Why is there a menstrual period while on birth control if no eggs are released?

It's withdrawal bleeding.





Your lining still builds up and must be shed every month even though there is no ovulation.Why is there a menstrual period while on birth control if no eggs are released?
On the combination pill it's a hormonal bleed. It's from the drop in estrogen.


On the mini pill a period usually means ovulation is still occuring.

makeup look