Diethylstilboestrol (DES) is a synthetic form of the female hormone oestrogen. It was prescribed between 1938 and 1971 to women to ensure healthy pregnancies and prevent miscarriages.

Use of DES declined in the 1960s after studies showed that it was not effective in preventing complications during pregnancy.

Women who were given DES while pregnant — often called ‘DES mothers’ — may have a slightly increased risk of breast cancer.

The daughters of women who used DES while pregnant — often called ‘DES daughters’ — are at increased risk of some cancers, including clear cell adenocarcinoma (a rare type of cancer of the vagina and cervix), and have a slight increased risk of breast cancer. They may also be at higher risk of premature birth, miscarriage, ectopic pregnancy and early menopause.

There is no link between DES and cancer in sons or grandchildren of women who used DES while pregnant.

Follow the links below to find out more about DES.