PATHOLOGY

Detailed explanation-1: -If fertilization does not occur, the endometrium, coupled with blood and mucus from the vagina and cervix (the lower, narrow part of the uterus located between the bladder and the rectum) make up the menstrual flow (also called menses) that leaves the body through the vagina.

Detailed explanation-2: -After conception, a fertilized egg travels through your fallopian tubes to your uterus. The fertilized egg (called an embryo) implants (attaches) into the wall of your uterus. This triggers the placenta to form. Your placenta begins producing and releasing human chorionic gonadotropin (hCG) into your blood and pee.

Detailed explanation-3: -The lining of the uterus (endometrium) starts to thicken. One of the ovaries releases an egg. And then, if the egg isn’t fertilized or a fertilized egg doesn’t attach to the lining of the uterus (implant), the endometrium sheds from the uterus as a menstrual period.