication and discuss next steps.

If you are not sure about your pregnancy status: If you miss a period or suspect you may be pregnant while on GLP-1 medication, use a home pregnancy test and contact your prescriber. Do not wait to see if your period returns.

In animal studies described on the labels, both medications were linked to fetal harm at clinically relevant exposures, and both labels say human data are insufficient to establish a drug-related risk.^[1][2] That is why a possible pregnancy on a GLP-1 medication should be addressed promptly.

The bottom line

GLP-1 medications slow gastric emptying, which can affect how oral medications are absorbed. For birth control pills, the labels differ: the Zepbound label warns that tirzepatide may reduce pill effectiveness and calls for a non-oral or backup method at set times, and the Wegovy label does not.^[1][2]

If you take oral contraceptive pills:

• Tell your prescriber before starting GLP-1 treatment
• On tirzepatide, use a non-oral method or add a barrier method for 4 weeks after starting and for 4 weeks after each dose increase
• On Wegovy tablets, wait at least 30 minutes after the tablet before taking other oral medications
• Watch for irregular bleeding and report it to your prescriber
• Discuss your birth control method and pregnancy timeline with your prescriber

The Zepbound label says hormonal methods that are not taken by mouth (IUD, implant, patch, ring, injection) should not be affected.^[2]

If you have questions about your specific birth control method or GLP-1 medication, your prescriber can give you personalized guidance based on your health history.

Citations

[1] Novo Nordisk. Wegovy (semaglutide) prescribing information. US Food and Drug Administration. Revised 06/2026. https://www.accessdata.fda.gov/drugsatfda_docs/label/2026/215256s025lbl.pdf (Section 2.1: wait at least 30 minutes after a Wegovy tablet before other oral medications; section 7.2: oral medications; sections 8.1 and 8.3: pregnancy, stop at least 2 months before a planned pregnancy; section 12.3: no clinically significant change in ethinyl estradiol or levonorgestrel.)

[2] Eli Lilly and Company. Zepbound (tirzepatide) prescribing information. US Food and Drug Administration. Revised 08/2026. https://www.accessdata.fda.gov/drugsatfda_docs/label/2026/217806Orig1s041correctedlbl.pdf (Sections 7.2 and 8.3: oral hormonal contraceptive instructions; section 8.1: stop when pregnancy is recognized; section 12.3: contraceptive interaction study.)