Lydia* first started thinking about weight-loss drugs during pregnancy. “Everyone was talking about them and the advertisements were everywhere,” she says, as her baby son naps upstairs. “I remember thinking: ‘That’s how I’ll lose weight for my wedding next year.’”
When Lydia explains that most of her life before pregnancy was spent in a welter of yo-yo dieting and body dissatisfaction, I say to her that I think most of us can relate. Her pregnancy, however, brought a level of body acceptance and contentment that the 33-year-old from Wales had never had before.
But as her due date approached, a familiar feeling of dread emerged. In her antenatal class WhatsApp group – once a space where pictures of their growing bumps and tips on how to get labour started were shared – babies started arriving and so did conversations about feeding. Suddenly, diet and weight loss entered the chat. Out of the group of six mums, three decided not to breastfeed or gave up early to either crash diet or go on weight-loss jabs – both of which are advised against during breastfeeding due to their impact on both milk quality and supply. Lydia was committed to breastfeeding, though, so tried not to let it faze her – and was relieved when, despite her son being very poorly when he was born and ending up in the neonatal intensive care unit, they were able to do it.
Trauma has a habit of focusing the mind, and in the early days of her son’s life, Lydia’s worries about her weight fell by the wayside as she devoted herself to caring for him. “He nearly died. I just didn’t care about anything else other than him,” she says. After a few months, though, she started to notice that her weight had begun to creep up, rather than fall off, as everyone – including her mum – had assured her it would while she was feeding.
Today, at seven months postpartum, everywhere she looks, she sees weight-loss jabs: in her Instagram feed, many of her followers are either on them or talking about them – and many targeted ads are from a private provider. The world, it seems, is ready for her to stop being overweight. And like so many women before her, she is listening. “As much as I can appreciate my body for bringing this beautiful soul into the world and I can completely rationalise it,” she says, “the thought of not being ‘thin’ for my wedding makes me want to die inside.”
I am also a mother to young children and, like many others, have struggled with my weight throughout my life. I grew up in the late 90s, under the toxic lens of obsessive scrutiny of women’s bodies. I still remember presenter Chris Evans asking Victoria Beckham to weigh herself live on TV six months after giving birth to her first son, Brooklyn, to prove that she had lost her baby weight. And although the body positivity years made great strides in helping us all to embrace difference and diversity, the rapid multi-billion-pound growth of the GLP-1 agonist market, which has seen an estimated 1.5 million people in the UK start using the drugs, seems to be pushing acceptance backwards.
I had my first child in 2022 and my second in 2024 – and the pressure to “snap back” after my second was acute; the entire landscape felt different. Weight loss was now not simply aspirational, but possible; just one simple, albeit pretty expensive, injection away. A 2019 study by the Mental Health Foundation estimated that as many as four in 10 women experience postnatal body dissatisfaction – it’s no wonder private weight-loss companies target women who have recently given birth. Just look to Serena Williams’s recent endorsement of the jabs as part of an advertising campaign for Ro, a private provider: “After kids, it’s the medicine my body needed,” she says.
I jumped on the bandwagon six months after giving birth. After researching the drugs and reading the government and NHS guidance around taking GLP-1 agonists, I learned that these drugs should not be taken during pregnancy, while trying to get pregnant, or while breastfeeding. In close second to the numerous bouts of mastitis I suffered in the preceding few months, wanting to quickly lose weight was a huge factor in my decision to give up breastfeeding at six months.
Dr Jan Toledano, a leading women’s hormone specialist and founder of the London Hormone Clinic, says she sees this all too often in her clinic. “It’s such a period of hormonal upheaval. Your body changes, you’re all over the place ... you’ve got the responsibility of looking after these new babies and toddlers. You have all sorts of identity and body issues, and the pressure to go back to how you were before is immense.” She says it is alarming, but not surprising, that someone would be so keen to lose weight in this environment that they’re prepared to stop breastfeeding.
Melanie* is a 31-year-old mum of two small children and lives in south Wales. Her youngest daughter is 18 months old and breastfeeds a few times a day. Fed up with her size postnatally and keen to lose weight, Melanie has been injecting Mounjaro (a popular GLP-1 agonist) since January and has lost five stone. For her, the weight loss has been “life-changing”, although going against NHS guidance wasn’t a decision she took lightly. “I did a lot of research, read science papers as much as I could understand them and spoke to my husband about it,” she says. The private provider she bought her Mounjaro from asked if she was breastfeeding. She ticked a box to say no and the veracity of the information she provided was never checked.
