Registry to evaluate COVID-19 vaccine effects during pregnancy

COVID-19 Vaccines International Pregnancy Exposure Registry (C-VIPER)

Observational Pregistry · NCT04705116

This study is testing how safe COVID-19 vaccines are for pregnant women and their babies by comparing their health outcomes to those of unvaccinated women.

Quick facts

Study typeObservational
Enrollment6000 (estimated)
Ages18 Years to 50 Years
SexFemale
SponsorPregistry Industry-sponsored
Locations1 site (Los Angeles, California)
Trial IDNCT04705116 on ClinicalTrials.gov

What this trial studies

The COVID-19 Vaccines International Pregnancy Exposure Registry (C-VIPER) aims to assess the safety and outcomes of COVID-19 vaccination in pregnant women and their infants. This observational study will compare obstetric, neonatal, and infant outcomes between vaccinated women and a matched group of unvaccinated women. Data will be collected on various health outcomes, including complications during pregnancy and developmental milestones in infants. The study is designed to provide valuable insights into the effects of COVID-19 vaccines on both mothers and their children.

Who should consider this trial

Good fit: Ideal candidates for this study are pregnant women aged 18 and older who have received at least one dose of a COVID-19 vaccine during pregnancy or within 30 days prior to their last menstrual period.

Not a fit: Patients who are not pregnant or who have not received a COVID-19 vaccine during the specified timeframe may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could provide critical information on the safety of COVID-19 vaccines for pregnant women and their babies.

How similar studies have performed: Other studies have begun to explore the safety of COVID-19 vaccines in pregnant populations, but this registry aims to provide more comprehensive data on a larger scale.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion criteria:

Vaccinated population:

* Pregnant at time of enrollment
* Age ≥18 years at time of enrollment
* Signed the informed consent form and submitted the baseline module "COVID-19 Vaccination During This Pregnancy"
* Received at least one dose of a COVID-19 vaccine during pregnancy or within the 30 days prior to the first day of the LMP
* Resident of a country where a Central Institutional Review Board (IRB) or Ethics Committee provided approval to conduct the study or clearance that approval is not required to conduct the study

Efforts will be made to obtain documentary evidence of COVID-19 vaccination.

Comparison population:

* Pregnant at time of enrollment
* Age ≥18 years at time of enrollment
* Signed the informed consent form and submitted the minimum required data in the initial baseline questionnaire
* Have not received a COVID-19 vaccine during pregnancy or within the 30 days prior to the first day of the LMP
* Resident of a country where a Central IRB or Ethics Committee provided approval to conduct the study or clearance that approval is not required to conduct the study

Exclusion criteria:

* Not pregnant at time of enrollment
* Age \<18 years at time of enrollment

Where this trial is running

Los Angeles, California

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 Covid19
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.