Ovarian volume Assessment
As we learned previously, a woman has her peak number of eggs (oocytes) before she is born. All during a woman’s life, the eggs are degenerating. Literally, tens of thousands of eggs are lost every year of her life! This is one of the main reasons why a woman’s fertility decreases as she gets older.
As the eggs are being lost, the ovaries become smaller. Using transvaginal ultrasound, the volume of each ovary can be calculated by measuring the length, width and depth.
Once you know the ovarian volume, ovarian reserve, ovarian volume, ovary size, decreased ovarian reserve, time to menopause, reproductive ageyou can calculate a woman’s “reproductive age”. Her reproductive age may be older or younger than her actual age.
For example, a 35 year old woman with very small ovaries may have the reproductive age of a 40 year old. Alternatively, a 40 year old with very large ovaries, may have the reproductive age of a 35 year old.
The graph to the right is from a recent article in the medical journal Human Reproduction. Each line represents women of a different age group.
A=25 years old
B=30 years old
C=35 years old
D=40 years old
E=45 years old
In the example above, we used a woman who was 35 years old (line C). If her ovarian volume was 6 mL (read off the vertical axis), her reproductive age would be expected to be that of a 35 year old (read of the horizontal axis). If her ovarian volume was 5 mL then her “reproductive age” would be 40. If the ovarian volume was 11, her “reproductive age” would be closer to that of a thirty year old.
Medical studies have correlated ovarian size with a woman’s ability to respond adequately to fertility medications. Women with small ovaries tend to respond more poorly to fertility medications than women with larger ovaries.
Studies have also correlated IVF pregnancy rates with ovarian volume.
A very recent study has also suggested that you can predict how many years it will be before a woman reaches menopause by her ovarian volume.
Ultrasound can also be used in other ways to determine ovarian reserve. Click here to learn more about determination of the antral follicle count or return to the ovarian reserve testing or clomid challenge test pages.