PCOS and Myo-Inositol: What Else Should You Know?
Dr. Norbert Gleicher
5/19/2025
A few words about the Polycystic Ovary Syndrome (PCOS), by many considered to be the most frequent cause of female infertility, and involving at least 10% of all women. Before reading this blog you should start by reading our blog post about our thoughts on myo-inositol and PCOS.
Let’s start with the fact that PCOS is not a disease but – as the name already points out – a syndrome. That means that PCOS is not a single medical condition, but a basket of conditions thrown together under one name because of several common denominators. How many such conditions – called phenotypes – exist is getting increasingly controversial. Most fertility specialists still believe that PCOS is made up of 4 such phenotypes, A, B, C, and D; others believe only the first three represent PCOS, and an increasing number of investigators, including those at New York’s Center for Human Reproduction (CHR) and Mount Sinai’s Medical Endocrinology Department, believe that PCOS has only 2 genomically distinct sub-types, a first more-less what in general are considered the A, B, and C phenotypes and – separately – the old D phenotype, which in the medical literature is widely misunderstood and – even by fertility specialists - frequently overlooked.
This phenotype is also the PCOS patient who under no circumstances should receive Myo-Inositol or, for that matter, any other Inositol supplementation because – especially after approximately age 35, women with this phenotype become hypo-androgenic (i.e., their androgen levels – also called male hormones - become abnormally low). Because ovaries require good androgen levels to produce eggs in good numbers and good quality, women with this phenotype after age 35 frequently become infertile, while, indeed, having been fertile up to that point.
Interestingly, like all PCOS patients, these D-phenotype women also started out with abnormally high androgens at young ages after their first menstrual period. This fact, indeed, is likely he principal reason why all these patients are thrown together under the name PCOS.
In contrast to all other PCOS patients, the D-phenotype, however, does not maintain abnormally high androgens into advanced ages, but starts dropping androgens progressively from the 20s on. By ca. age 25, they enter the normal androgen range in which they remain for ca. 10 years, until after roughly age 35 coming out of the normal range into, as noted above, abnormally low range, leading to infertility.
At that point, these women require even with in vitro fertilization (IVF) androgen supplementation if they are to conceive. The CHR in such cases recommends androgen supplementation with DHEA until testosterone levels are back into norma range, which usually takes at least ca. 4-6 weeks. The CHR then, however, still continues to monitor androgen levels every few months to make sure they remain in normal range. Both too high and too low testosterone levels are harmful to pregnancy chances, whether in achieving spontaneous pregnancies or in achieving pregnancies through fertility treatments.
One more word about why D-phenotype women so frequently are, even by fertility doctors, overlooked in their diagnosis. The reasons are simple to understand: They don’t look like “typical” PCOS patients and don’t behave like them medically either. A large majority of PCOS patients are obese (usually demonstrating truncal obesity), have hirsutism (excessive facial hair), often acne, and are anovulatory and, therefore, have very irregular periods. D-phenotype women have none of these phenotypical stigmata: they have lean BMIs (therefore, this phenotype is also called the “lean” phenotype), have regular menses and, at least between ages 25-35 have usually regular periods, have neither excessive hair growth nor acne. In short, since they don’t look and behave like a majority of PCOS patients, they are mostly never diagnosed.
If you need help managing your PCO S, schedule a consult with us today!
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