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Polycystic Ovary Syndrome (PCOS)

The most common endocrine disorder in women of reproductive age, affecting an estimated 10 to 13% of women; up to 70% of cases go undiagnosed1. Symptoms often improve substantially when the metabolic drivers are addressed, though PCOS is a long-term condition rather than something that resolves permanently.

Hormonal & Women's Health Evidence-Based

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Definition

What Is PCOS?

PCOS is a complex endocrine and metabolic disorder. Despite the name, it is not a cyst disease: the small follicles seen on ultrasound are immature follicles that failed to ovulate.

Clinically, PCOS is defined by the Rotterdam criteria, which require two of three features: irregular or absent ovulation, clinical or biochemical hyperandrogenism (acne, hirsutism, alopecia or elevated androgens on labs), and polycystic-appearing ovaries on ultrasound. It affects an estimated 10 to 13% of women of reproductive age worldwide1, making it the most common endocrine disorder in this group. Insulin resistance is common, including in lean women, and is a major driver of hyperandrogenism, weight gain and long-term cardiometabolic risk.

There are four distinct Rotterdam phenotypes based on which combination of features is present. Each phenotype presents differently and benefits from a tailored treatment focus (see below):

Polycystic ovary syndrome, ovaries with many small follicles beside the uterus, with a magnified view

Phenotype A, Classic PCOS (often the most common)

All three Rotterdam features present, hyperandrogenism + oligo/​anovulation + polycystic ovaries. Strongest association with insulin resistance, central weight gain and long-term metabolic risk. Responds best to insulin-sensitizing strategies.

  • โ†’Hallmarks: Irregular periods, acne, hirsutism, central weight gain, often acanthosis nigricans
  • โ†’Primary lever: Insulin resistance, addressed with low-glycemic eating, strength training, inositol
  • โ†’Labs: Raised free testosterone, low SHBG, raised AMH; glucose and insulin tests may show insulin resistance

Phenotype B, Non-PCO PCOS

Hyperandrogenism + oligo/​anovulation, but ovaries appear normal on ultrasound. Often misdiagnosed because the ultrasound is "clean." Symptom picture and metabolic risk are similar to Phenotype A.

  • โ†’Hallmarks: Same as classic PCOS minus the polycystic ovaries
  • โ†’Watch-out: Easily missed by ultrasound-only diagnosis; ask whether androgen blood tests are needed
  • โ†’Labs: Elevated free T, normal AMH, normal ovarian morphology

Phenotype C, Ovulatory PCOS

Hyperandrogenism + polycystic ovaries, but periods are regular. Often confused with "just hormonal acne" or persistent PMS. Insulin resistance is still present in many cases.

  • โ†’Hallmarks: Regular cycles with persistent acne, hirsutism or hair thinning
  • โ†’Primary lever: Lowering androgens, for example with spearmint tea, inositol or zinc
  • โ†’Labs: Elevated free T or DHEA-S, regular ovulation confirmed (day 21 progesterone)

Phenotype D, Non-Hyperandrogenic PCOS

Oligo/​anovulation + polycystic ovaries, with no clinical or lab hyperandrogenism. Often presents in thinner women. Lowest metabolic risk profile, but real fertility impact.

  • โ†’Hallmarks: Irregular cycles, anovulation, no acne or hair changes
  • โ†’Primary lever: Restoring ovulation, after thyroid disease and raised prolactin are ruled out
  • โ†’Labs: Normal androgens, elevated AMH, sometimes elevated LH:FSH ratio
By the Numbers

PCOS by the Numbers

1 in 10
women of reproductive age worldwide have PCOS1
Up to 70%
of affected women worldwide remain undiagnosed1
~1 in 2
have insulin resistance, in lean women too, not only with higher body weight23
4ร—
the odds of type 2 diabetes, also in weight-matched studies (35-⁠study meta-analysis)4
2 to 3ร—
the odds of endometrial cancer in a meta-analysis, higher in women under 54; the absolute risk stays low5
1 in 3
women waited more than 2 years for a diagnosis, and nearly half saw 3 or more health professionals (survey of 1,385 women)6
Signs & Symptoms

Symptoms of PCOS

PCOS rarely shows up as a single symptom.

