Restoring Insulin Sensitivity and Ovarian Function
Insulin resistance plays a central pathophysiological role in a substantial subset of women with polycystic ovary syndrome (PCOS), driving hyperandrogenism and arresting normal follicular development. Myo-inositol (MI) and D-chiro-inositol (DCI) act as second messengers for insulin signaling, helping to overcome cellular resistance.
Clinical literature consistently shows that administration of MI and DCI restores ovulatory function, reduces fasting insulin, and significantly decreases free circulating testosterone levels. Furthermore, compared to traditional insulin sensitizers like metformin, myo-inositol demonstrates a markedly superior gastrointestinal safety and tolerability profile.
The 40:1 Ratio and Assisted Reproduction
The physiological plasma ratio of MI to DCI in healthy women is approximately 40:1, a balance that is frequently disrupted in patients with PCOS due to altered epimerase activity in tissues. Restoring this precise ratio via exogenous supplementation has become standard clinical practice.
Within assisted reproductive technology (ART) protocols, inositol supplementation is associated with improvements in oocyte maturation and embryo quality. However, despite improvements in surrogate markers and ovarian response, high-quality randomized controlled trials confirming a direct translation to increased live birth rates remain scarce and contested.