It Starts With An Egg

Egg health is not set in stone

The lifecycle of an egg is not only fascinating but also crucial to your fertility. The process is called folliculogenesis and it prepares eggs for their ultimate purpose—ovulation.

Let’s start at the beginning…

Nearly 2 million eggs develop at about 20 weeks in a female fetus. Many are lost or reabsorbed in a process call atresia, but at birth nearly 1 million remain.

However, these eggs stop developing at what is called the primordial.  This means that any growth, development, or cell division is arrested at birth.  Things don’t get going again until puberty when a young girl has her first period, menarche. 

The stages of growth…

During each cycle in preparation of ovulation, each egg transitions through 3-4 stages:

Primordial

Preantral

Antral

Atresia (for all but the dominate egg)

Anywhere from 300-1000 eggs (follicles) are recruited each month (a few each day) and it will take these eggs 290 days to reach full maturity.  That’s 10 menstrual cycles! During that time they will mature and grow from 15 micrometers to 20 millimeters ideally (at least for the dominant follicle).

Why the timing matters…

The preantral stage is thought to be hormone independent.  The follicle and the egg inside respond only to local signals and the immediate ovarian environment. 

The antral stage is said to be hormone dependent, and the follicle is set to respond to outside signals like FSH (follicle stimulating hormone) and LH (luteinizing hormone) from the pituitary gland in the brain which both stimulate the eggs to prep them for ovulation.

During this stage, the body chooses the most mature and well-developed egg from the recruited pool as the dominant follicle to ovulate and be for fertilized.  This selection process happens at the end of the previous cycle and the dominate egg takes about 15-20 days to fully reach the ovulatory stage…which is why ovulation happens in the middle of the next cycle!   

Many women will have an antral count or will measure their AMH levels to get an idea of overall egg health and reserve. The antral count shows how many eggs have matured to the antral phase and the AMH level is a measurement of this stage since the AMH hormone is released now as well.

Both values can show an approximation of egg health—BUT neither are set in stone.

This final antral stage lasts for nearly 120 days and during that time the growth, health, and quality of the follicle and egg can be most influenced…for better or for worse. The most influential contributor to egg/follicle health is oxidative stress. This is an internal stress that harms all cells. It is caused by inflammation, toxins, external stressors, and a decrease in the body’s natural defenses (normally supported by antioxidants). And all of these can be affected by age and other lifestyle factors like stress, sleep, nutrition, exercersie, digestion and others that were discussed in a previous post about the anchors of fertility and the root causes of low fertility. It is crucial to understand that chromosomal abnormalities are initiated during the antral stage, often caused by oxidative stress.

Ovulation is not the end…

Let’s not forget the the life of the follicle doesn’t end at ovulation when the egg inside is released. A healthy follicle is also needed to produce adequate levels progesterone which is needed to support early pregnancy and avoid early miscarriage.

Lifestyle and nutrition changes needed to reduce oxidative stress must take place while the eggs are maturing to be effective.  One down side of IVF is that it focuses on the last 2 weeks of the process that is actually months long.  By then the health, development, and quality of the eggs are basically already determined.  To be effective, intentional fertility supporting processes and health improvements should already in place. 

What does it mean…

Egg health, egg quality, AMH, and antral count….these are all fluid fertility qualifiers.  You can positively—and negatively—impact your fertility through your lifestyle habits and practices. The anchors of fertility are what supports the fundamental elements that impact your preconception health and womb readiness.  Nutrition is important but so is focusing on whole body health to create a good ovarian environment for your growing eggs.   

Creating your fertile lifestyle can make a difference in your egg health—because it all starts with an egg.  And you have more control than you think. Find your own fertility flow. Start now, it’s never too late.

If you are looking for more answers, consider further testing to finally understand your egg health.

xx and baby dust,

Ericka