GynaecologyFree in the app
Ovulation induction, IUI and IVF
What to give and when to refer.
Source: NICE NG257 (2026) · PCOS guideline 2023LetrozoleFirst line in PCOS2.5 mg days 2–6; increase to 5 then 7.5 mg if no follicle.⚠ Off-label in the UK.
ClomifeneOvulation induction50 mg days 2–6; increase to 100 then 150 mg.⚠ Scan at least the first cycle; maximum 6 months.
- Confirm ovulation: mid-luteal progesterone above 30 nmol/L.
- Clomifene-resistant: ovarian drilling, add metformin, or gonadotrophins.
- IUI: unexplained, mild endometriosis or mild male factor after 2 years — up to 4 stimulated cycles, or IVF.
- IVF (NICE 2026): under 40 — 3 full cycles plus up to 3 more considered; 40–41 — 1 cycle.
- IVF steps: stimulation (antagonist protocol), trigger, egg collection 34–36 h later, IVF or ICSI, day-5 single embryo transfer, progesterone support.
A summary for trained clinicians. Always check the full guideline, the patient in front of you and your hospital's protocol. Spotted an error? Tell us.