24-03-2013, 23:46
The main worry is that estrogen does have an effect of tissues of the female repro tract. It can (can, not does) cause the endometrium to grow which could lead to endometriosis. That, of course, can lead to infertility. Estrogen gives positive feedback to the pituitary gland to release a flood GnRH which in turn releases LH and FSH which of course stimulate ovulation and follicle growth, respectively. This means that excess estrogen could lead to ovarian cycsts from over-stimulated ovaries. Progesterone is the main concern when regarding ovulation. Progesterone gives negative feedback which in turn slows GnRH to a drip, which means that no FSH nor LH is released. Since no LH is released, then there is no ovulation. It is possible that long-term P4 can stop ovulation or impair it significantly due to the fact that steroid hormones have an incredibly long half-life because of their structure.
This is information that I am taking from my reproduction class, so it is in no means scientific fact of what will or can happen. There are no guarantees that NBE is safe, it is a risk that we all take. I took PM while on BC (probably a bad idea, but I did grow). I have now stopped both PM and BC and my cycles have returned to normal (although this last one has been long) so I am assuming that I am ovulating and my tract is fine, only time will tell.
This is information that I am taking from my reproduction class, so it is in no means scientific fact of what will or can happen. There are no guarantees that NBE is safe, it is a risk that we all take. I took PM while on BC (probably a bad idea, but I did grow). I have now stopped both PM and BC and my cycles have returned to normal (although this last one has been long) so I am assuming that I am ovulating and my tract is fine, only time will tell.