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What Exactly Occurs During Your Menstrual Cycle?


Today I want to speak to you about the menstrual cycle. Every day, women come to my office with problems with their period. So it is very important to have a good understanding of the menstrual cycle.

Young women start having their periods usually between 9 and 12, and at the beginning, they are very irregular. It takes a while for the whole system to get mature. Usually about ages 14 to 16, the periods start to be more regular, coming every month.

So today, I am going to use an average of a 28 day cycle to think about this. We consider the first day of the period as day 1 of your bleeding. We are going to divide those 28 days into 14 and 14.

In the first part of the cycle, the ovary starts with a little dot and then it grows; an egg grows in the cyst, and then that cyst gets to be about the size of my thumbnail. Around day 14, that cyst opens up and the egg comes out. In those first 14 days, estrogen is the hormone that is made. That estrogen is important in stimulating the lining of the womb.

In the second half of the cycle (the second 14 days), now the ovaries make estrogen and progesterone. The estrogen stimulates the lining and the progesterone supports the lining. When you get to be around day 28, if the person is pregnant, the ovaries continue to make the estrogen and progesterone and there is no bleeding.

If you are not pregnant on the 28th day, what will happen is: the estrogen and progesterone decreases, you have your period, and you start over at day 1.

Irregularities in the menses can cause many problems. It can cause you to have irregular bleeding, heavy bleeding, no bleeding, PMS, cramping with your periods, infertility, and finally, you can be in menopause.

Hopefully with this information, if you have any of these problems, you will now be able to have a better discussion with your health care provider. Wishing you good health, I’m Dr. Michael Polcino. Thank you.

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