What is myo-inositol 40:1, and how does it support hormone health?

Myo-inositol 40:1 refers to a specific ratio of two naturally occurring compounds, myo-inositol and D-chiro-inositol, studied for their role in supporting ovarian hormone signaling and menstrual cycle regularity.^† The 40:1 ratio reflects the natural balance of these two compounds found in the body, which is part of why it has become the most studied combination for hormone and cycle-related research.^†

Why the 40:1 ratio specifically

Research comparing different myo-inositol to D-chiro-inositol ratios found the 40:1 combination most effective at restoring ovulation among the ratios tested, according to a clinical trial published in the European Review for Medical and Pharmacological Sciences. A subsequent review published in Gynecological Endocrinology noted that the 40:1 ratio mirrors the naturally occurring plasma balance between the two compounds more closely than other combinations that have been tested.

"It's not a one-size-fits-all."

— Dr. Samantha Ess, ND, Naturopathic Doctor specializing in hormone health and fertility

What's in Myo Chiro 40:1

Myo Chiro 40:1, formulated to support cycle regularity, delivers 2000 mg of myo-inositol and 50 mg of D-chiro-inositol in that same clinically studied 40:1 ratio, formulated to support healthy hormone signaling, ovarian health, and menstrual cycle regularity.^† D-chiro-inositol specifically supports healthy androgen function and ovarian hormone function.^†

What "regular" actually means

A typical menstrual cycle ranges from 21 to 35 days, according to Mayo Clinic, and there is a fair amount of normal variation from cycle to cycle. Understanding your own baseline is a useful starting point before making changes to your routine.

"When people want to support their fertility or their wellness, it's not just about swallowing any pill and getting a result. You have to put in the work."

— Amy Suzanne Upchurch, Founder and CEO of Pink Stork

Safety and tolerability

Inositol has been generally well tolerated across clinical research, with mild gastrointestinal effects reported mainly at much higher doses than what is typically used in a 40:1 ratio formula, according to a safety review indexed on PubMed. Myo Chiro 40:1 is not recommended for use during pregnancy, and a provider consultation disclaimer applies if you are breastfeeding.^†

Always consult your healthcare provider before starting any new supplement, especially during pregnancy, breastfeeding, or while managing a medical condition.

Pairing with other fertility-focused products

Many women layer Myo Chiro 40:1 with our organic fertility tea with vitex and red raspberry leaf for a broader approach to cycle regularity and reproductive wellness while trying to conceive.^†

Trust in what you are taking

• Myo Chiro 40:1 is third-party tested and manufactured in cGMP-certified facilities.
• It uses the same clinically studied 40:1 ratio referenced across the research cited above.

Frequently asked questions

What's the difference between myo-inositol and D-chiro-inositol?

They are two related compounds naturally found in the body, studied together in specific ratios for their role in ovarian hormone signaling and metabolic function.

Why does the ratio matter so much?

Research comparing different ratios found that 40:1 most closely mirrors the body's natural plasma balance and outperformed other tested ratios for restoring ovulation in clinical research.

Is myo-inositol safe to take daily?

Clinical research has generally found inositol well tolerated, with mild gastrointestinal effects reported mainly at much higher doses than typical 40:1 formulas provide.

Can I take this while pregnant?

No. Myo Chiro 40:1 is not intended for use during pregnancy. Talk with your healthcare provider about your specific situation.

How long does it take to notice a difference in cycle regularity?

Clinical research on inositol ratios has generally studied outcomes over a period of three months or longer, so consistency matters more than immediate results.

† These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. Always consult your healthcare provider before starting any new supplement, especially during pregnancy, breastfeeding, or while managing a medical condition. Keep out of reach of children.