Scientists say they have observed an enzyme that effectively forms a fertility switch and believe the finding could improve existing infertility treatments, help understand miscarriage and even lead to new types of contraceptives.
Their study which is reported in the Nature Medicine this Sunday, outlines how a team at Imperial College London found a protein known as SGK1 appears in high levels in infertile women, while low levels are associated with miscarriage.
Jan Brosens, who led the study at Imperial College and is now at Warwick University, said its results indicate new fertility and miscarriage treatments could be designed around SGK1.
"I can envisage that in the future, we might treat the womb lining by flushing it with drugs that block SGK1 before women undergo IVF (in vitro fertilization) ... Another potential application is that increasing SGK1 levels might be used as a new method of contraception."
Infertility is a problem which affects more than 10 percent of people worldwide and around half will seek some form of medical treatment hoping to have children of their own, usually after trying to get pregnant naturally for a couple of years or more. Additionally around one women in a hundred experiences recurrent miscarriages which are defined as the loss of three or more consecutive pregnancies.
Brosen's team examined tissue samples from the womb lining of 106 women who were being treated for unexplained infertility or miscarriage. The high level of SKG was linked to infertility while the low level was linked to miscarriage. Additionally when studying mice, the SKG level in the uterus declined leading up to the most fertile parts of the mouses cycle and when the mice were implanted with extra SGK1 genes they were unable to get pregnant. Thus conclude the researchers reduced levels of SKG1 play an essential part in preparing the uterus for an embryo.
Obviously though with low levels of SKG1 causing miscarriage any treatment would need to balance the levels, otherwise successful SKG1 infertility treatment might lead to miscarriage after fertilization occurred, and visa versa treating a women who has experienced multi miscarriages by elevating her SKG1 level, might make her infertile.
Madhuri Salker of Imperial college, who also worked on the study concluded :
"Low levels of SGK1 make the womb lining vulnerable to cellular stress, which might explain why low SGK1 was more common in women who have had recurrent miscarriag ... In the future, we might take biopsies of the womb lining to identify abnormalities that might give them a higher risk of pregnancy complications, so that we can start treating them before they get pregnant."
Written by Rupert Shepherd