IVF and ART techniques: stimulation, trigger, transfer, luteal support, OHSS prevention and cumulative success

Also known as In vitro fertilisation · IVF · ART · Assisted reproductive technology · ICSI · Controlled ovarian stimulation · Ovarian hyperstimulation syndrome · Luteal phase support

Exam-exhaustive FRANZCOG fellowship topic on IVF and ART techniques: the controlled ovarian stimulation protocols (long agonist vs antagonist), the trigger decision (hCG vs GnRH agonist trigger and the OHSS risk window), freeze-all and the OHSS prevention bundle, embryo culture and transfer (day 3 vs day 5 blastocyst, fresh vs frozen), the luteal phase support (vaginal, oral, IM progesterone with doses), the live-birth rate by maternal age and cycle number, the OHSS severity grading, and the cumulative success after up to 6 cycles. Anchored to the Cochrane 2021/2022 reviews, the Malizia 2009 cumulative live-birth data, and the regional guidelines (NICE NG257, RANZCOG, ASRM, ESHRE, HFEA).

high18 referencesUpdated 28 July 202618 min readVerification in progress

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14 MCQs

One-line fellowship answer

IVF and ICSI are the two ART procedures — ICSI for severe male factor and surgically retrieved sperm, IVF otherwise. The cycle is built on three decisions: (1) stimulation protocol — the GnRH antagonist is now first-line for most (shorter, lower OHSS risk, allows agonist trigger) while the long GnRH agonist remains standard for some indications; (2) trigger — hCG 5000 to 10,000 IU in standard risk, GnRH agonist (leuprolide or triptorelin 0.2 mg) in OHSS risk; (3) fresh or frozen transfer — element of the OHSS prevention bundle (antagonist + agonist trigger + freeze-all + metformin in PCOS). Luteal support is vaginal progesterone (8% gel 90 mg, 180 mg total daily) — with similar ongoing pregnancy to oral dydrogesterone 40 mg total daily and IM progesterone 100 mg daily — started the day of egg collection and continued to 10 to 12 weeks gestation. Cumulative live birth is around 72% by 6 cycles (optimistic) but falls from 32% per fresh transfer under 35 to under 2% over 44; the age cliff is the single most important modifier of success.^[9]^[13]^[14]^[16]^[17]

It is 08:00 on the IVF unit. A 32-year-old woman with PCOS has produced 24 follicles on day 12 of an antagonist cycle, her oestradiol is 4800 pg/mL, and the lead follicles are 18 mm. The embryologist is on standby. The decision you make before going to theatre is the one that decides whether the cycle ends in a healthy singleton or a week in hospital with tense ascites. The same three questions will be on the exam: which protocol, which trigger, and which transfer. Get the trigger wrong in a high responder and you have caused OHSS; get the luteal support wrong after an agonist trigger and you have caused luteal phase failure; transfer the day a hydrosalpinx is found and you have wasted the cycle.^[1]^[9]^[16]

Overview and definition

IVF is the in vitro fertilisation of oocytes with sperm, with subsequent embryo culture and transfer to the uterus. ICSI is the microinjection of a single spermatozoon into each mature oocyte. Both are part of the broader category of assisted reproductive technology (ART) — treatments involving the in vitro handling of oocytes, sperm, or embryos; this includes IVF, ICSI, intrauterine insemination (IUI), gamete and embryo cryopreservation, and donor gametes. The clinic's modern bundle is built on three decisions — the protocol, the trigger, and the transfer — and the OHSS prevention bundle is the audit point for every high responder. Since the birth of Louise Brown in 1978, IVF has become the single most effective treatment for intractable infertility, with cumulative live-birth rates around 72% by 6 cycles in women under 35 (Malizia 2009).^[4]^[16]

The numbers that anchor every IVF counselling conversation

~46-51%Donor-oocyte pregnancy per transferfresh 51.3% / thawed 45.7% (ESHRE 2020)

72% (51%)Cumulative live birth, 6 cyclesoptimistic / conservative; 86%/65% under 35 (Malizia 2009)

~11% / ~8%Twin delivery, fresh vs FETESHRE 2020; eSET is the answer

OR 0.61OHSS, antagonist vs long agonist36 RCTs; LBR comparable (Cochrane 2016)

→ near 0%OHSS reduction, agonist triggercompared to hCG in antagonist cycles

21% vs 3%Multiple birth, ART vs naturalUS 2018 (CDC)

^[4] ^[5] ^[6] ^[1] ^[13]

References18Show

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