Can You Get Pregnant on a GLP-1? What I Tell My Patients

By Dr. David LaMond, Medical Director, Blue Sky MD 

Over the past year there has been a steady stream of stories about women getting pregnant unexpectedly while taking GLP-1 medications. Social media calls them “Ozempic babies.” Most of the coverage treats it as a funny side effect. I don’t. 

Many of the women I treat for weight are in their 30s and 40s. Some are trying to get pregnant. Some very much are not. Both groups need to know two things before they start a GLP-1: these medications can change how reliable your birth control pill is, and losing weight can make you more fertile than you were before.  

Why a weight-loss shot can affect your birth control pill 

GLP-1 medications slow down how fast your stomach empties. That is part of how they work: food sits in your stomach longer, so you feel full sooner and stay full longer. 

It also means anything you swallow, including a birth control pill, can be absorbed differently. For most medications this does not matter much. For a pill that has to keep hormone levels steady every day to prevent ovulation, it can. 

The FDA label for tirzepatide (Zepbound and Mounjaro) addresses this directly. It says tirzepatide may make oral hormonal birth control less effective, especially at the start. The label advises women on the pill to either switch to a non-oral method or add a barrier method, such as condoms, for 4 weeks after starting tirzepatide and for 4 weeks after each dose increase. The effect is largest after the first dose and fades over time, which is why those windows matter. 

Semaglutide (Wegovy and Ozempic) does not carry the same warning. In a study designed to test this, semaglutide did not meaningfully change the levels of birth control hormones in the blood. But there is a second issue that applies to every GLP-1: nausea, vomiting and diarrhea. If you vomit within a few hours of taking your pill, or have severe diarrhea, your body may not absorb it. Those side effects are most common when you start or increase a dose, which is the same window when we are already being careful. Your pill’s own instructions explain what to do after a missed or vomited dose; keep them handy during those weeks. 

What does not appear to be affected: IUDs, the implant, the shot, the patch and the ring. These don’t depend on your stomach, so slower emptying does not change them. 

Weight loss can make you more fertile 

Excess weight, and especially insulin resistance, can interfere with ovulation. Polycystic ovary syndrome (PCOS) is the most common example: high insulin pushes the ovaries to make more testosterone, and ovulation becomes irregular or stops. International PCOS guidelines note that losing even 5% to 10% of body weight can restore regular cycles in many women. 

GLP-1 medications are very good at lowering insulin and producing that kind of weight loss. So a woman who has had irregular periods for years, and has quietly assumed she could not get pregnant easily, may start ovulating again within a few months of starting treatment. If she is relying on that assumption instead of birth control, she can get pregnant without planning to. 

The chain works like this: high insulin → the ovaries make more testosterone → the signals that trigger ovulation get disrupted → cycles become irregular or stop.

Lower the insulin, and the chain can run in reverse. That is why I pay so much attention to fasting insulin in women with irregular cycles, whether or not they carry a PCOS diagnosis. It is also why the change can happen before the scale moves very much. Insulin often improves in the first weeks of treatment, well before the full weight loss shows up. 

I see this as good news. For women who want to conceive, improving insulin resistance and losing weight before pregnancy can make conception easier and pregnancy safer. But it has to be planned. 

If you are planning a pregnancy 

GLP-1 medications are not approved for use during pregnancy. In animal studies, high doses caused problems with fetal growth and development. Human data are still limited. 

The label for Wegovy recommends stopping it at least 2 months before a planned pregnancy, because semaglutide stays in the body for a long time.

At Blue Sky MD we follow that 2-month rule for every GLP-1, including tirzepatide. Most of the medication has cleared well before then, but the extra time builds in a margin of safety. If you become pregnant while taking a GLP-1, stop it and call your provider. 

The early human data are somewhat reassuring. A large study published in JAMA Internal Medicine in 2024 looked at women with diabetes who took a GLP-1 in early pregnancy and found no higher rate of major birth defects compared with women who took insulin. That is helpful if you find out you were exposed before you knew you were pregnant. It is not a reason to keep taking the medication once you know. 

Here is the plan I usually walk through with women who want to conceive: 

1. Use reliable contraception while on the medication, ideally a method that is not a pill. 

2. Get to a healthy weight and better insulin numbers first. That is where the medication helps most. 

3. Stop the GLP-1 at least 2 months before trying to conceive. 

4. Plan for the hunger that returns when you stop. We focus on protein, strength training and regular check-ins so the weight does not come back too quickly. 

5. Start a prenatal vitamin with folic acid before conception, as you would with any planned pregnancy. 

Why I bring this up at the first visit 

A GLP-1 prescription can now be written after a short online questionnaire. Some of those programs never ask whether you could become pregnant or what birth control you use. Pharmacy inserts are long and easy to skip. 

At Blue Sky MD, contraception and pregnancy plans are part of the first conversation for every woman of childbearing age who starts a GLP-1. It takes a few minutes. It lets us choose the right medication, time dose increases around your plans, and avoid the kind of surprise that turns into a story on social media. 

If you are on hormone therapy too 

Many of my patients take hormone therapy along with a GLP-1. That combination works well for body composition and energy, but it adds one more thing to plan for. Testosterone, including the low doses we use in women, should not be used during pregnancy. If you are on testosterone and could become pregnant, reliable contraception matters even more. 

If you are on testosterone and want to conceive, we recommend stopping it up to 6 months before you start trying, and staying on birth control during that time. Testosterone from pellets is usually out of your system within 3 to 4 months; the longer window gives your own hormones time to settle and leaves room for safety. 

Questions to ask before you start a GLP-1 

If you could become pregnant, these are worth settling at your first visit, not after: 

• Which GLP-1 am I starting, and does it affect my birth control? The answer is different for tirzepatide and semaglutide. 

• When are my dose increases? Each one starts a new 4-week window if you take tirzepatide and use the pill. 

• What should I do if I vomit or have diarrhea? Know the backup plan for your pill before it happens. 

• Would a different method make this simpler? An IUD or implant takes the stomach out of the equation for as long as you are on treatment. 

• If I want to get pregnant next year, what is the timeline? Working backward from your goal date makes it much easier to plan the stop and the months after. 

I would much rather have this conversation in the first visit than after a surprise. 

Breastfeeding 

We don’t have enough data on GLP-1s during breastfeeding to call them safe, so we proceed with caution. Making milk takes a lot of energy, and this is not the time to cut calories. A medication designed to reduce appetite works against what your body needs to keep up your milk supply. 

For that reason, I do not start or restart GLP-1 medications while a woman is breastfeeding. We wait until you have finished, then pick the plan back up. 

What I tell my patients 

If you are taking a GLP-1 and you are not trying to get pregnant, take birth control seriously, especially in the first months and after every dose increase. If you use the pill and take tirzepatide, add condoms or switch methods for those 4-week windows, or talk to your provider about an IUD or implant. 

If you are trying to get pregnant, a GLP-1 can be a useful step before pregnancy, not during it. Plan your stop date, and let us help you hold on to your progress afterward. 

Women with PCOS should pay special attention here. And if your periods have been irregular for years and suddenly become regular after starting treatment, assume you can get pregnant. 

If you have questions about your own situation, talk with your Blue Sky MD provider before you start or change anything. Bring your cycle history, your current birth control and your timeline for a family, and we will build the plan around them. 

See if you qualify for GLP-1s and learn more about our GLP-1 + medical weight loss combination program here.

Every patient is different. This article is for general education and is not a substitute for individual medical advice. Talk with your provider about contraception, pregnancy planning and any medication changes.