What is the normal size of a woman’s endometrium?

The endometrium has a very important role in achieving a pregnancy, since it is the uterine lining which the embryo implants in. The endometrium is a tissue that changes throughout the ovarian cycle to achieve receptivity at the time of embryo implantation. Two hormones operate during endometrial preparation: oestrogen and progesterone. 

Endometrial thickness is usually around 6 to 10 mm. This generally coincides with days 19-21 of the menstrual cycle, which is when the endometrium is receptive. This period of time is known as the implantation window.

Endometrial thickness and appearance are the factors that must be considered when predicting the success of a fertility treatment. An trilaminar endometrium between 6-10 mm at the time of follow-up is a sign of good endometrial response to the treatment. It is hard to set an exact cut-off point in order to know whether implantation will occur or not, given that it is a complex process and there are other factors that affect it. Having a trilaminar 8 mm endometrium does not mean that we know with certainty that the embryos will implant. On the other hand, there may be patients that can achieve a pregnancy with a 6 mm lining. Each case must be evaluated and treated individually. Therefore, do not wait any longer and get in touch with us.