Estimating Egg Counts: Millions Dwindle to Diminished Ovarian Reserve
At IVF Plano, we factor in many causes when projecting a woman’s chances for getting pregnant, particularly in an IVF cycle. Dr. Jim Douglas will explain why maternal age and other factors contribute to diminished ovarian reserve, or the dwindling of eggs in your ovaries.
As part of the female infertility workup, we order fertility blood work to help determine how well the body is responding to ovulatory prompts. We can’t know for sure how many eggs a woman has left, but maternal age, genetic testing and fertility testing can help us make an educated guess.
Ovarian reserve testing helps assess a woman’s reproductive health and project how well the body will respond to ovulation stimulation during a fertility treatment cycle. Even younger women can fall under the category of “poor responders.”
Indicators of diminished ovarian reserve may include:
- Maternal age of 35 or older
- Chromosomal or genetic disease (Turner’s Disease or Fragile X)
- Previous damage to the ovaries from surgeries, chemotherapy or radiation
- Pelvic adhesions or tumors
- Immunological conditions
Egg age: The lifespan of a female oocyte
In utero, female ovaries contain a pool of millions of oocytes, or eggs. These reproductive cells grow inside follicles. After her first menstrual cycle, a woman will release one egg, sometimes multiple eggs (think twins!), during ovulation. The egg will travel into one of the fallopian tubes and combine with sperm to create a human embryo.
A female must have a sufficient number of good quality eggs to achieve a pregnancy. Between birth and menopause, the number of eggs naturally diminishes each month until a woman no longer has the capacity to get pregnant.
- Before birth, a female has approximately 6-7 million eggs.
- That number drops to around 1 million at birth.
- By puberty, a woman will have half her eggs left to release each month during ovulation.
- The number of healthy, genetically sound eggs significantly drops after age 35 leading to diminished ovarian reserve. A woman over 40 may have as few as 1,000 eggs and just a 5 percent chance of conceiving in a given month.
Taking action to detect and overcome a low egg count
Women benefit from ovarian reserve testing if they decide to pursue fertility treatment at an advanced age, or are planning to delay starting a family.
AMH testing for diminished ovarian reserve assesses the immature and microscopic pool of primordial follicles. To use a baseball analogy, these are eggs “on deck” for a chance to come to the plate during ovulation. We can run AMH testing at any point in the menstrual cycle.
FSH testing measures the amount of follicle stimulating hormone in the blood on Day 3 of a woman’s cycle. This hormone from the pituitary gland instructs the ovaries to choose and release an egg. At IVF Plano, we consider FSH of XX below normal.
A clomiphene citrate challenge test, in conjunction with FSH testing, artificially stimulates the ovaries and then measures how well the levels drop back to a normal range.
Sonography shows us the progression of growing antral follicles during a normal menstrual cycle.
Additional tests that Dr. Douglas may order include:
If Dr. Douglas determines that we will have fewer eggs to work with in an IVF cycle, he can plan accordingly during ovulation induction. When all signs point to a very low egg supply, we want to avoid needlessly stimulating the ovaries with higher doses of fertility medications.
In some extreme cases, donor egg IVF cycles help women with diminished ovarian reserve achieve a pregnancy.
Today’s advanced reproductive technologies, combined with Dr. Douglas’ 20 years of experience investigating and resolving infertility issues, help women and couples in Plano and Dallas become parents. Contact IVF Plano to schedule a consultation with our top-notch team.