To know how does
Regestrone work for periods, you have to understand how periods come.
The
uterus is lines by a thin lining called as endometrium.
When the eggs are growing in the ovary, the follicle in which they are growing produces a hormone called as oestrogen. This oestrogen is responsible for the growth of the endometrium.
When the eggs are released, then the remaining part of the ruptured follicle secretes another hormone called as
progesterone along with the oestrogen. Progesterone makes the endometrium secrete.
These changes are for the reception of the anticipated fertilized egg. If the
pregnancy does not happen then the remaining follicle dies and both the hormones die out. Thus there is no support for the endometrium and it dies out and is thrown out of the body along with some amount of blood in the form of menstrual flow. In short, I put it this way - "
Menstruation are the bloody tears shed by Mrs. Uterus in the sorrow of not becoming pregnant."
Registrone is Progesterone preparation. When consumed, it raises the progesterone levels as long as it is being consumed, making changes in endometrium. Within 3-4 days, there levels come down and thus endometrium starts breaking to effect the menses. This is how it delays the menses as long as you are taking it.
However, if it is to be taken for delaying menses, you should start such preparation at least a week prior to the expected date of menstruation, continue till the date you do not want it to appear and then stop. After about 4-5 days the menses will appear. Please be sure to take such medicines only with Gynaecologist's advice.
Delaying the menses with hormones like this should not be a habit and should be practised sparingly, lest the risk of irregularity in menses or
hormonal imbalance.
I hope you got the answer with a thorough explanation. :)