A 28-year-old woman from Delhi presents with primary infertility of 3 years duration. She has regular menstrual cycles (28–30 days) with normal flow. Her husband's semen analysis is normal. On examination, she has a BMI of 32 kg/m², hirsutism on the face and chest, and acne. Pelvic ultrasound shows multiple small follicles arranged peripherally in both ovaries with increased ovarian stroma. FSH and LH levels are elevated with an LH:FSH ratio of 3:1. What is the most likely diagnosis?

Explanation

## Diagnosis: Polycystic Ovary Syndrome (PCOS) ### Clinical Presentation This patient meets the Rotterdam criteria for PCOS diagnosis, which requires 2 of 3 features: | Feature | Present in Case | |---------|------------------| | Oligo/anovulation or irregular cycles | Regular cycles (but may have anovulation) | | Hyperandrogenism (clinical or biochemical) | Hirsutism, acne ✓ | | Polycystic ovaries on ultrasound | Multiple follicles, increased stroma ✓ | ### Key Biochemical Findings **Key Point:** The elevated LH:FSH ratio (3:1 or higher) is a hallmark of PCOS. Normal ratio is 1:1 to 2:1. - **LH elevation** → increased androgen production from theca cells - **FSH relative deficiency** → arrested follicle development at 5–8 mm stage - Result: anovulation and infertility ### Pathophysiology ```mermaid flowchart TD A[Insulin resistance / Hyperinsulinemia]:::outcome --> B[Increased ovarian androgen production]:::outcome B --> C[FSH suppression]:::outcome C --> D[Arrested follicle development]:::outcome D --> E[Anovulation & Infertility]:::urgent A --> F[Increased LH pulsatility]:::outcome F --> G[LH:FSH ratio elevation]:::outcome ``` ### Associated Features **High-Yield:** PCOS is the most common endocrine disorder in women of reproductive age (5–10% prevalence). - Obesity (30–40% of cases) - Metabolic syndrome - Increased risk of type 2 diabetes - Dyslipidemia - Increased cardiovascular risk ### Management Overview 1. **Lifestyle modification:** Weight loss (5–10%) improves ovulation rates 2. **Ovulation induction:** Clomiphene citrate (first-line), letrozole, or gonadotropins 3. **Metabolic management:** Metformin for insulin resistance 4. **Hyperandrogenism:** Oral contraceptives or spironolactone if not pursuing pregnancy **Clinical Pearl:** Even with regular cycles, PCOS patients may have anovulatory cycles due to inadequate luteal phase progesterone. Progesterone challenge test or luteal phase progesterone level confirms ovulation. [cite:DC Dutta's Textbook of Obstetrics 8e Ch 11]