AlternativeOvitrelle / Pregnyl
Human chorionic gonadotropin (hCG)
Ovulation trigger / luteal support
LH-mimetic trigger — precipitates ovulation ~36 h post injection.
SC / IM
First-line for
- Ovulation trigger in IUI / IVF cycles
- Luteal support (declining use)
Mechanism
Binds LH receptor → resumes meiosis and triggers ovulation ~36 h later; supports corpus luteum.
"36 hours from hCG to egg"
- Time IUI / retrieval accordingly
- Beware OHSS potentiation
- Half-life ~24 h
Dosing
- Trigger
- 250 μg recombinant hCG SC single dose (or 5000–10000 IU urinary)
Contraindications
- AbsoluteHormone-dependent tumours, high OHSS risk (use GnRH agonist trigger instead)
Side effects
- Precipitates OHSS
- Injection reaction
Fetal & maternal notes
- • Not used in established pregnancy
Key interactions
GnRH agonists (trigger)
OKAlternative safer trigger in high-responders
Clinical pearls
- 💡 Cross-reacts with β-hCG assays for up to 10 days
- 💡 Freeze-all + agonist trigger cuts severe OHSS
Content last reviewed: REPLACE_ME (e.g. 2026-07)
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