SymptomWhat happens
Reproductive & Hormonal Symptoms
Irregular or Absent Periods (Oligo/​Amenorrhea)Cycles longer than 35 days, fewer than 8 periods a year or none at all, because the ovaries are not releasing an egg consistently.
Hormonal Acne (Jawline, Chin, Chest)Persistent inflammatory acne along the jawline, chin, lower cheeks, chest or upper back, driven by raised androgens.
Hirsutism (Excess Facial and Body Hair)Coarse, dark hair on the upper lip, chin, chest, abdomen and inner thighs, from androgens acting on hair follicles.
Scalp Hair Thinning (Androgenic Alopecia)Diffuse thinning at the crown and a widening part; the same androgens that grow hair on the chin shrink the follicles on the scalp.
Infertility / Anovulatory CyclesPCOS is the most common cause of anovulation and a leading cause of infertility1; without consistent ovulation, conception is less likely.
Heavy Bleeding & Recurrent MiscarriageAfter months without ovulation, the thickened uterine lining can shed as a heavy, prolonged or clot-filled bleed. PCOS is also linked to a higher miscarriage risk, which is worth discussing with your clinician if you are trying to conceive.
Metabolic, Systemic & Skin Symptoms
Weight Gain (Central / Visceral)Weight gain around the midsection that is harder to lose, partly because insulin resistance favors fat storage. Harder is not impossible: diet and activity remain first-line in international guidelines.
Acanthosis Nigricans & Skin TagsVelvety dark patches on the neck, armpits or skin folds, often with skin tags; both are skin signs of high insulin levels.
Severe Fatigue & Post-Meal Energy CrashesHeavy tiredness and poor focus after carbohydrate-heavy meals, reflecting swings in blood sugar and insulin.
Intense Carbohydrate Cravings & "Hangry" Mood SwingsUrgent cravings for sugar and fast carbohydrates between meals, often with irritability or shakiness if a meal is delayed.
Anxiety & DepressionDepression and anxiety are much more common in PCOS, and international guidelines advise screening every woman with PCOS for both7.
Sleep Apnea & Poor Sleep QualityObstructive sleep apnea is more common in PCOS, independent of weight. Snoring with unrefreshing sleep or daytime sleepiness warrants a sleep assessment7.
โš ๏ธ Pattern to watch for: Skin (acne + hirsutism + acanthosis nigricans) + cycle (irregular or missing) + energy (crashes + cravings) is a pattern worth taking to a clinician. It is not a diagnosis: thyroid disease and raised prolactin, both covered in the tests below, can produce a similar picture, which is why the workup exists.
Causes

Causes of PCOS

The exact cause of PCOS is unknown1. It arises from inherited tendencies interacting with metabolic and environmental factors, and the mix differs from one woman to the next2.

CauseHow It Contributes to PCOSWhat Helps
Genetic predispositionPCOS runs in families: in a twin study of more than 3,000 women, identical twins were about twice as alike as non-identical sisters8. A family history of PCOS or type 2 diabetes raises risk1.Genes cannot be changed, but the same eating and activity measures apply, and glucose testing at diagnosis and every 1 to 3 years (conventional care) catches diabetes early7
Ovarian androgen overproductionIn most women with PCOS the ovary itself makes too much androgen: cells from polycystic ovaries overproduce steroid hormones even when grown in the laboratory2. The raised androgens drive acne, excess hair and irregular ovulation.Spearmint tea, which lowered free testosterone in a trial9 (Supplement Protocol); a combined birth control pill or, with reliable contraception, an anti-androgen (conventional care)
Insulin resistance and high insulinAbout half of women with PCOS have insulin resistance, and the extra insulin the body makes to compensate acts on the ovary and worsens androgen excess2. It occurs independently of weight, though some lean women have normal insulin sensitivity3.Low-glycemic, protein-anchored meals and a short walk after eating (Nutritional Strategy); inositol or berberine, with limited evidence (Supplement Protocol); insulin-sensitizing medication (conventional care)
Excess body weightWeight gained over the course of life is a major factor2, and higher weight worsens how PCOS presents10. PCOS also occurs in women of every size.Diet and physical activity, which in trials modestly lowered weight and the free androgen index (Nutritional Strategy); weight-inclusive care is an equally valid choice
Conditions before birthResearch points to androgen exposure in the womb and poor fetal growth as early influences, alongside genes2.Nothing to change now; the same eating and activity measures apply
Diagnosis

How PCOS Is Diagnosed

Diagnosis needs two of the three Rotterdam features, after conditions that mimic PCOS are ruled out.

