In response to yesterday’s post about the new FDA-approved, no-period birth control pill Lybrel, Alicia asked this question in the comment trail:

What exactly happens to your egg(s) when birth control pills prevent ovulation?

That’s a great question. First of all, let’s be clear on two important facts about the female body:

1. You’re born with all of the eggs you’ll ever need–millions of them, just chilling in your ovaries until menarche.
2. Ovulation refers to the actual release of the egg from the ovary into the fallopian tube, not the production of the egg.

Second, let’s be clear on what happens to eggs that aren’t fertilized and gestated when you’re not taking birth control.

1. At ovulation, the egg is released and travels down the fallopian tube to the uterus.
2. If it’s not fertilized, it simply disintegrates and is absorbed by the lining of the uterus.*

Logically, then, if birth control prevents ovulation from releasing the egg into the fallopian tube, it would eventually just break down and be asorbed back into the body in the uterus. But does that play out scientifically?

From Planned Parenthood of Southeastern Pennsylvania:

Your eggs are just hanging out in your ovaries until they are called upon. Not ovulating doesn’t do any damage to your body, including your eggs.

They don’t all “expire” at the same time, but your eggs have been dying since you were in your mother’s womb.

Girl fetuses have eggs, in fact we have the most eggs (5-7 million) ever when we are still inside our mom developing. A lot of those eggs die before we are even born and they continue to die throughout our life. By the time most of us reach puberty we have about 400,000 eggs left. Which is more than enough!

Some of those eggs get used, some die and some even survive menopause. Really, menopause is sort of an expiration date for the eggs that have made it that far. There may be a few still holding out, but we won’t use them after menopause.

The medical term for this process is atresia, which Stedman’s Medical Dictionary defines as “The degeneration and resorption of one or more ovarian follicles before maturation.”

So, the short answer (after that long one!) is that if the egg isn’t fertilized or if it isn’t even released, the same thing happens: it just gets absorbed back into the body. Amazing, huh?

Contents © Copyright 2007 Kristen King

Post from: Blisstree

Lively Women Q&A: What Happens to Your Eggs When You Don’t Ovulate?