Tall women at greater risk of ovarian cancer
Being heavier also ups the chances of developing the disease in many women, researchers found.
A significant increased likelihood of ovarian cancer was seen for every extra five centimetres in height.
This remained true even after taking account of a host of other risk factors including age, menopausal status, smoking, alcohol consumption, family history, and the use of oral contraceptives or hormone replacement therapy (HRT).
However, body weight appeared to have no impact on women undergoing hormone replacement.
The findings are especially relevant in high income countries, where women have been getting taller and larger over a number of decades.
In parts of the world such as the US and UK, the average height of women has increased by about one centimetre every 10 years. Their body mass index (BMI) - a measurement of weight related to height - has also risen by around one unit per decade.
If other factors remained unchanged, these increases would have resulted in a 3% decade increase in ovarian cancer incidence, say the scientists.
The research was conducted by the Collaborative Group on Epidemiological Studies of Ovarian Cancer, an international team of more than 100 experts based at Oxford University.
They analysed data from 47 studies involving 25,157 women with ovarian cancer and 81,311 healthy women.
The scientists wrote in the online journal Public Library of Science Medicine: “The increase in ovarian cancer risk with increasing height and with increasing body mass index did not vary materially by women’s age, year of birth, ethnicity, education, age at menarche, parity, family history of ovarian or breast cancer, use of oral contraceptives, menopausal status, hysterectomy, or consumption of alcohol and tobacco.
“However use of hormone therapy for the menopause attenuated the relationship with body mass index, since an increase in ovarian cancer risk with increasing adiposity was found only in never-users of such therapy.”
- Collaborative Group on Epidemiological Studies of Ovarian Cancer. Ovarian Cancer and Body Size: Individual Participant Meta-Analysis Including 25,157 Women with Ovarian Cancer from 47 Epidemiological Studies. PLos Medicine 2012; Advance online publication.