Checking your Egg Reserve
The Ovarian Reserve
So let’s look at the eggs initially. A woman’s egg reserve, as we’ve already seen, is at its maximum when she’s in her mother’s womb. As she begins to menstruate, she has just under half a million eggs. And of course, by the point of trying to conceive and perhaps having fertility difficulties, the number of eggs have dropped.
But how good is your egg reserve? And what tests can you do to look at this. Well, as we know already at the very start of the menstrual cycle, the body starts to recruit an egg from the pool of follicles in the ovary. As this happens, FSH levels rise in the blood and in a woman whose egg reserve is quite low or depleted, FSH levels will have to work very much harder to recruit an egg for release in the cycle.
And so therefore, by testing at the very start of the cycle, your FSH and LH levels, you can get a feeling for whether that patient has the right hormones working at the right level, or whether in fact there’s a deplete ovarian reserve. And these are very basic tests that should be done by your family doctor or your GP.
And so if you go to see them, please expect blood tests because this is the cornerstone of the first initial investigations of your own fertility.
How do you know if you are releasing your eggs? It’s a really common question and it worries so many people. In general, if you have a regular monthly menstrual cycle between 25 to 35 days, it’s likely that you’ll be recruiting eggs reliably and releasing eggs. One way in which you can check, as we’ve already said and talked about, is home testing kits to check for ovulation but we know following ovulation, there’s a rise in progesterone in the blood, and it’s a blood test, which a GP will often ask you to do on day 21 of a 28 day cycle, which will tell us where the progesterone levels have risen to an optimal peak level for fertilization and implantation.
Anti-mullerian hormone or AMH is another key investigation used by doctors and clinicians to understand a woman’s ovarian reserve. All of a women’s eggs are stored in her ovaries throughout her lifetime, and this is reflected by dormant follicles sitting in the ovaries waiting to be recruited in a menstrual cycle.
It doesn’t matter at which point you test AMH in your menstrual cycle but it will give you a reflection of the store of eggs and the eggs left ready to be recruited. A low AMH level can reflect a deplete ovarian reserve, depending on the woman’s age, and a very high egg reserve will possibly be reflected by a very high AMH.
And this is seen in conditions such as polycystic ovaries. As you get older, a patient’s AMH level is expected to fall, but understanding what is normal and where your AMH level is, is an important part of understanding when to move forwards, perhaps with fertility treatments, if not having success naturally.
AMH quite simply is a measure of your egg store. It does not reflect your chances of natural conception. Neither does it reflect egg quality. In fact, there is no really good test available to determine a woman’s egg quality. Thinking quite simply about it for a moment. Imagine your ovaries represent a large jar of sugar and each grain of sugar, a small, dominant, dormant follicle.
All that your AMH is really telling you is how full the sugar jar is. As you get to the bottom of the sugar jar, the sugar is still good and is not necessarily poor quality. So therefore, having a deplete ovarian reserve or a low AMH level does not tell us that a woman cannot conceive and that the eggs that she has are poor.
Nor does a very high egg reserve mean that eggs are of higher quality. AMH is more a scale of the egg store that a woman has in her ovaries and her ovarian reserve is measured most accurately by AMH.