IVF Protocols Overview — Individualised Stimulation Design

IVF stimulation protocols are not one-size-fits-all. Choice of protocol depends on age, AMH, AFC, BMI, prior response, coexisting pathology and fertility timeline. This page maps the major protocol types and the rationale behind each choice.

1. Why protocol matters

Stimulation protocol determines: number of eggs retrieved, egg quality (timing of trigger and exposure to stimulation), OHSS risk, cycle cancellation risk, embryo development outcomes, and ultimately live birth rate. Different protocols deliver different results in different patient subgroups. Individualisation is evidence-based, not optional.

2. Antagonist protocol — most common

Start FSH on day 2–3. Add GnRH antagonist (Cetrotide, Orgalutran) day 5–7 to prevent premature LH surge. Trigger when follicles 17–18 mm. Best for: most patients, including PCOS (lower OHSS risk than long agonist), normal responders, time-critical cases. Shorter duration (10–12 days). Lower OHSS risk than long agonist.

3. Long agonist protocol

GnRH agonist (Lupride, Buserelin) started in luteal phase of preceding cycle for downregulation. After confirmed suppression, FSH stimulation begins. Trigger when follicles mature. Best for: endometriosis (improved implantation rates per some studies), normal-good responders without OHSS concern. Longer duration (3–5 weeks total). Higher OHSS risk than antagonist.

4. Ultra-long protocol

GnRH agonist for 2–3 months before stimulation begins. Achieves deep suppression of endometriosis activity. Used for severe endometriosis with high disease activity. Adenomyosis cases. Some studies show improved implantation rates. Long duration limits utility for time-critical patients.

5. Mild stimulation / Mini-IVF

Lower FSH doses, sometimes with clomiphene or letrozole adjunct. Fewer eggs retrieved per cycle but lower medication burden. Best for: poor responders (high doses fail to recruit more follicles anyway), patients preferring minimal hormonal load, repeated full-dose IVF without success. May require more cycles for same cumulative success.

6. Poor responder protocols

DuoStim (dual stimulation in same cycle) — two retrievals 7–10 days apart, maximises egg recruitment in low-reserve patients. Estrogen priming before stimulation. Androgen priming (DHEA, testosterone) in selected cases — emerging evidence. Letrozole or clomiphene-assisted protocols. Microflare protocols. Each adapted to the specific poor-responder pattern.

7. Random-start protocols

For time-critical cases (cancer fertility preservation, urgent treatment). Stimulation begins at any cycle stage rather than waiting for cycle day 2–3. Outcomes comparable to standard timing in published studies. Critical for oncofertility — when waiting weeks is not possible before chemotherapy starts.

8. How protocol is chosen

Age and ovarian reserve (AMH, AFC) drive primary protocol selection. Coexisting conditions (PCOS for antagonist, endometriosis for long agonist or ultra-long). Prior cycle response in repeat cycles. Time constraints (oncofertility for random-start). Patient preference (mild stimulation for hormonal load minimisation). Decision is individualised at consultation and may be adjusted during cycle.

Frequently Asked Questions

Dr. Priyadatt Patel

Senior Gynecologist · Advanced Laparoscopic Surgeon · IVF and Endometriosis Programme Lead

MS OBGyn · Pregnancy Care · Advanced Gynaecological Ultrasound · Fertility Preservation

ESHRE / ESGE / AAGL / ASRM guideline-aligned practice. 3D Karl Storz precision technique. Fertility-preservation-first philosophy. Evidence-based decisions, honest counselling, long-term outcomes orientation.