When an egg is not fertilized by sperm, this causes the breakdown of the uterus lining. It is known as menstruation.
The oxytoxic makes the uterus to become hard.
Pregnancy.
It is controlled by the uterus. That is where the uterus lining is which causes the menstrual cycle
Oxytocin.
Menstruation
call your doctor
When the egg don't get fertilized it will come out and since it will not attach in the uterus, the lining of the uterus will change and that is when you bleed. When you are pregnant there are no eggs dropped and the uterus is closed for the baby to be safe.
The myometrium
uterus compression
Oxytocin causes the uterus to contract. Oxytocin is released by the posterior pituitary gland.
Ulcers typically happen in the cervix, which is the bottom portion of the uterus. The ulcers are commonly caused by STD's and should be treated by a doctor.