PCOS with anovulatory infertility — ovulation induction: letrozole vs clomiphene vs gonadotropins

2 Answers

This is an anovulatory infertility case in PCOS (Rotterdam criteria) with oligomenorrhea and elevated AMH. Based on current evidence, including the PCOSMIC trial, letrozole is the first-line ovulation induction agent, showing higher ovulation and live birth rates compared to clomiphene, with lower multiple pregnancy risk. Metformin is not first-line for ovulation induction but may be added in patients with insulin resistance, impaired glucose tolerance, or BMI ≥25–30, and in clomiphene/letrozole resistance. It can also be considered as an adjunct in metabolic optimization. If there is failure to ovulate or conceive after ~3–6 cycles of letrozole, the next step is gonadotropin therapy with low-dose step-up protocol and ultrasound monitoring. IVF referral is appropriate after failure of ovulation induction with gonadotropins, presence of additional infertility factors (e.g., tubal/male factor), or prolonged infertility duration (>2 years). Given high AMH (8 ng/mL), the patient is at increased risk of OHSS. Risk minimization includes: Prefer letrozole as first-line Use low-dose gonadotropin protocols with careful follicular monitoring Avoid multifollicular development (cycle cancellation if needed) In IVF cycles: consider GnRH antagonist protocol with GnRH agonist trigger and “freeze-all” strategy if high response Overall, initiate letrozole with lifestyle modification (weight optimization), add metformin selectively, and escalate stepwise while actively minimizing OHSS risk.

ok