PCOS & Infertility
Affecting about 6-12% of women in reproductive age, polycystic ovary syndrome (PCOS) is a "basket" of different medical conditions, with one finding in common: polycystic ovaries (PCO). In polycystic ovaries, multiple small cysts appear along the outer capsule of the ovaries on ultrasound imaging. PCOS is often associated with infertility, because of anovulation (lack of ovulation) and amenorrhea (lack of menstruation). However, with proper fertility treatments, PCOS patients can usually get pregnant with their own eggs.
How PCOS Causes Infertility: Polycystic Ovaries
PCOS has many variations and has wide-ranging phenotypes (clinical presentations) and associated problems. However, PCOS does have one common characteristic: multiple small cysts aligned along the outer capsule of the ovaries, with an appearance of a chain of pearls on ultrasound. Those little "pearls" are the so-called preantral follicles. Antral follicles are at a very early stage of follicle (egg) maturation. In PCOS patients, follicles and eggs stop developing at the preantral follicle stage. As a consequence, women with PCOS rarely reach ovulation, in which a mature egg would be released from the ovary for potential conception.
Women with PCOS also often (though not always) do not have regular menstrual cycles. Affected women often experience prolonged periods between menstruations, a condition called oligo-amenorrhea. Anovulation and oligo-amenorrhea are frequent characteristics of PCOS. Since a woman cannot conceive without ovulation, PCOS infertility is one of the most common types of female infertility.
PCOS Leading to Diminished Ovarian Reserve Later in Life
Another major misconception about PCOS is that this condition remains static over time. It most definitely does not; various authors recently reported that the clinical expression and severity of PCOS decline with advancing age. It is not uncommon that we see patients presenting with an old diagnosis of PCOS, and after some testing, they turn out to suffer from diminished ovarian reserve (DOR)(DOR) , a condition in which ovaries no longer produce a good number of high-quality eggs. At younger ages, they may have indeed suffered from PCOS with too many follicles developing at one time, but by the time they present for infertility treatment at our NYC fertility center, they have “burnt through” their egg reserve and gone on to develop diminished ovarian reserve. From a state of excessive follicle recruitment, they have transitioned into a state of abnormally low follicle recruitment.
In conducting research on the FMR1 geneFMR1 gene , CHR described a sub-genotype of the gene, which does exactly that: women with the so-called het-norm/low sub-genotypes presents with a PCO-like ovarian phenotype at young ages, when they recruit a large number of follicles into the egg maturation process. Then they are left with DOR because of excessive early recruitment of eggs. The het-norm/high FMR1 genotype, in turn, does exactly the opposite. Women with this sub-genotype recruit their immature eggs into maturation unusually slowly at young ages, and at very advanced ages (above age 42) still have unusually good ovarian reserveovarian reserve .
Last Updated: November 15, 2014