She says she felt more comfortable going against strict guidance as she takes another medication she says is administered in the same way that is deemed safe for breastfeeding. She had also read experiences of other women on Reddit. “Obviously, they haven’t been able to do large-scale studies on the safety of the drugs while breastfeeding, because it’s not ethical,” she explains, “but we decided that we would go ahead.”
The Breastfeeding Network’s Drugs in Breastmilk service provides information on the safety of medications, treatments and procedures when breastfeeding. Amanda Da Costa, clinical supervisor at the service, says that the number of enquiries from breastfeeding mothers about weight loss has gone up 145% from summer 2024 to summer 2025. “Questions about jabs make up the largest reason for those weight-loss-related queries,” she says. “GLP-1 medications such as Mounjaro, Ozempic or Wegovy are not recommended for use while breastfeeding,” she adds. “More research and data is needed on whether these drugs transfer into breastmilk or whether they have any effect on nursing infants.”
Toledano is even more direct in her concern about use of these drugs during breastfeeding. “There’s very little human data on whether they are absorbed in breast milk and passed onto a baby, but there are animal studies,” she says. “They’re not very extensive, but there are some that show that there could be a possible effect on the growth of the baby – so it’s both extremely serious and extremely important that GLP-1s are avoided during breastfeeding.” She also points out that the impact on a baby might not even be visible at first, but there is the potential for long-term consequences. “Other areas of concern for the baby would include development of normal appetite regulation and gut hormone pathways.”
The fact that new parents like Melanie can access these drugs online so easily is concerning. Da Costa says the network expects all prescribers to ask patients whether they are breastfeeding before prescribing, but is quick to say that they know this doesn’t always happen, or that a person may choose not to or forget to disclose this information. For Toledano this lack of oversight is the most troubling aspect of the boom in GLP-1 use via private vendors. “They often advertise that there is nutritional support, but there isn’t,” she says, “and because it’s online and no one can get their eyes on you, how do you make an assessment of how well the patient is?”
Toledano says there are other potential health risks of taking weight-loss drugs during the postnatal period – which she determines as at least the first year of a baby’s life. “If there’s rapid weight loss, this impacts lots of different things: milk production may cease, yes, but also energy levels may decrease, which, in my opinion, would predispose to postnatal depression.” She also notes that losing body mass quickly can lead to a cessation of periods, which could mask the return to fertility that menstruation often indicates. Because of this, she advises anyone taking them to be really careful about contraception if their intention is not to fall pregnant.
There are, of course, some cases in which mothers need medical assistance in the postnatal period, specifically if they have developed gestational diabetes or are at risk of developing type 2 diabetes or other metabolic diseases. In these cases, Toledano advises working with a specialist doctor who can oversee their care as they take the drugs, but she is concerned that the mass marketing of the drugs directly to consumers is interfering with this process. “If a woman is reaching for the GLP-1 agonists because they’re advertised all the time and everyone’s on them, she’s not going to see a doctor who understands metabolic changes after pregnancy,” which, she believes, puts them at risk of developing unwanted side effects or other health complications.
I regret my decision to stop breastfeeding to take GLP-1 agonists — not least because the side effects were intolerable for me, and I was unable to take them for longer than a couple of weeks. Letting your milk supply go isn’t a decision that you can easily go back on. Hindsight is a beautiful thing, of course, but looking back now, I can see how exposed and insecure I was in those early postnatal days, and therefore primed to fall for the promise of easy weight loss. I may as well have had a target painted on my back. And what I do feel now is worry about the lack of continuous care and support for postnatal women who are – rightly or wrongly – being pushed towards these drugs during an extremely susceptible time. I wish someone had protected me from them.
Since our interview, Melanie has told me that she has now stopped taking Mounjaro. She says she is concerned by how easy it is for postnatal women like her to get drawn in by the marketing of the jabs, or to omit information or lie to get hold of them – as she did. “You are quite vulnerable; your hormones are all over the place, lack of sleep and all of that. There should be warnings and stricter advertising so they don’t target the wrong people,” she says.
For now, Lydia has decided not to take the drugs. “Ultimately, my child comes before this incessant need to be thin,” she says, although she is clear that if she is advised it is safe to do so, and she’s confident her son won’t be harmed, she is likely to take them as soon as he turns one. She also resents that, as is often the fate of women, she is having to choose between two things that society places huge pressure on mothers to achieve: bouncing back and breastfeeding. “I just hate that I can’t do both,” she says. I tell her I feel the same.
* Names have been changed
