Females on birth control are not protected from pregnancy if they start using weight loss jabs such as Mounjaro and Ozempic, new evidence indicates.

Some women have unexpectedly fallen pregnant after taking weight loss medications despite being on birth control.

More than 450 people are members of a group on Facebook called ‘I got pregnant on Ozempic’, allowing them to share their experiences of accidently getting pregnant while taking semaglutide – the main ingredient of the weight loss injection.

Losing weight can increase fertility because it can correct hormonal imbalances that are triggered by metabolic disorders and obesity, experts have said.

In addition, doctors have revealed that weight loss jabs can lower the efficacy of birth control pills, making it more likely for women to fall pregnant.

On TikTok, one social media user said: “I got pregnant on Ozempic and was on the pill. Baby boy is due in June.”

Meanwhile, another said: “My surprise Ozempic baby is almost four months old and thankfully very healthy.”

Deb Oliviara started using Ozempic in a bid to lose weight. The 32-year-old was on a birth control pill but did admit she was not consistent in taking it.

Due to a history of fertility issues, Deb did not think she would fall pregnant; however, she found out she was expecting a child two months after she started using Ozempic.

She said: “We were open to the idea, but definitely not trying. It was very much a surprise and the only pregnancy, aside from my first, that didn’t come after a loss.”

This is Deb’s sixth pregnancy, but after experiencing two miscarriages and stillbirth, she only has two living children. Currently 10 weeks pregnant, Deb and the baby are healthy.

Novo Nordisk – the drugmaker of Ozempic – has advised that two months before a planned pregnancy women should stop using the weight loss jab.

Reproductive endocrinologist Dr Allison Rodgers said: “It’s true that, from a scientific perspective, these medications may make it easier for people to get pregnant. But people need to be careful because there could be dangerous consequences if taken while pregnant given the drugs can linger in your system.”

Dr Utsavi Shah, Assistant Professor of Bbstetrics and Gynaecology specialising in Obesity Medicine at Baylor College of Medicine in Houston, said: “There is nothing in particular about the medications that is making people more fertile, other than the way they interact with birth control pills.

“It’s their effect on weight loss that’s helping regulate their menstrual cycles, thereby increases their chances of getting pregnant.”

According to the experts, Mounjaro and Zepbound make the stomach take longer to clear out, affecting how oral medications are absorbed in the body.

Dr Shah said: “If you’re using effective birth control and on these weight loss medications, the risk of unintended pregnancy is quite low.”

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