When to start hormones after stopping combined birth control for planned egg freezing

A Randomized Blinded Controlled Trial Assessing Hormonal Optimization: Late vs. Immediate Start After Discontinuation of Oral Contraceptives in Assisted Reproductive technologY (HOLIDAY)

Not applicable Interventional Shady Grove Fertility Reproductive Science Center · NCT07225660

This trial tests whether taking a two-month break from combined hormonal birth control versus starting ovarian stimulation immediately affects outcomes for ovary-bearing people aged 18–40 who are planning to freeze their eggs.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment394 (estimated)
Ages18 Years to 40 Years
SexFemale
SponsorShady Grove Fertility Reproductive Science Center Academic / other
Locations3 sites (Orange, Connecticut and 2 other locations)
Trial IDNCT07225660 on ClinicalTrials.gov

What this trial studies

HOLIDAY is a multi-center, two-arm, parallel-group randomized trial comparing a 2-month pause from combined hormonal contraception (CHC) to immediate initiation of ovarian stimulation without a pause. Participants are ovary-bearing individuals aged 18–40 with BMI under 40 and who have not smoked for at least three months. Those randomized will undergo standard ovarian stimulation and egg retrieval according to clinic protocols, with outcomes related to stimulation response and oocyte yield collected. The trial is being run at three U.S. fertility centers and supported by an industry collaborator.

Who should consider this trial

Good fit: Ovary-bearing individuals aged 18–40 with BMI <40 kg/m2, who have been non-smokers for at least three months and are planning oocyte cryopreservation while using combined hormonal contraception are ideal candidates.

Not a fit: People with BMI ≥40 kg/m2, current smokers, or those with contraindications to ovarian stimulation or outpatient egg retrieval under anesthesia are excluded and unlikely to benefit from participation.

Why it matters

Potential benefit: If successful, the trial could clarify the best timing to start stimulation after stopping CHC and potentially improve scheduling or egg-yield outcomes for people pursuing planned oocyte cryopreservation.

How similar studies have performed: Prior observational work suggests hormonal contraception timing can affect ovarian response, but randomized multicenter data on a fixed 2-month pause versus immediate start are limited, making this a relatively novel randomized comparison.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Ovary-bearing individuals 18 to 40 years of age.
2. BMI \< 40 kg/m2
3. Non-smoker for at least 3 months prior to study enrollment.

Exclusion Criteria:

1. BMI greater than or equal to 40 kg/m2
2. Current Smoker
3. Any contraindications to ovarian stimulation or outpatient egg retrieval under anesthesia

Where this trial is running

Orange, Connecticut and 2 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Fertility Preservationplanned oocyte cryopreservation
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.