TestWhat it shows
At-Home Screening
These are not diagnostic on their own, but strong patterns can guide your next steps before investing in formal testing:
Cycle Length & Regularity TrackingTrack 3 to 6 cycles. Cycles longer than 35 days, fewer than 8 a year, or no period for 3 months or more in someone previously regular is the strongest screening signal. Adolescents are judged against age-based thresholds.
Basal Body Temperature (BBT) ChartingSeveral months of flat charts, without the 0.4 to 1.0ยฐF (0.2 to 0.6ยฐC) rise after ovulation, suggest anovulation, which has several possible causes including PCOS.
The PCOS Symptom ChecklistCount the symptoms above that apply, plus a family history of PCOS or type 2 diabetes. This is an informal checklist, not a validated score; if several apply, raise them with your doctor, who can decide which tests are needed.
Lab & Clinical Tests
Reproductive Hormone Panel (Day 2 to 5 of cycle)Total and free testosterone, SHBG (often low), DHEA-S, androstenedione, LH and FSH, progesterone (day 21 to confirm ovulation) and AMH (often elevated in PCOS).
Metabolic / Insulin PanelFasting glucose, HbA1c and, most accurately, a 75 g oral glucose tolerance test; insulin tests are of limited use in routine care7. Also a fasting lipid panel.
Thyroid & PituitaryTSH, free T4, free T3, TPO antibodies and prolactin. Hypothyroidism and hyperprolactinemia can mimic PCOS by causing anovulation.
Adrenal / Rule-Out Panel17-⁠OH progesterone (rules out non-classical congenital adrenal hyperplasia, known as CAH; draw morning, day 2 to 5), 24-⁠hour urinary cortisol or a late-night saliva cortisol test if Cushing's syndrome is suspected11. Important to rule these out before committing to a PCOS treatment plan.
Nutrient & Inflammation StatusVitamin D where deficiency is suspected, ferritin (often low with heavy bleeds) and B12, to find deficiencies worth correcting in their own right.
Transvaginal Pelvic UltrasoundLooks for follicle count and ovarian volume, ideally early in the cycle (day 3 to 5). Twenty or more follicles per ovary, or ovarian volume greater than 10 mL, meets criteria. Not required in adolescents within 8 years of menarche, because polycystic-appearing ovaries are common and benign in that window.
Treatment Comparison

Conventional and Holistic Treatment for PCOS

๐ŸŒฟ HOLISTIC
๐Ÿ’Š CONVENTIONAL
๐ŸŒฟ

Holistic / Functional Approach

Work on insulin resistance and weight through food and activity, alongside medical care

Primary Treatment
Low-glycemic whole-food nutrition + strength training + targeted supplements (inositol, berberine, vitamin D)
Duration
3 to 6 months for early improvement; 6 to 12 months to judge the effect on cycles
Effect on Underlying Disorder
Improves insulin resistance and symptoms for many; PCOS is long-term, so the changes need to be kept up
Fertility Outcome
Not yet measured: lifestyle trials have not reported cycle regularity or live birth10

Full Holistic Approach Includes

  • Low-glycemic, anti-inflammatory whole-food eating, protein at every meal, half the plate non-starchy vegetables
  • Strength training 2 to 4x per week, plus daily walking, both effective insulin sensitizers
  • Inositol (myo + D-chiro 40:1, 4 g per day), vitamin D3, omega-⁠3 and magnesium; berberine only as the one Tier 2 addition for a specific problem (see the supplement tiers)
  • Sleep optimization, 7 to 9 hours, screen for sleep apnea
  • Stress care: breathwork, daylight exposure, no late caffeine
  • Gut health, fiber, fermented foods
  • Endocrine-disruptor reduction: replace plastic, fragranced cosmetics, conventional cleaning products
  • Cycle tracking, identify ovulation and progesterone-phase return as treatment progresses
โš ๏ธ Side effects: Mild blood-sugar fluctuations the first 2 weeks as insulin sensitivity improves; occasional GI changes from berberine; body shape may change before the scale moves, as muscle replaces visceral fat.
Supplement Protocol

Evidence-Based Supplements for PCOS

Supplements are accelerators, not replacements for nutrition and lifestyle. This is a menu to choose from, not a protocol to take all at once. Most people should take no more than a few, picked by what they are actually trying to change. The tiers below run from best-evidenced to least, and the cost of working down the whole list is substantial for benefit that gets thinner as you go.

