Contraceptive pill and ovulation
The pill is only 60 years old, which is actually not a very long time in terms of medical history: ovulatory cycles are interrupted with contraceptive drugs and replaced with hormones that are not estradiol and progesterone (with two exceptions where there is estradiol). There are some types of combination pills that use estradiol, bioidentical estradiol, but the progestin is still -- progestin, not a progesterone. And some of these progestins like levonorgestrel are more like testosterone than progesterone. Progestins do not have the same beneficial immune-modulating or beneficial effects on the brain. No progestin converts to allopregnanolone, that beneficial neurosteroid mentioned above.
In addition, taking the pill turns off the synthesis of endogenous progesterone. Not surprisingly, there is research finding that women on the pill have an altered brain structure compared to women who are not on the pill and that taking the pill is associated with an increased risk of anxiety and depression even after the pill is discontinued. Progesterone is very important for the brain.
Not all types of hormonal contraceptives block ovulation. Combination pills (estroprogestin), Nuvaring, Depo injection do. Progestin-only pills and implants mostly do, although it is still possible to have a proportion of estrogen present.
The hormonal IUD with levonorgestrel (Mirena, Jaydess) is different in that it does not stop ovulation, or rather it does in the first year, especially in younger women when the dose is higher, the dose that is levonorgestrel is the drug in the hormonal IUD and then: but afterwards ovulation resumes. So as paradoxical as it sounds:
with the hormonal IUD you are potentially able to have a menstrual cycle but without bleeding, whereas with the pill you have pill withdrawal bleeding, which is not menstruation, but you don't have a period since ovulation is blocked. So: what's the point of having the annoying pseudomenses with the pill if I can do without it since I don't ovulate anyway?
But we need the hormones, so we need ovulation!
