Natural Versus Programmed Frozen Embryo Transfer (NatPro)
Public ClinicalTrials.gov record NCT04551807. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.
Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.
Official title
Multi-center, Parallel-group, Randomized Controlled Trial of Modified Natural Versus Programmed Cycles for Frozen Embryo Transfers and Their Association With Preeclampsia and Live Births
Brief summary
Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.
NatPro is a two-arm, parallel-group, multi-center, randomized trial in which women undergoing frozen embryo transfer (FET) will be randomized to receive either a modified natural cycle (corpus luteum present) or a programmed cycle (corpus luteum absent).
Study identification
- NCT ID
- NCT04551807
- Recruitment status
- Active, not recruiting
- Study type
- Interventional
- Phase
- Phase 3
- Enrollment
- 788 participants
Conditions and interventions
Conditions
Eligibility (public fields only)
- Age range
- 18 Years to 41 Years
- Sex
- Female
- Healthy volunteers
- Accepts healthy volunteers
This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.
Study timeline
- Start date
- Sep 16, 2020 (Actual)
- Primary completion
- Feb 1, 2026 (Estimated)
- Completion
- Apr 1, 2026 (Estimated)
- Last update posted
- May 16, 2025
2020 – 2026
United States locations
- U.S. sites
- 15
- U.S. states
- 13
- U.S. cities
- 15
| Facility | City | State | ZIP | Site status |
|---|---|---|---|---|
| University of California San Francisco | San Francisco | California | 94158 | — |
| Stanford University | Sunnyvale | California | 94087 | — |
| Yale | Orange | Connecticut | 06477 | — |
| Fertility Institute of Hawaii | Honolulu | Hawaii | 96814 | — |
| Northwestern University | Chicago | Illinois | 60611 | — |
| Johns Hopkins | Baltimore | Maryland | 21093 | — |
| Shady Grove Fertility | Rockville | Maryland | 20850 | — |
| Boston IVF | Waltham | Massachusetts | 02451 | — |
| University of Rochester | Rochester | New York | 14642 | — |
| Atrium Health | Charlotte | North Carolina | 28203 | — |
| Cleveland Clinic Foundation | Beachwood | Ohio | 44122 | — |
| University of Oklahoma | Oklahoma City | Oklahoma | 73104 | — |
| University of Pennsylvania | Philadelphia | Pennsylvania | 19104 | — |
| CARE Fertility | Bedford | Texas | 76022 | — |
| West Virginia University Center for Reproductive Medicine | Morgantown | West Virginia | 26505 | — |
Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.
About this trial record page
- What this page shows
- Public field values for ClinicalTrials.gov record NCT04551807, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
- What this page does not do
- No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
- Where the data comes from
- Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
- Last refresh
- Last update posted May 16, 2025 · Synced Oct 18, 2026
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Open the official record
The complete public registry record, listed eligibility criteria, and available contact information for NCT04551807 live on ClinicalTrials.gov.