It may come as a shock to you that females are born with all the eggs they will ever have. This means as a woman ages, her egg quality and quantity begin to decline. Let’s break down those terms, what that means, and what to do.
Egg quantity is the number of eggs a woman has. As mentioned, it’s currently believed that a woman will have the greatest amount of eggs she will ever have when she is actually still in her mother’s womb. That number will continue to decrease as she ages, most notably after age 35. Each month, a woman has a certain number of eggs that are available to ovulate. In a normal healthy cycle, one egg will be picked at random to ovulate and the others will essentially die. A woman in her 20’s and early 30’s will likely have many eggs to choose from to ovulate each month. During her late 30’s and early 40’s there will be less eggs to choose from. After age 45, there are usually not many eggs left at all.
Egg quality refers to the genetic makeup of an egg. A normal egg is one that can result in a healthy, genetically normal or euploid pregnancy. This egg should contain 23 chromosomes. An abnormal egg is one that is unhealthy. It generally will not result in pregnancy or may lead to early pregnancy loss. This type of egg is called aneuploidy and may have missing or extra chromosomes. As discussed, a woman has a certain amount of eggs available to ovulate each month. Of those eggs, some will be normal & some will be abnormal. A woman in her 20’s and early 30’s will likely have more normal eggs available to choose from each month, meaning a higher chance she will ovulate a normal egg and become pregnant. As she ages, the ratio of good to bad eggs will shift and there will be a higher chance of ovulating an abnormal egg, meaning a lower chance of pregnancy.
There is unfortunately no real test for egg quality. The most accurate test for egg quality is to look at a woman's age and make predictions based on this biological factor.
Finding out your egg quantity however, can be done fairly simply with what is called ovarian reserve testing. A combination of blood tests along with an ultrasound can give you a good picture of how many eggs you may have left.
Follicle Stimulating Hormone (FSH) & Estradiol
FSH & estradiol are hormones that can be measured through a blood tests. These tests should be drawn around day two or three of your menstrual cycle for most accurate results about your ovarian reserve.
FSH is a hormone produced by the pituitary gland that helps tell the body to begin to develop a follicle for ovulation. If FSH is high at the beginning of the cycle, it means the body is working harder than normal to develop an egg and is generally a sign of declining fertility.
Estradiol is a hormone produced by the growing egg. As it increases, it gives the body the signal to decrease FSH production. A high estrogen level at the beginning of the menstrual cycle, may make the FSH level less accurate. An elevated estradiol level early in the cycle may be a sign of lower ovarian reserve or may simply mean there are hormones remaining from the previous month's ovulation.
Anti-mullerian Hormone (AMH)
AMH is another blood test that can look at ovarian reserve and can be drawn at any time during your cycle. AMH is a hormone made by the follicles, the fluid filled sacs that hold eggs. Measuring AMH is thought to be representative of the remaining egg supply a woman has. A high level of AMH correlates with more eggs and a lower AMH level correlates with fewer eggs.
Antral Follicle Count (AFC)
An antral follicle count can be obtained through a transvaginal ultrasound. During this ultrasound, a doctor or sonographer will look at both ovaries and count the follicles in each. This can tell you how many eggs you have available that month and can help predict how many you will have in the months to come.
Human reproduction declines with age, so the more proactive you can be about your reproductive health, the better. Many women get pregnant in their late 30’s and 40’s without any issues, so age is not always an indicator of fertility but can be a good guide. If you’re worried about your egg quantity, check in with your OBGYN to see if they can order ovarian reserve testing. The more information you have and the sooner you start, the more options will be available to you.
Currently, there isn’t anything you can do to change the quantity of eggs you have. There are some things that can affect your egg quantity and quality that you can change right now to increase your chances of getting pregnant.
Stop smoking
Smoking can speed up the rate at which you lose eggs, meaning your quantity of eggs decreases at a faster rate than someone who is a non smoker.
Avoid toxins in food and products
The Environmental Working Group identifies 12 chemicals that are considered endocrine disruptors or chemicals that can alter your hormones. These chemicals found in food sources, personal care products, and everyday household items can cause unwanted hormonal shifts that may lead to reproductive problems. Check out the full list here: https://www.ewg.org/research/dirty-dozen-list-endocrine-disruptors#.Ww8mcz-WzuQ
Eat a Healthy Diet
In general, it’s recommended to eat a diet rich in organic fruits and vegetables that are minimally processed. Cutting down highly processed foods, trans fats and sugary beverages can improve your overall fertility. Check back with us in the next few weeks for an in depth look at what nutrients and supplements and best for conception!
For more tips on how to improve overall fertility check out our blog post: How To Prepare For Pregnancy