Researchers in a 2026 guideline review provide evidence-based recommendations from ESHRE on ovarian stimulation for IVF/ICSI, covering protocols, medications, monitoring, and safety.
Ovarian stimulation is used in IVF to develop multiple follicles and retrieve several eggs, with the goal of improving success rates while minimizing risks like ovarian hyperstimulation syndrome (OHSS).
This guideline includes 121 recommendations across 21 key questions, based on studies published up to February 2025, focusing on live birth and safety outcomes. These are official recommendations by the European Society of Human Reproduction and Embryology (ESHRE).
Most recommendations are based on low or very low-quality evidence, with none supported by high-quality evidence. Despite this, they reflect the current state of the data and are intended to help guide ovarian stimulation in clinical practice.
Here, I focus on two types of recommendations used by ESHRE:
- Strong recommendations, which are intended to apply to most patients.
- Conditional recommendations, which depend more on individual patient factors and clinical judgment. These use language like “probably recommended” to reflect uncertainty.
This is a simplified, selected summary of the guideline. The full document is open access and includes additional recommendations along with the evidence used to support each one.
🔗 Original studies are referenced in this post or within the linked Remembryo posts.
💡 Reminder: Terms underlined with a dotted black line are linked to glossary entries. Clicking these does not count toward your paywall limit.
Pre-stimulation evaluation
Strong recommendations
- Use AMH or AFC to predict ovarian response
- Ovarian reserve markers (AMH, AFC) shouldn’t be used to predict the chance of pregnancy or live birth
- Female age and BMI are predictors of pregnancy and live birth
Pre-treatment therapies
Strong recommendations
- Estrogen pre-treatment is not recommended to improve outcomes in GnRH antagonist cycles
- Pretreatment with combined oral contraceptives is not recommended for GnRH antagonist protocols using FSH stimulation
Conditional recommendations
- GnRH antagonist pre-treatment (delayed-start) is probably not recommended
Pituitary suppression and ovarian stimulation
Strong recommendations
- GnRH antagonist protocol is recommended for high responders
- Avoid gonadotropin doses >300 IU in low responders
- GnRH antagonist protocols are recommended over GnRH agonist protocols due to similar live birth rates and lower OHSS risk
- If a GnRH agonist protocol is used, the long protocol is recommended over short or ultrashort protocols
Conditional recommendations
- Reduced gonadotropin doses (100–150 IU) are probably recommended in high responders
- Increasing or decreasing dose vs standard (150–225 IU) in normal responders likely doesn’t improve outcomes
- Adjusting dose mid-cycle is probably not recommended
Type of stimulation drugs
Strong recommendations
- rFSH and hMG are equally recommended
- Follitropin delta and follitropin alpha/beta are equally recommended
Conditional recommendations
- Adding LH to FSH is probably equivalent to FSH alone (no clear benefit)
- Combining FSH with hMG is probably not beneficial
Ovarian stimulation add-ons
Strong recommendations
- Growth hormone is not recommended (including for normal responders and PCOS)
- DHEA is not recommended (including for low and normal responders)
- Aspirin is not recommended (including for the general population and low responders)
- Sildenafil (Viagra) is not recommended for low responders
- Myo-inositol is not recommended (including for low responders and non-PCOS patients)
Conditional recommendations
- Letrozole with gonadotropins is probably not recommended for normal, low, and high responders
- Clomiphene with gonadotropins is probably not recommended for normal and high responders
- Growth hormone in low responders is probably not recommended
- Testosterone in low responders is probably not recommended
Monitoring
Strong recommendations
- Serum estradiol and LH measurements are not recommended on the day of hCG trigger in fresh cycles
- Serum estradiol, progesterone, and LH measurements are not recommended on the day of a GnRH agonist trigger in freeze-all cycles
Conditional recommendations
- Measuring progesterone on trigger day may be useful for deciding fresh vs freeze-all
- Routine endometrial thickness monitoring during ovarian stimulation is probably not recommended
Cycle cancellation
Strong recommendations
- A low response to ovarian stimulation alone is not a reason to cancel a cycle
- To prevent OHSS, withhold trigger in GnRH agonist cycles with ≥19 follicles ≥11 mm
Triggering ovulation and luteal support
Strong recommendations
- GnRH agonist trigger is not recommended in the general IVF/ICSI population with fresh transfer
- Progesterone is recommended for luteal phase support
- In hCG-triggered cycles, hCG is not recommended for luteal phase support in standard doses
Conditional recommendations
- Lower hCG dose (5000 vs 10,000 IU) may be safer
- Dual trigger (GnRH agonist + hCG) is probably not recommended for normal and low responders
- Adding estradiol to progesterone for luteal phase support is probably not recommended
Prevention of OHSS
Strong recommendations
- GnRH agonist trigger combined with a freeze-all strategy is recommended to minimize the risk of severe OHSS
- Freeze-all strategy is recommended to minimize the risk of late-onset OHSS
Conditional recommendations
- GnRH agonist trigger is probably preferred over hCG when no fresh transfer is planned
- Dual trigger is probably not recommended in high responders
Putting this into practice
ESHRE also provides a simplified overview of how these recommendations are applied in practice. These are general patterns based on ESHRE’s recommendations, but treatment is individualized based on patient characteristics and clinic approach.
In general:
- Low responders are typically treated with either a GnRH antagonist or agonist protocol, using higher gonadotropin doses (150–300 IU), followed by an hCG trigger (10,000 IU hCG or 250 µg recombinant hCG) and, if doing a fresh transfer, luteal phase support with progesterone is recommended
- Normal responders are typically treated with a GnRH antagonist protocol as the first choice (agonist as an alternative), using moderate doses (150–225 IU), followed by an hCG trigger (10,000 IU hCG or 250 µg recombinant hCG) and, if doing a fresh transfer, luteal phase support with progesterone is recommended
- High responders are typically treated with a GnRH antagonist protocol as the first choice (with progestin or agonist protocols as alternatives), using lower gonadotropin doses (100–150 IU), and may use a GnRH agonist trigger with a freeze-all approach to reduce OHSS risk
ESHRE provides a much more detailed breakdown in the full guideline, including additional recommendations and the evidence used to support each one. The document is open access and worth reviewing for anyone who wants a deeper look.
Want to read more guidance from ESHRE?
Researchers in 2023 provided evidence-based guidelines for deciding how many embryos to transfer, as prepared by ESHRE. Read more.
Researchers in 2023 provide evidence-based guidelines for managing patients with unexplained infertility, as prepared by ESHRE. Read more.
Researchers in a 2023 study review the use of 27 IVF add-ons and provide recommendations by ESHRE, with only several that are recommended or could be considered for the general infertility population. Read more.
Reference
About Embryoman
Embryoman (Sean Lauber) is a former embryologist and the founder of Remembryo, an IVF research and fertility education website. After working in an IVF lab in the US, he returned to Canada and now focuses on making fertility research more accessible. He holds a Master’s in Immunology and launched Remembryo in 2018 to help patients and professionals make sense of IVF research. Sean shares weekly study updates on Facebook, Instagram, and Reddit regularly. He also answers questions on Reddit or in his private Facebook group.