Peri-conceptional or Pregnancy Exposure of Vaccination and the Risk of Adverse Pregnancy Outcomes

Study Overview
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Brief Summary
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Uing data from a population based cohort in China, we will conduct retrospective cohort study to evaluate the risk of vaccine (e.g., HPV/influenza/rabies vaccine) administered during pregnancy (especially during first trimester) for adverse pregnancy outcomes (e.g., birth defects, preterm birth and low birth weight)

Detailed Description
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We will develop a vaccination cohort by linking population-based pregnancy registries (i.e., REPRESENT) with population-based vaccine databases. The researchers will use data from this cohort to examine vaccine use 90 days before the last menstrual period and throughout pregnancy. This study will investigate whether maternal vaccination during pregnancy is associated with the risk of adverse pregnancy outcomes. Poisson regression based on propensity scores will be used to estimate the relative risk. To ensure the robustness of the results, the researchers will perform several sensitivity analyses and negative control analyses, such as the risk of adverse pregnancy outcomes in pregnant women who have been vaccinated several times and pregnant women who have been vaccinated in mid and late pregnancy as negative control groups.

Official Title
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Peri-conceptional or Pregnancy Exposure of Vaccination and the Risk of Adverse Pregnancy Outcomes

Conditions
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Vaccine Adverse Reaction

Intervention / Treatment
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* Biological: Hepatitis B vaccine, rabies vaccine, HPV vaccine, influenza vaccine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All pregnant women in Xiamen who registry in our database. Exclusion Criteria: Pregnant women who were lost to follow-up. Pregnant women exposed to related factors of known congenital malformation.

Ages Eligible for Study
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Minimum Age: 14 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Biological: Hepatitis B vaccine, rabies vaccine, HPV vaccine, influenza vaccine|Exposure was defined as use of the vaccine 90 days before the last menstrual period and during pregnancy.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Birth defects | BDs were defined as any prenatal malformation (including structural, functional, or metabolic disorders) diagnosed through systematic ultrasound or genetic testing during pregnancy and any malformation diagnosed by clinicians within 42 days of birth，which were coded according to the International Classification of Diseases, Tenth Revision (ICD-10) (Q00-Q99). | From pregnancy to 42 days after delivery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of Adverse pregnancy outcomes | Including gestational diabetes, fetal distress, premature rupture of membranes, low birth weight and so on. | From pregnancy to 42 days after delivery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Vaccine, birth defect, adverse pregnancy outcomes