Inositol is one of my favorite supplements for fertility. It's a nutrient closely related to the B vitamins, and it's especially helpful for polycystic ovary syndrome (PCOS) because it helps regulate insulin levels.
Nearly one in ten women of childbearing age has PCOS, and it's one of the most common causes of fertility problems. PCOS is characterized by insulin resistance, a condition where the body doesn't respond appropriately to the hormone insulin.
Insulin resistance may lead to high insulin levels in the bloodstream, which could increase androgens. Many PCOS symptoms can be traced back to androgens, including hirsutism (unwanted hair growth), acne, irregular cycles, and anovulation (the absence of ovulation).
In this article:
- How to Increase Fertility Naturally with Inositol Supplements
- Polycystic Ovary Syndrome (PCOS) and Pregnancy
- Can I Take Inositol if I Don't Have PCOS?
- How Much Inositol Should You Take for Fertility Support?
- Can I Get Enough Inositol from Food to Help With Fertility?
- Frequently Asked Questions About Inositol for Fertility
- Key Takeaways
Inositol may help lower insulin, could improve egg health, and might even increase the chance of ovulation. In this article, I'll explain how inositol works, the different types of inositol, and why you may want to choose inositol for fertility support.
How to Increase Fertility Naturally with Inositol Supplements
To understand how to increase fertility naturally with inositol supplements, let's first examine what inositol is and what it does in your body.
Inositol is a sugar molecule naturally found throughout your body and in foods. There are nine types of inositol, and they exist in different ratios in your cells. Myo-inositol (MI) and D-chiro inositol (DCI) are two forms you'll see in supplements for fertility.
Of all the forms of inositol, MI is the most common in your body, especially in your brain, lungs, ovaries, and testes. DCI1 is the second most abundant and is usually found alongside MI. These two are primarily found in the body in a ratio of 40 to 1 MI to DCI.
Inositol makes up your cell membrane and is involved in many cellular processes, but its role in cellular signaling2, especially for insulin regulation and reproductive health, makes it especially helpful for PCOS and fertility.
Inositol is known as a second messenger3, which means it helps relay messages from hormones like insulin or even follicle stimulating hormone (FSH) from the outside to the inside of your cells. Essentially, inositol makes your cells more responsive to hormones or signals, which can positively impact the hormonal messages needed for fertility.
MI is necessary for fertility signaling4. To have a regular menstrual cycle, proper signaling from the hypothalamus–pituitary–gonadal5 (HPG) axis is required. Follicle stimulating hormone (FSH) and luteinizing hormone (LH) help promote the development of eggs in the ovaries, initiate the menstrual cycle, and trigger ovulation. MI is involved in the signaling pathway for both of these hormones.
In other words, MI is needed for the proper development of eggs and regular ovulation, two critical factors in fertility.
Polycystic Ovary Syndrome (PCOS) and Pregnancy
Since I recommend inositol primarily for my patients with PCOS, let's talk about PCOS and pregnancy. Getting pregnant with PCOS can be challenging for some people. In fact, PCOS is the most common cause of anovulatory infertility6.
Anovulatory infertility means you're not ovulating or not ovulating regularly. If you don't ovulate, you can't get pregnant because there's no egg to be fertilized.
PCOS is an endocrine disorder, which means it's a problem with your hormones. PCOS is characterized by excess androgen production, insulin resistance, and alterations7 in luteinizing hormone (LH), FSH, and estrogen. All of these hormones are needed in balance to become pregnant.
People with PCOS8 may not ovulate, and as a result, periods are irregular, or they don't have a period at all. Without ovulation, pregnancy can't occur.
High insulin levels might also impact fertility, and studies9 suggest that healthy glucose levels are needed to maintain a pregnancy. Since people with PCOS are more likely to be insulin resistant, this could make it harder to get pregnant and stay pregnant.
As a result, correcting blood sugar and lowering insulin becomes an essential part of a fertility protocol for PCOS.
I have a free meal plan and recipe guide to help support you in bringing in the nutrients that support your hormones and help balance your blood sugar.
Inositol Supplements for PCOS and Fertility
Okay, now you understand what inositol benefits do for fertility in general and why PCOS can make it harder to get pregnant. So, how do inositol supplements help with fertility?
Inositol supplements are used to support your body's natural levels.
In some cases, the body makes less inositol or can't convert MI to DCI, so supplementation could help restore the balance. For example, studies suggest low DCI levels may increase the risk of insulin resistance10, and people with PCOS may have lower DCI levels11. Insulin resistance for people with PCOS is also addressed with inositol.
One study12 found that women with PCOS who supplemented with DCI lowered insulin and androgens. But since the ratio of 40 to 1 MI to DCI is critical13 (and we will explore this more below), MI is also important for insulin sensitivity.
There are many studies on inositol supplements for PCOS for fertility, here are just some of the results:
- A study14 examining women with PCOS found that taking 100 mg of myo-inositol twice a day led to spontaneous ovulation (23 percent ovulation rate for those who took the supplement compared to 13 percent placebo).
