Читать книгу Need to Know Fertility, Conception and Pregnancy - Harriet Sharkey - Страница 118

The fertilized egg implants into the lining of the womb. Doctors still do not fully understand just how this critical event occurs, but they do know that if the lining of the womb (the endometrium) is not ready for the fertilized egg, that implantation may fail. This lack of preparation might be due to insufficient progesterone, the hormone that prepares the lining of the womb for implantation, or it might be because the lining of the womb does not respond to the progesterone. This can be found in somewhere between 3 and 20 per cent of couples with a fertility problem. However, much of this information is not consistent and at present there is no good evidence that treatment can improve this. Furthermore, its role as a cause of infertility has been questioned. Doctors therefore do not routinely check the lining of the womb to evaluate its suitability for implantation.