Girls who are tall and lean in childhood are more at risk of endometriosis, study finds

'It really tells us that the roots of this disease lie earlier in life than people have previously thought,' says author Dr Jennifer Baker

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Girls who are tall and lean during childhood are more at risk of developing endometriosis later on in life, a study has found.

Researchers from the University of Copenhagen and Frederiksberg hospital looked at height and weight data from 170,000 women born in Denmark between 1930-1996, and hospital records of endometriosis or adenomyosis (a related condition) collected between 1997-2017.

Endometriosis, the NHS says, is a common condition where tissue similar to the lining of the womb starts to grow in other places, such as the ovaries or fallopian tubes.

Symptoms include pain in your lower tummy, abnormal levels of period pain that interrupts daily life, pain during sex, feeling sick, being constipated and difficulty getting pregnant.

It is believed that up to 10 per cent of women live with the condition, with some left infertile as a result of it not being treated.

In the recent study, authors looked at the correlation between weight, height and endometriosis diagnosis and found that the condition is more common among women who were tall and lean in their youth.

Overall 2,149 women were diagnosed with endometriosis, and 1,410 with adenomyosis from the sample size, and it was more likely in those with a lower childhood body mass index (BMI).

For seven-year-old girls of an average height, a child of average weight has an 8 per cent lower risk of endometriosis than a child who weighed 2.3kg less.

By the age of 13 if you compare two girls of average height, the one who weighs 6.8kg less has a six per cent increased risk of endometriosis.

The study also reveals that being taller as a child is linked to a greater risk of endometriosis – a finding previously noted in adults.

“Body size during these ages is an indicator for later risk,” said Dr Jennifer Baker, a co-author of the research. “It really tells us that the roots of this disease lie earlier in life than people have previously thought,” she said.

The authors say one possible explanation for the link is that both body size and endometriosis may be linked to oestrogen levels: the hormone promotes growth of the lining of the womb as well as growth spurts during puberty.

But the link with BMI is less clear: a higher BMI, and greater weight, has previously been linked to a greater production of oestrogen – yet the latest study suggests a higher BMI is protective against endometriosis.

“It is a very complex association and it may not be [the] same pathway between BMI and height,” said Baker.

The study has limitations, including that most participants were white.

In addition, endometriosis is thought to be under-diagnosed and this study only relies on hospital-recorded diagnosis and does not take into account those who are undiagnosed.

Celebrities including Lena Dunham, Alexa Chung, Gabrielle Union and Daisy Ridley have all spoken before about living with endometriosis.

Endometriosis Awareness Month takes place every March to raise awareness of the condition.