- In another study15, women with PCOS who took high doses of MI (4000 mg) combined with folic acid noted significant improvements in ovulation rates.
Taking inositol (restored) the menstrual cycle for women with PCOS who took 2000mg MI and 200 mcg folic acid twice daily. In this small study16, 88 percent of the women (who previously did not have a period) had at least one menstrual cycle, and 72 percent maintained ovulation after the study was over. Even better? 40 percent of the people in the study became pregnant during the study.
These are just a few of the studies. The list of benefits of inositol for fertility, especially for PCOS, goes on and on. Inositol17 even appears to be as effective for promoting pregnancy as metformin, the medication usually prescribed to women with insulin resistance to normalize blood sugar.
A lot of factors go into fertility, so inositol alone may not be enough to get results. But if you’re addressing fertility issues, it’s an easy addition to your protocol that doesn’t come with much risk. Talk it over with your doctor and see what they think.
Can I Take Inositol if I Don't Have PCOS?
There isn't much research suggesting that taking inositol if you don't have PCOS will benefit fertility. If you have insulin resistance without PCOS, inositol may help. Otherwise, the research is lacking. Inositol won't hurt you, but if you don't have PCOS, it may not help with fertility.
The exception is for people undergoing in vitro fertilization (IVF). Adding MI as part of an IVF protocol may improve results, but more research is needed. Some studies show18 that women given MI had higher rates of retrievable eggs with a reduced need for treatment with FSH to stimulate egg production. A meta-analysis19 also concluded that MI helped induce ovulation for people undergoing IVF.
How Much Inositol Should You Take for Fertility Support?
Typical recommendations20 for myo-inositol supplementation for fertility are 2000 to 4000 mg daily with 100 mg of DCI daily. These amounts are designed to match the ratio in your body. They’re also the amount of each inositol you’ll find in our Myoinositol Plus, with additional nutrient and herb support with PCOS in mind.
Most of the research on inositol for fertility focuses on myo-inostiol. You want your supplement ratios to match physiological proportions in the body or about 40:1 MI to DCI. A study21 that used DCI for fertility found that the more DCI was given, the more egg quality went down.
The myo-inositol levels in the ovaries are higher than in other tissues. Taking too much d-chiro inositol could upset your natural ratios and impact your fertility.
It's always important to consult your healthcare practitioner since I don’t know your medical history and I can't give you medical advice. If you have any other medical conditions, it is essential to talk to your doctor about whether or not inositol is the right choice for you.
Can I Get Enough Inositol from Food to Help With Fertility?
Although inositol is found in some foods, getting enough inositol through diet alone is difficult if you need a therapeutic dose. A therapeutic dose means taking the amount of inositol that is effective in research studies, which is typically around 2000-4000 mg per day.
You can always eat inositol-rich foods to add more inositol to your diet. Here are some of the foods highest22 in inositol:
- Grapefruits
- Orange
- Cantaloupe
- Beans
- Brown rice
- Peanut butter
- Whole wheat
- Almonds
- Walnuts
- Organ meat
Frequently Asked Questions About Inositol for Fertility
How Much Inositol Should I Take for Fertility?
Most of the research on inositol for fertility uses 2000-4000 mg daily. This is typically divided into 2 doses, taken with breakfast and dinner. A ratio of myo-inositol to d-chiro inositol of 40 to 1 is usually recommended to match the proportions found in the body.
You’ll find this dose and ratio in carefully formulated inositol supplements like Myoinositol Plus.
Does Inositol Make You Ovulate?
Inositol has been shown to help induce ovulation in women with PCOS. Studies have found that inositol can help normalize ovulation and improve irregular cycles for people with PCOS.
Does Inositol Improve Egg Quality?
Inositol has been shown to improve egg quality in women with PCOS. One study23 found that taking inositol improved egg quality and resulted in more eggs being able to be fertilized.
Key Takeaways
- Inositol is a nutrient found in some foods and is also available as a supplement.
- Inositol is an effective supplement for supporting PCOS and improving fertility through its actions on insulin and reproductive hormone signals.
- The recommended dose of inositol for fertility is 2000-4000 mg daily.
- If you have other medical conditions, talk to your doctor about whether or not inositol is the right choice for you.
References
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- https://journals.lww.com/indjem/Fulltext/2016/20050/The_inositols_and_polycystic_ovary_syndrome.25.aspx ↩︎
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8227031/ ↩︎
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- https://journals.lww.com/indjem/Fulltext/2016/20050/The_inositols_and_polycystic_ovary_syndrome.25.aspx ↩︎
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- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3447676/ ↩︎
- https://www.semanticscholar.org/paper/Myo-inositol-content-of-common-foods%3A-development-a-Clements-Darnell/a4fe6e428501f09d5bf283459527b87dbf432aa3?p2df ↩︎
- https://pubmed.ncbi.nlm.nih.gov/21744744/ ↩︎