During Pregnancy the uterus gets totally focused on protecting and nourishing the growing foetus. This means it can't receive eggs as usual because the hormones sent to release the eggs, are being redirected to develop a baby. So, figuratively speaking, it sends out a busy signal. During pregnancy, your body temporarily halts ovulation and stops shedding the lining of the uterus. As a result, you don't have your period. After the baby is born, the body's natural cycle of ovulation returns, and your period returns as well.
If the egg is fertilized and results in pregnancy then the menstrual cycle stops. The menstrual cycle exists to allow pregnancy to occur, so when pregnant no need for it to continue.
During a menstrual cycle, the uterus thickens its lining in preparation for a possible pregnancy. If pregnancy does not occur, the uterus sheds this lining through menstruation. The cycle is controlled by hormones such as estrogen and progesterone.
Pregnancy
The menstrual cycle.
menstruation
At the end of a menstrual cycle, the unfertilized egg is either absorbed by the body or expelled during menstruation. The lining of the uterus, which thickened in preparation for a possible pregnancy, sheds as menstrual bleeding. This marks the start of a new menstrual cycle.
The menstrual cycle seizes once the vagina is done shedding its lining otherwise for it to FULLY seize it would be during menopause or during a time of pregnancy.
Menstruation is one of the phases of the menstrual cycle, whereas the menstrual cycle is the entire reproductive system. During the menstrual cycle an egg is released and to prepare for possible pregnancy the uterus lining plumps-up, if pregnancy doesn't occur the uterus lining sheds (menstruation) so it can start afresh again next cycle.
breaks down
Menstrual cycle is about 28 days that prepares the body for pregnancy.
If you were pregnant then you'd no longer have a menstrual cycle, if you don't understand that then you should in no way be having sex or sexually active to risk pregnancy. The menstrual cycle is your body preparing for possible pregnancy, when pregnant the cycle is shut down.
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