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REI#rei#ivf#primerPGY 2/3/4

IVF Basics Primer

Baseline visit, monitoring, trigger options (hCG vs Lupron), stimulation meds, surge prevention strategies.

Source: REI PGY-2 handoff (Matt Rohn primer)

Baseline visit:

  • Ultrasound: antral follicle count (AFC) — estimate of follicles you hope to stimulate. Evaluate for cysts or follicles that may interfere with stimulation.
  • Lab — Estradiol (E2): ensure no E2-producing follicles that may interfere with stimulation.

Monitoring visits:

  • Ultrasound: count follicles and measure size. Goal: as many follicles ≥ 14 mm (ideally 18–20 mm) but <24 mm.
  • Lab — Estradiol (E2): goal: E2 should double over 2 days. Mature follicles make ~200–400 pg/mL.

Trigger — stimulates / induces LH surge to trigger ovulation, resumption of meiosis.

  • hCG (Ovidrel or Pregnyl) — indications: low concern for OHSS; Lupron trigger not an option; hypothalamic or pituitary dysfunction (wouldn’t respond to Lupron trigger).
  • Lupron — stimulates endogenous LH release → ovulation. Needs an intact HPO axis. Indications: concern for OHSS (high E2, many follicles).

Timeline after trigger:

  • Lupron labs 12 hr after trigger (to ensure response): LH >20, progesterone >4. If no response → consider hCG trigger (cancel if high risk for OHSS).
  • Transvaginal oocyte retrieval (TVOR) 36 hr after trigger.

Stimulation meds (stimulate follicles to grow). Choose initial dose based on age, AMH, AFC; titrate based on response:

  • FSH — Gonal or Follistim.
  • FSH/LH combo (hMG) — Menopur.

Surge prevention — prevents premature endogenous LH surge so you can continue stimulating follicles without losing them to ovulation before retrieval:

  • GnRH antagonist — competitively binds to GnRH receptor in pituitary.
  • Provera — negative feedback on hypothalamus to decrease GnRH pulse frequency.
  • Lupron “flare” — short-term: release of gonadotropins (may give follicles an initial “boost”). Long-term: downregulation of GnRH receptor.

Referenced by handoffs