Supplement What it is for Typical range Timing Notes & cautions
Tier 1, start here: inositol (the best-studied supplement for PCOS), vitamin D (for a common deficiency) and two widely used options whose benefits in PCOS are less certain, as their rows say. Most people need nothing beyond this tier.
Myo-inositol + D-chiro-inositol (40:1)The best-studied supplement for PCOS, though "best-studied" is not the same as proven. The systematic review informing the 2023 International Evidence-based Guideline for PCOS concluded that the evidence is limited and inconclusive overall, while finding benefit signals for some metabolic measures and, for D-chiro-inositol, for ovulation. Reasonable to try with realistic expectations.124 g myo + 100 mg D-chiro per daySplit, half AM and half PM, with or without food3 to 6 months for full effect. Maintain the 40:1 ratio: higher D-chiro doses can hurt ovulation.
Vitamin D3 (with K2)Regulates insulin signaling, AMH and follicular maturation. One review reports that 67 to 85% of women with PCOS have vitamin D levels below 20 ng/mL13. There is some, but limited, evidence that correcting it helps cycle regularity and insulin resistance13.D3: set the dose with your clinician; most adults need no blood test first; K2 (MK-⁠7): 100 to 200 mcg per dayWith a fat-containing meal, morning preferredSevere deficiency is sometimes corrected with higher short-term doses, but that is a clinical decision, not a self-directed one. Dosing limits: the adult tolerable upper intake level is 4,000 IU/day. The Endocrine Society's 2024 guideline found no clear evidence for an optimal target level; the National Academies (formerly the Institute of Medicine) set sufficiency at 20 ng/mL (50 nmol/L). Any dose above 4,000 IU/day needs a blood test and a clinician, not a self-directed dose. If you take a blood thinner, clear any vitamin K supplement with the clinician managing it before you start or stop: vitamin K interferes with some anticoagulant medicines, and changing your intake can destabilize your monitoring results. Keeping intake consistent matters more than avoiding it. Not all blood thinners are affected the same way, which is why this is a conversation with your prescriber.
Omega-⁠3 EPA/DHALowers triglycerides, which are often raised in PCOS; effects on insulin sensitivity, inflammation and mood are not established.2 g combined EPA+DHA per dayWith mealsChoose a third-party-tested product for purity. Cod liver oil is high in vitamin A; avoid it if you are pregnant or trying to conceive. In heart trials, fish oil supplements raised the risk of atrial fibrillation, an irregular heartbeat, more so above 1 g a day14, so check this dose with your clinician first. At higher doses fish oil can increase bleeding risk; tell your clinician if you take a blood thinner or have heavy bleeding.
Magnesium GlycinateRequired for insulin signaling, progesterone production, GABA synthesis and sleep. Whether supplements improve insulin resistance in PCOS is not established.300 to 400 mg elemental magnesium per dayEvening, 30 to 60 min before bedIn pregnancy, check the dose with your midwife or doctor. Magnesium oxide is poorly absorbed. The top of this range is above the 350 mg/day upper intake level for supplemental magnesium; above that, diarrhea is common. With kidney disease, take it only on your clinician's advice.
Tier 2, add ONE for a specific problem. Chosen by what you are trying to change, not taken together.
BerberineA plant alkaloid that activates AMPK, the cellular energy sensor also targeted by common insulin-sensitizing medication. Trials report lower fasting insulin and improved insulin sensitivity in PCOS, though they are mostly small. Berberine interacts with many prescription medicines through CYP3A4 and P-glycoprotein, so check with your prescriber before starting it.15500 mg 2 to 3x per day (1,000 to 1,500 mg/day total)With mealsCan lower blood sugar; monitor it if you have diabetes. Do not combine with cholesterol-lowering or immunosuppressant medication without supervision. Do not take it if you are pregnant or breastfeeding, and stop it when you start trying to conceive, as berberine can harm a newborn16.
N-Acetylcysteine (NAC)Increases glutathione, an antioxidant. Has been studied in small randomized trials for restoring ovulation in PCOS18; the evidence is limited.1,200 to 1,800 mg per dayEmpty stomach, 30 min before food, split twice dailyOne of the few supplements with randomized trial data for fertility in PCOS.
Spearmint TeaIn a randomized trial, spearmint tea lowered free testosterone in women with PCOS9. Modest but real.2 cups (each from ~1 g dried leaf) per dayDaily, any timeUse loose-leaf or single-ingredient teabags. Effect builds over 30+ days.
ZincModulates testosterone metabolism, reduces 5-⁠alpha-reductase activity (the enzyme that converts testosterone to DHT), supports skin healing and improves insulin signaling.15 to 30 mg per dayWith meals (food prevents nausea)If using long-term (greater than 8 weeks at higher doses), add 1 to 2 mg copper to prevent imbalance.
Coenzyme Q10 (Ubiquinol)Mitochondrial fuel for the developing egg and the energy demands of ovulation. Small trials suggest benefits for IVF outcomes in some groups; the evidence is limited.100 to 300 mg ubiquinol per dayWith a fat-containing meal, morning preferredCombine with omega-⁠3.
B-ComplexSupports methylation, neurotransmitter balance and homocysteine metabolism. Folate matters for anyone who could become pregnant.1 capsule per day per product labelMorning with foodIf trying to conceive, take 400 to 800 mcg folic acid a day, the form proven to prevent neural tube defects.
What to Expect

