How should obese PCOS patients be managed before IVF?

[Partially verified — Tier B. The International PMOS Guideline covers lifestyle and weight management extensively; I have verified its fertility treatment recommendations directly but not the full weight-management chapter. Reviewer should confirm specifics against it.] What is well established and consistent across guidance: weight reduction in those with raised BMI improves ovulation, spontaneous conception, response to ovulation induction, and ART outcomes. The counselling difficulty is that this is frequently delivered as a precondition rather than as a recommendation, and BMI thresholds used as absolute barriers to treatment access are contentious. Two considerations should be weighed together: Time. Weight reduction is slow, and in a woman in her late thirties the delay may cost more in declining oocyte quality and quantity than the weight loss gains. A rigid BMI cut-off applied without regard to age can be harmful. Physiology. Insulin resistance with compensatory hyperinsulinaemia is present in 85% of those affected by PMOS/PCOS. Weight loss is physiologically harder in this group, and framing failure to achieve a target as non-adherence is both inaccurate and damaging to the therapeutic relationship. Practical measures with support: structured lifestyle intervention, addressing insulin resistance, and treating obstructive sleep apnoea where present. Anti-obesity pharmacotherapy and bariatric surgery are increasingly relevant but have specific implications for conception timing and micronutrient status that need managing. Reviewer: this answer deliberately quotes no BMI threshold. If your unit applies one, it should be stated here with its rationale and any age-based flexibility, rather than left implicit.