In Sweden, a baby girl’s parents were shocked when her genitals started changing. Her clitoris became larger and started to look like a small penis. Her labia also started to fuse, making her genitals appear more like a boy’s. The surprising cause? Her father had been using testosterone gel on his chest.
This kind of gel is a medicine used by some men who have low levels of testosterone, the male sex hormone. It helps them feel more energetic and improves things like muscle strength, mood, and sex drive. But it’s a very strong medicine and if someone else touches the area where it’s been applied, they can absorb the hormone too.
After the baby girl was born, her father often did “skin-to-skin” contact with her, also called kangaroo care. This is when a parent holds a baby directly on their bare chest to help the baby feel safe, warm, and bonded. However, the father did not know that the gel on his chest could be dangerous. By lying on his skin, the baby was accidentally exposed to the testosterone.
At just 10 months old, her parents noticed the changes and took her to the doctor. Tests showed she had high levels of testosterone. The doctor, Professor Jovanna Dahlgren, said she has seen about six similar cases all caused by hormone creams or gels being transferred to children during normal contact with a parent.
In another case, a 10-year-old boy grew breasts after being exposed to estrogen cream used by his mother.
The good news is that in the baby girl’s case, her body started returning to normal after her father stopped using the gel and she was no longer exposed.
Doctors say these medicines are very powerful. They are warning people who use hormone creams or gels like testosterone or estrogen to be very careful. If you use these gels, wash your hands after putting it on. Also, do not let others, especially children, touch the area where the gel was applied unless you’ve washed it off first.
In the U.S., testosterone replacement therapy (TRT) is becoming more popular. In 2019, there were over 7 million prescriptions. In 2024, that number rose to more than 11 million. Even some famous people like Joe Rogan, Sylvester Stallone, and Robert F. Kennedy Jr. have talked about using it. On TikTok, many young men are showing off their bodies after starting TRT.
But experts warn that TRT has side effects. These include:
- Acne
- Swelling from fluid buildup
- Smaller testicles
- Lower sperm count and fertility
- Trouble sleeping, especially with sleep apnea
If you or someone you know uses testosterone gel, remember: it’s strong, and it can affect others especially babies and children through skin contact.