Safety Advice for Weight-Loss Medications During Pregnancy
Women who are using weight-loss injections are being advised to stop if they are trying to conceive, have become pregnant, or are breastfeeding. This guidance comes from drug safety experts in the UK, who express uncertainty about the potential harm these medications, such as Wegovy and Mounjaro, might cause to an unborn baby.
This cautionary message is already included in the patient information leaflets that accompany these medications. However, there’s a growing concern that the rising popularity of these so-called “skinny jabs” means many women might not be using them safely or obtaining proper advice.
Natasha Major, a 26-year-old who began using Mounjaro for weight loss before planning her third pregnancy, was taken aback when she discovered she was pregnant six weeks later—even while on contraceptive pills. “I have polycystic ovaries, so I don’t conceive easily. It was a shock,” she recalls.
Majors’ worries about the health of her baby prompted her to consult her GP, who told her to discontinue the medication. “We’re over the initial shock now and really happy—just unexpected,” she reflects. She had her last injection only hours before learning about her pregnancy. Fortunately, her early scan showed the baby was developing well.
Concerns are echoed by the UK’s drugs regulator and medical professionals about the safety of popular GLP-1 medications, which include Wegovy, Mounjaro, Saxenda, Victoza, and Ozempic. These drugs, designed to aid in weight loss (and treating type 2 diabetes in the case of Ozempic), work by mimicking hormones that signal fullness after meals. They have some availability through the NHS, but with high demand, many seek them out from unregulated sources, often without medical oversight, as a quick solution for weight loss.
As a precaution, the Medicines and Healthcare products Regulatory Agency (MHRA) recommends that women on these medications use contraception while receiving treatment and for a certain period before trying to conceive—specifically, two months for Wegovy and Ozempic, and one month for Mounjaro. Women using Mounjaro and taking oral contraceptives should also consider additional contraceptive methods for a period after starting the drug, as weight-loss jabs may reduce the effectiveness of the pill in overweight individuals.
Importantly, many women, including Natasha, report not receiving adequate information about these risks when obtaining such medications. She mentioned that she “can’t recall reading anything about contraception” related to her purchase.
In response, the MHRA has issued new guidelines on weight-loss injections. The urgency stems from a small number of reports concerning unintended pregnancies and pregnancy complications linked to these medications. Dr. Alison Cave, the chief safety officer at the MHRA, noted that animal studies suggest these drugs could be harmful to unborn babies, but more data is needed to understand the implications for humans. “If you’re using this medication and find out you are pregnant, consult your doctor about stopping it as soon as possible,” she advised.
Sukhi Basra, vice-chairwoman of the National Pharmacy Association, encourages women to seek guidance from their pharmacists if they’re unsure about when to stop taking these drugs. Access to contraception in the UK remains challenging, according to the British Pregnancy Advisory Service (BPAS), citing issues like appointment shortages and long waiting lists.
The BPAS is calling for improved access to reproductive choices for women, emphasizing the need for better resources and options when it comes to contraception.