What to Expect Over Time

PCOS is long-term, so treatment and supportive care run together, with metabolic checks early and slower changes in skin and hair.

Treatment and supportive care, together
First Weeks

The diagnosis is confirmed and look-alike conditions ruled out. International guidelines advise checking glucose status at diagnosis, blood pressure, mood and sleep7. Eating and activity changes start here, alongside any medication.

Months 1 to 3

In trials, diet and exercise modestly lowered weight and the free androgen index, though the evidence is low quality10. Inositol, if used, is judged over 3 to 6 months.

Months 3 to 12

Excess hair responds slowly; guidelines allow at least 6 months of the pill or cosmetic treatment before adding an anti-androgen, which needs reliable contraception7. The pill can regulate cycles1; trials have not yet measured whether lifestyle change alone does.

Long Term

PCOS persists beyond the reproductive years1. Glucose is rechecked every 1 to 3 years and blood pressure yearly7. If periods stay infrequent, ask about protecting the uterine lining. Plan pregnancy with your clinician, because pregnancy risks are higher1.

When to Seek Care

See a clinician promptly for new, severe or rapidly worsening excess hair or acne, which needs tests to rule out a hormone-producing tumor7, or for prolonged bleeding or long gaps between periods1. Get a same-day appointment for heavy bleeding, soaking a pad or tampon every hour for more than 2 hours; call 911 if it comes with dizziness, fainting, chest pain or breathlessness. For low mood with thoughts of self-harm or suicide, call or text 988, or call 911 if you are in immediate danger.

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Next Steps

PCOS Responds to Metabolic Care

Symptoms often improve substantially when the metabolic drivers are addressed, though PCOS is a long-term condition rather than something that resolves permanently. Eating and activity changes start alongside any medication. Plan pregnancy with your clinician, because pregnancy risks are higher.

Explore Diabetes โ†’ Explore Ovarian Cysts โ†’

References & Evidence Notes

Each numbered entry below is either a source you can follow or a note setting out what the evidence does and does not support. Both are numbered together so the markers in the text line up.

Last reviewed October 20, 2026. Supplement entries are cross-checked against the NIH National Center for Complementary and Integrative Health and the Linus Pauling Institute Micronutrient Information Center.17 The diagnostic framework and treatment hierarchy on this page follow the 2023 International Evidence-based Guideline for PCOS.7 This page is nutrition education, not medical advice, and it does not replace your doctor. Two cautions about supplements not listed on this page. If you are pregnant, trying to conceive or could become pregnant, do not take saw palmetto. If you take hormonal contraception, discuss vitex and saw palmetto with your prescriber before starting either. This page lists many supplements; that is a menu to discuss, not a protocol to take all at once.

