A newborn girl in Sweden started developing male-like genitalia after spending time lying on her father’s bare chest. He had been using testosterone gel, but no one realised it was transferring directly to her skin, reports Vice magazine.
The case, revealed by paediatric endocrinologist Professor Jovanna Dahlgren to local outlet Göteborgs-Posten, isn’t a one-off. She said she had seen at least six children in similar situations. In one case, a 10-year-old boy developed breasts after coming into contact with his mother’s oestrogen cream.
In this case, the baby’s clitoris became enlarged and elongated and her labia began to fuse. Blood tests showed elevated testosterone levels, and doctors traced it back to the father’s medication. Once he stopped using the gel, the child’s body began returning to typical female anatomy.
TRT, or testosterone replacement therapy, has become increasingly popular in recent years. Prescriptions in the United States jumped from 7.3m in 2019 to more than 11m in 2024, according to CBS News, while TikTok is filled with men in their 20s and 30s boasting about before-and-after results.
TRT is often marketed as the cure for “manopause”, a term used to describe the natural decline in testosterone that begins around age 40.
The hormones can boost energy and sex drive, but they can also cause acne, shrunken testicles, low fertility, and mood swings. The gel, in particular, is risky when people don’t follow strict safety protocols.
According to the Mayo Clinic, anyone using a topical hormone cream should wash their hands after applying it and rinse the treated area before touching others.
In this case, the father had no idea his chest was dosing his newborn. What began as standard “kangaroo care”, the skin-to-skin bonding practice between babies and parents, became a medical emergency.
The incident happened years ago but continues to resurface as a cautionary tale. Even the phrase “micropenis”, while technically inaccurate in this context, has grabbed headlines and fuelled confusion.
The condition wasn’t a penis at all, but virilised female genitalia triggered by hormone exposure.
No charges were filed. No long-term damage was reported. But doctors are urging parents and providers to treat hormone treatments with more respect.
Vice article – Baby Girl Grew a ‘Micropenis’ From Lying on Her Dad’s Chest (Open access)
See more from MedicalBrief archives:
About 25% of men with testosterone issues delay treatment – UK study
'T-boosters' not effective in improving testosterone levels
Pros and cons of growing trend of testosterone therapy for women
Experts warn against over-prescription of testosterone for women