Scientists have discovered an enzyme that acts as a 'fertility switch', in a study published in Nature Medicine today. High levels of the protein are associated with infertility, while low levels make a woman more likely to have a miscarriage, the research has shown.
The findings have implications for the treatment of infertility and recurrent miscarriage and could also lead to new contraceptives. Around one in six women have difficulty getting pregnant and one in 100 women trying to conceive have recurrent miscarriages, defined as the loss of three or more consecutive pregnancies.
Researchers from Imperial College London looked at tissue samples from the womb lining, donated by 106 women who were being treated at Imperial College Healthcare NHS Trust either for unexplained infertility or for recurrent pregnancy loss.
The women with unexplained infertility had been trying to get pregnant for two years or more and the most common reasons for infertility had been ruled out. The researchers discovered that the womb lining in these women had high levels of the enzyme SGK1. Conversely, the women suffering from recurrent pregnancy loss had low levels of SGK1.
The team found further evidence of SGK1's importance in experiments using mouse models. Levels of SGK1 in the womb lining decline during the fertile window in mice. When the researchers implanted extra copies of the SGK1 gene into the womb lining, the mice were unable to get pregnant, suggesting that a fall in SGK1 levels is essential for making the uterus receptive to embryos.
The research at the Institute of Reproductive and Developmental Biology (IRDB) at Imperial College London was led by Professor Jan Brosens, who is now based at the University of Warwick. "Our experiments on mice suggest that a temporary loss of SGK1 during the fertile window is essential for pregnancy, but human tissue samples show that they remain high in some women who have trouble
|Contact: Simon Levey|
Imperial College London