Observational StudySenescent Endometrial Cells in Patients with Thin Endometrial Lining

Patients following long-term use of oral contraceptives with known thin endometrial lining (less than 7mm, confirmed in at least two cycles and unresponsive to estrogen-induced growth).

We will ask each woman to undergo an endometrial biopsy as part of the study during their luteal phase.

Patients with Asherman's syndrome following Dilation and curettage (D\&C). We will ask each woman to undergo an endometrial biopsy as part of the study during their luteal phase.

Patients already scheduled to undergo an endometrial biopsy for infertility management.

We will ask each woman to undergo an endometrial biopsy as part of the study during their luteal phase. In some cases, we may be able to access archived endometrial samples from women in the control group who agree to participate and who have already had an endometrial biopsy.

An endometrial biopsy is the removal of a small piece of tissue from the endometrium, which is the lining of the uterus. Endometrial biopsies are commonly done to check for the window of implantation, to determine ovulation or for enhancing implantation (procedure called endometrial scratching). For this purpose, we will use a "Pipelle" catheter. This procedure is very common in gynecologic practice and

generally considered safe. In most of the cases this procedure is indicated for evaluation of irregular vaginal bleeding, vaginal bleeding in post-menopausal women and for infertility related problems (recurrent implantation failures for example).