What are the main causes of female infertility?

Cause of female infertility-
1.    Poor egg quality- Ovulation is a major cause of Infertility. When egg is not released in a female, fertilization cann’t happen. 
2.    Poor Endometrial thickness- Endometrium acts like a bed for the embryo which travels from tubes to uterus. But when the endometrial thickness and circulation is not proper, implantation fails and either abortions happen or patient cant conceive.
3.    Irregular Menstrual cycle
4.    Scanty Menstrual Bleeding
5.    Endometriosis
6.    Adenomyosis
7.    PCOD/ PCOS
8.    Endometriotic  cysts