The most common causes of endometrial thinning are endocrine disorders, infections and uterine manipulation. Endocrine disorders include low oestrogen levels, ovulation disorders and growth hormone deficiency; acute or chronic uterine infections can lead to destruction of the basal layer of the endometrium, including bacterial infections, reproductive tuberculosis, mycoplasma infections and chlamydia infections.
Clinical operations affecting the endometrium including curettage, hysteroscopic myomectomy, removal of endometrial polyps and laparoscopic myomectomy which penetrates the uterine cavity may damage the endometrium, resulting in endometrial philtrum and uterine adhesions.