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Do Weight-loss Drugs Cause Unplanned Pregnancies?

May 20, 2024

You’re watching social media videos, say, and see formerly overweight women crooning about how they got pregnant thanks to weight-loss drugs.

That’s not the whole story, so let’s delve into the details.

Weight-loss drugs are not fertility drugs. Some women taking these popular medications do, indeed, find themselves with child — but not for the reasons they’re saying. There are dangers involved, so do your research.

If you find yourself struggling with fertility and believe your excess weight might be part of the cause, talk to your doctor about weight loss options — including the new weight-loss drugs. However, you should not be trying to conceive while on these medications.  

What’s the Fertility/Weight-Loss Drug Connection?

Several medications designed to help diabetics control their blood sugar happen to be good for weight loss, too. They’re known medically as GLP-1 receptor agonists. They decrease appetite or in other ways result in patients eating less food, and therefore shedding pounds quickly.

Overweight women who lose a lot of weight frequently become more fertile — but not from the pills or injections. Strict diets, rigorous exercise, bariatric surgery and/or weight-loss medications can all help you shed pounds and therefore increase your fertility.

Once your BMI dips into the moderate range, you might start ovulating regularly when you hadn’t before. If your excess weight contributed to polycystic ovary syndrome, or PCOS, that might ease up after trimming down too; the reasons involve insulin resistance. You also might produce too much estrogen, and your body may resist elements of fertility treatments.

So, yes, weight-loss drugs might increase fertility simply because being severely overweight can hurt fertility.

Possible Birth Control Pill Connection

The medical community confirms that pregnancy rates rise when women lose weight on these drugs, as they do through other weight-loss methods.

Many doctors suspect that there is also a chemical connection: Some elements of the GLP-1 receptor agonists might make birth control pills less effective. If that is the case, and you’re on both birth control pills and weight-loss meds, you might be more likely to conceive than you were before.

Nobody knows for sure yet. Studies are underway, yet the connection has not been proven scientifically.

Add a Physical Barrier to your Birth Control Arsenal

Since you’d take birth control pills to avoid pregnancy, reassess your contraceptive choices. The goal: to get pregnant when you are not on a weight-loss medication.

Either supplement your birth control pills with a physical barrier or change methods altogether.

  • Condoms add a physical barrier. Combined with the pill, it will cut down your chances of conceiving.
  • IUDs, short for intrauterine devices, are inserted into your uterus to prevent ovulation.
  • Etonogestrel implants in the upper arm use hormones to prevent pregnancy for three years.
  • A slow-release injection of progestin known as medroxyprogesterone acetate stops eggs from being released.

Dangers of Getting Pregnant While on Weight-loss Drugs

These drugs are new, so researchers are still assessing what effect if any they might have on a fetus.

It’s best not to have any non-crucial pharmaceuticals in your blood while you’re trying to conceive. You’d take multivitamins and decline margaritas when trying to have a baby, right? So consider clearing weight-loss drugs from your body also.

If you are on a weight-loss drug and want to get pregnant, take these steps:

  • Continue until you reach a healthy weight and start ovulating regularly. During this time, use an effective barrier or LARC (long-acting reversible contraception) method of birth control. Studies have shown you’re likely to have fewer complications if you conceive and have a baby after achieving a BMI of 18.5 to 24.9. In addition, babies born to mothers who have risk factors from being overweight are at increased risk for some health problems.
  • Go off the drug for two months before you try to conceive. This allows time for the medication to clear out of your body. You can start taking it again once you give birth and stop breastfeeding.
  • Eat healthy foods, even if you fear gaining back some weight. Your baby needs nutrients and depends on you to provide those by choosing a varied diet consisting mostly of non-hyperprocessed foods.
  • With a go-ahead from your OB/GYN, start trying to have your family.

Be careful to time your pregnancy for when you want it. Beforehand, take extra care to choose a form of birth control that is guaranteed to be effective. You might not be able to be evaluated by a doctor before reaching six to eight weeks of pregnancy.

Your medical team will guide you to achieve your goal weight and also make sure you have the right contraception if you need one. When you are ready to plan for a pregnancy, talk to your doctor, who will help guide you into a healthy and happy journey for you and your baby.