Evidence‑Based Management of Polycystic Ovary Syndrome (PCOS)

Menstrual Cycle Regularization

Combined hormonal contraceptives (CHC) are the first‑line therapy for menstrual irregularities in women with PCOS because they suppress luteinizing‑hormone‑driven ovarian androgen production and raise sex‑hormone‑binding globulin, thereby reducing bioavailable androgens. 1
In clinical observations, CHC consistently produced regular 27–29‑day cycles, whereas levonorgestrel‑releasing IUDs yielded highly variable cycles (ranging from <2 weeks to >3 months). 1
No single CHC formulation is superior for PCOS; however, progestins with anti‑androgenic activity (e.g., drospirenone) may offer additional benefit. 1
Prior to initiating CHC, clinicians must screen for absolute contraindications such as prior thromboembolism, stroke, cardiovascular disease, migraine with aura, uncontrolled hypertension, smoking in women >35 years, and known thrombophilias. 1
If CHC are contraindicated, metformin is recommended as a second‑line option for improving menstrual cyclicity and ovulation rates in PCOS. 2

A fasting lipid panel should be obtained at the time of PCOS diagnosis and repeated periodically during hormonal therapy to monitor treatment‑related lipid changes. 3
Dyslipidemia affects up to 70 % of U.S. women with PCOS and is driven by visceral adiposity, insulin resistance, hyperandrogenism, and genetic factors, independent of overall obesity. 3
The typical PCOS lipid pattern is atherogenic, characterized by increased small dense LDL particles, reduced apoA‑1, and elevated lipoprotein(a), resembling the profile seen in diabetes and metabolic syndrome. 3
PCOS confers long‑term cardiovascular risk; metabolic syndrome is present in approximately 34–46 % of U.S. women with PCOS, contributing to elevated 10‑year ASCVD risk despite young age. 3
Borderline elevations in total cholesterol and LDL‑C are not absolute contraindications to CHC, but they warrant periodic lipid monitoring while on estrogen‑containing therapy. 3

In women with PCOS, a fasting glucose in the upper‑normal range and an HbA1c around 5.4 % indicate the absence of overt diabetes or impaired glucose tolerance. 2
Metformin is advised for PCOS patients who have type 2 diabetes or impaired glucose tolerance and have not achieved glycemic control with lifestyle measures alone. 2
Even without overt glucose intolerance, metformin is appropriate for overweight PCOS patients to improve insulin sensitivity and may further aid menstrual regularity when CHC are not used. 2

Caloric restriction combined with increased physical activity constitutes the foundational therapy for PCOS, producing measurable improvements in fasting glucose and insulin levels, though effects on hirsutism and fertility are modest. 2
Weight loss should be pursued before initiating pharmacologic agents for obesity; metformin is reserved for cases where lifestyle modification fails to achieve desired metabolic outcomes. 2

Spironolactone should be continued for acne and hyperandrogenic symptoms in PCOS because it provides effective androgen‑receptor blockade. 1
While on spironolactone, serum androgen concentrations become unreliable; clinicians should not use these values to guide treatment decisions. 1
Adding spironolactone to CHC is a common second‑line strategy for persistent hirsutism or acne. 1

Severe menstrual irregularity (including cycles >100 days) places women with PCOS at increased risk for endometrial hyperplasia and carcinoma due to prolonged unopposed estrogen exposure. 1
CHC confer endometrial protection by delivering regular progestin exposure and inducing scheduled withdrawal bleeding. 1

Repeat fasting lipid panel 3–6 months after starting CHC to detect possible triglyceride elevation and assess LDL‑C reduction. 5
If LDL‑C remains >100 mg/dL or cardiovascular risk factors worsen, consider initiating statin therapy, ensuring effective contraception due to teratogenic potential. 5
Lipid‑lowering agents should be used solely for cardiovascular risk reduction and not for treating hyperandrogenism or infertility. 5
Screen for impaired glucose tolerance or type 2 diabetes with an oral glucose tolerance test, and repeat every 3–5 years or sooner if risk factors evolve. 3
Evaluate additional cardiovascular risk factors (family history of premature disease, smoking status, hypertension, obstructive sleep apnea) at each visit. 3
Measure blood pressure and body‑mass index at every clinical encounter. 5

Do not attribute dyslipidemia in PCOS solely to obesity; lipid abnormalities often occur independent of body weight. 3
Do not postpone lipid screening or dismiss borderline elevations in young women (e.g., age 25); lipid abnormalities begin early in adulthood and tend to persist. 3
Do not rely on levonorgestrel‑releasing IUDs to regularize menstrual cycles in PCOS, as they generally fail to provide the necessary estrogen component. 1
Do not prescribe CHC to women with severe hypertriglyceridemia without close monitoring, given the risk of estrogen‑induced pancreatitis. 5
Do not use androgen levels to monitor treatment response while the patient is on spironolactone, as the drug suppresses measurable androgen concentrations. 1