A 28-year-old woman from Delhi presents to the infertility clinic with a 3-year history of primary infertility. Her husband's semen analysis is normal. Menstrual cycles are regular (28 days) but she reports anovulatory cycles on progesterone challenge test. Pelvic ultrasound shows normal ovaries with no follicular development. FSH and LH levels are normal (5 mIU/mL and 4 mIU/mL respectively), and prolactin is 12 ng/mL. Thyroid function tests are normal. She has a BMI of 24 kg/m². What is the most appropriate first-line ovulation induction agent for this patient?

Explanation

## Clinical Assessment This patient has **normogonadic anovulation** (normal FSH/LH, normal prolactin, regular cycles but anovulatory). The normal BMI excludes PCOS as a primary diagnosis, and the normal gonadotropins rule out hypogonadotropic hypogonadism. ## First-Line Ovulation Induction Strategy **Key Point:** Clomiphene citrate (CC) is the gold standard first-line agent for normogonadic anovulation with normal gonadotropin levels. ### Why Clomiphene Citrate? 1. **Mechanism**: Selective estrogen receptor modulator (SERM) that blocks negative feedback of estrogen on the hypothalamus and pituitary, increasing endogenous FSH secretion 2. **Cost-effective**: Oral agent, inexpensive, no need for monitoring ultrasounds in initial cycles 3. **Safety profile**: Minimal risk of ovarian hyperstimulation syndrome (OHSS) and multiple pregnancies 4. **Efficacy**: 70–80% ovulation rate in normogonadic anovulation; cumulative pregnancy rate ~40% over 6 cycles **High-Yield:** Standard dose is 50 mg daily for 5 days starting from day 3 of the cycle. If no ovulation, increase to 100 mg daily in the next cycle (max 150 mg/day). ## Why Other Options Are Not First-Line | Agent | Indication | Why Not First-Line Here | |-------|-----------|-------------------------| | Gonadotropins (FSH) | Clomiphene resistance, hypogonadotropic hypogonadism | Requires daily injections, frequent ultrasound monitoring, higher cost, increased OHSS risk | | Letrozole | PCOS, clomiphene resistance, elevated estradiol | Aromatase inhibitor; useful in PCOS but not standard first-line for normogonadic anovulation | | GnRH agonist | Hypogonadotropic hypogonadism, pulsatile therapy | Not indicated; patient has normal gonadotropins | **Clinical Pearl:** Before starting ovulation induction, always confirm anovulation with progesterone challenge test (as done here) and rule out other causes (thyroid, prolactin, PCOS). This patient's normal hormonal profile and regular cycles make CC the ideal starting point. ## Monitoring During Treatment - Basal body temperature chart or serum progesterone (day 21) to confirm ovulation - Pelvic ultrasound only if no ovulation after 2–3 cycles or if breakthrough bleeding occurs - Counsel on coitus timing (day 12–16 of cycle if ovulation occurs) **Warning:** Do not start gonadotropins or GnRH agonists without first trialing CC in normogonadic anovulation — this wastes resources and increases iatrogenic complications.