the pill makes your body deficient in b-6 vitamin which lowers progesterone. estrogen starts to dominate and makes progesterone drop low every month. it wont go back to normal til its fixed. sometimes just b-6 in a complex vitamin will fix it and raise progesterone back to normal but it might take a few months. need b-6 with other vitamins or it will make you deficient in the other b vitamins as well. dont want to get preg being deficient in b-12, it helps prevent miscarriage, or folic acid, helps prevent neural tube defects. a b-50 or b-100 complex is best.
if you dont want to wait and see if b vitamins raise progesterone you can supplement with progesterone cream and its immediate!
i used b complex for a few months to get preg with my last son, didnt want to wait around this time. first month using cream got preg