  1. World Health Organization. Polycystic ovary syndrome fact sheet. who.int. An estimated 10 to 13% of women are affected, and up to 70% are undiagnosed. ↩
  2. On what drives PCOS: in a review of the evidence, about two-thirds of women with PCOS had a typical pattern of ovarian androgen overproduction, insulin resistance occurred in about half and worsened androgen excess, and PCOS appeared to arise from genes interacting with factors such as prenatal androgen exposure and weight gained after birth, PubMed 27459230. ↩
  3. On insulin resistance in PCOS: a review found marked insulin resistance independent of obesity, with insulin acting on the ovary to modulate hormone production, while some groups of lean women with PCOS had normal insulin sensitivity, PubMed 23065822. ↩
  4. On PCOS and type 2 diabetes: a meta-analysis of 35 studies found women with PCOS had higher odds of type 2 diabetes, odds ratio 4.43, and 4.00 in studies matched for body mass index; these are mostly prevalence studies, and incidence data were scarce, PubMed 20159883. ↩
  5. On PCOS and endometrial cancer: a meta-analysis of 5 studies found higher odds of endometrial cancer in women with PCOS, odds ratio 2.79, and 4.05 when women over 54 were excluded; the authors caution that the evidence is far from robust and that the absolute risk is low because the cancer is uncommon, PubMed 24688118. ↩
  6. On delays in diagnosis: in an international online survey of 1,385 women with PCOS recruited through support groups, 33.6% reported more than 2 years and 47.1% reported seeing 3 or more health professionals before diagnosis, and few were satisfied with the experience, PubMed 27906550. ↩
  7. International Evidence-based Guideline for the Assessment and Management of Polycystic Ovary Syndrome, 2023 update, which sets the diagnostic framework and treatment hierarchy referenced throughout this page. ↩
  8. On heritability: in a Dutch twin-family study of more than 3,000 women, PCOS resemblance in identical twins was about twice that in non-identical sisters, pointing to a large genetic contribution, PubMed 16219714. ↩
  9. Grant P. Spearmint herbal tea has significant anti-androgen effects in polycystic ovarian syndrome. A randomized controlled trial. Phytother Res. 2010;24(2):186-⁠188. PubMed 19585478. In 42 women with PCOS and excess hair given spearmint tea twice a day or a placebo tea for 30 days, free and total testosterone fell in the spearmint group and the women rated their own hair growth as improved, but a clinician-rated hair score did not change significantly over the short trial. ↩
  10. On lifestyle treatment: in a Cochrane review of 15 randomized trials with 498 women with PCOS, diet, exercise and behavioral programs may have lowered weight by about 1.7 kg and improved the free androgen index, on low-quality evidence, and no trial measured menstrual regularity or live birth, PubMed 30921477. ↩
  11. On testing for Cushing's syndrome: Endocrine Society guidance recommends starting with one accurate test, such as urine cortisol or late-night salivary cortisol, and seeing an endocrinologist for a second test if a result is abnormal, PubMed 18334580. ↩
  12. Inositol for polycystic ovary syndrome: a systematic review and meta-analysis to inform the 2023 update of the International Evidence-based PCOS Guidelines. J Clin Endocrinol Metab. 2024;109(6):1630. Oxford Academic. Concluded the evidence is limited and inconclusive overall, with benefit signals for some metabolic measures and, for D-chiro-inositol, for ovulation. ↩
  13. On vitamin D in PCOS: a review reports that 67% to 85% of women with PCOS have 25-⁠hydroxyvitamin D below 20 ng/mL, and that there is some, but limited, evidence that supplementing helps menstrual problems and insulin resistance, with more randomized trials needed, PubMed 22574874. ↩
  14. Gencer B, Djousse L, Al-Ramady OT, Cook NR, Manson JE, Albert CM. Effect of long-term marine omega-⁠3 fatty acids supplementation on the risk of atrial fibrillation in randomized controlled trials of cardiovascular outcomes: a systematic review and meta-analysis. Circulation. 2021;144(25):1981-⁠1990. PubMed 34612056. Seven trials with 81,210 people followed for about 5 years: omega-⁠3 supplements were linked to a higher risk of atrial fibrillation (hazard ratio 1.25), more so in trials of more than 1 g a day (1.49), and the risk rose with each additional gram. ↩
  15. Berberine trials in PCOS report improved insulin sensitivity and lower fasting insulin, in mostly small studies; one found fasting insulin, fasting glucose and HOMA-IR all fell in the berberine group and not the control, while calling its own findings preliminary, PubMed 42255444. On interactions, see the NCCIH assessment, ref. 17. ↩
  16. On berberine in pregnancy and breastfeeding: the NIH National Center for Complementary and Integrative Health advises that women who are pregnant or breastfeeding should not use goldenseal, whose berberine can be harmful to newborns, NCCIH, goldenseal; and a laboratory study found berberine strongly displaces bilirubin from albumin and concluded that herbs high in berberine are best avoided in jaundiced newborns and in pregnancy, PubMed 8513024. ↩
  17. National Center for Complementary and Integrative Health (NIH), nccih.nih.gov, and the Linus Pauling Institute Micronutrient Information Center, lpi.oregonstate.edu/mic. ↩
  18. On N-acetylcysteine: a 2015 systematic review and meta-analysis in Obstetrics and Gynecology International (Thakker and colleagues) pooled 8 randomized trials in 910 women with PCOS and found higher ovulation and pregnancy rates with NAC than with placebo, and lower rates than with a standard prescription for PCOS; several trials were at high risk of bias and the authors call for better-designed trials, PubMed 25653680. ↩