Effects of Vaginal Seeding on Infants' Body Mass Index and Allergy Risk for Caesarean-delivered Children

Effects of Vaginal Seeding on Infants' Body Mass Index and Allergy Risk for Caesarean-delivered Children: A Randomized Controlled Study

This is a single-blind randomized controlled trial, aiming to evaluate the effects of vaginal seeding on body mass index as well as allergy risk for cesarean-delivered infants. It will be conducted in Liuyang city of China, and the targeted sample size is 106. All the eligible pregnant women will be randomly assigned to either the intervention or control group, and their babies of the participants will be followed up to 24 months of age.

Study Overview

• Status: Active, not recruiting
• Conditions: Allergy; Overweight and Obesity
• Intervention / Treatment: Procedure: Vaginal seeding

Detailed Description

Many studies have suggested that caesarean-delivered children are at higher risks of developing metabolic and allergic diseases like obesity and asthma, possibly because newborns born by caesarean section were lack of exposure to maternal vaginal flora. It is needed to explore a simple, convenient, and safe intervention strategy to reduce caesarean-related risks. In a recent non-randomized study, the authors found that exposure of caesarean-delivered newborns to maternal vaginal fluid at birth (i.e., vaginal seeding) could partially restore the microbiota of them at 30 days after births, but the long-term health consequences of restoring the microbiota of caesarean-delivered infants remain unclear.

In this randomized study, the investigators aim to examine whether the changes in newborns' microbiota will persist to 24 month of age, and whether vaginal seeding will have any effects on body mass index and allergy risk from birth to 24 months of age. the investigators will enroll a total of 106 pregnant women, and the participants' infants will be followed up at 0 (before hospital discharge), 6, 12, 18 and 24 months. At each follow-up visit, a questionnaire survey including information on feeding, medication, and allergic status will be conducted, infants' height and weight will be measured, and feces will be collected. At 18-month-old visit, infants' venous blood will be also collected for the assay of multiallergen. The primary outcomes were body mass index and allergy risk index. The secondary outcomes included the microbiota profile, allergic symptoms and diseases, overweight/obesity, and adverse effects.

• Study Type: Interventional
• Enrollment (Actual): 117
• Phase: Not Applicable

Contacts and Locations

Study Locations

• China
  • Hunan
    • Liuyang, Hunan, China, 410399
      • Liuyang Maternal and Child Health Care Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: ADULT; OLDER_ADULT; CHILD
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Female

Description

Inclusion Criteria:

• local resident in Liuyang city
• Singleton, term pregnancy (≥37 weeks of gestation)
• Cesarean section before labor starts without maternal complications, or cesarean section after the start of labor but the cervix is less than 3 cm
• Vaginal pH< 4.5 at enrollment

Exclusion Criteria:

• Positive testing for HIV, HBV, syphilis or GBS infection at gestation
• Vaginal infections such as genital herpetic lesions or chlamydia
• Bacterial vaginosis
• Trichomonas or fungous in leucorrhea
• Pregnant women or her spouse with severe allergic diseases, such as asthma and severe drug allergy
• Vaginal pH ≥4.5 at 1-2 hours before the cesarean section
• Other conditions not suitable for intervention as judged by obstetricians

Study Plan

How is the study designed?

Design Details

• Primary Purpose: PREVENTION
• Allocation: RANDOMIZED
• Interventional Model: PARALLEL
• Masking: SINGLE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: Vaginal seeding group; Swabbing infants born by C-section with a gauze incubated in the maternal vagina about an hour before the C-section. The gauze will be extracted prior to the C-section, kept in a sterile container in an incubator (37 ℃), and taken out from the incubator immediately before the swabbing. The infant will be swabbed with the gauze, starting from the lips, followed by the face, thorax, arms, legs, genitals and anal region, and finally the back. The swabbing will take around 15-20 seconds.	Procedure: Vaginal seeding; The same as that stated in arm descriptions.
NO_INTERVENTION: Control group; Managed based on the standard practice in the study site

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
infant's body mass index	Body mass index in original scale and z-score	At 6 months
infant's body mass index	Body mass index in original scale and z-score	At 12 months
infant's body mass index	Body mass index in original scale and z-score	At 18 months
infant's body mass index	Body mass index in original scale and z-score	At 24 months
infant's allergy risk score	Calculated based on the measurements of multiallergens with 0-6 classes,higher values represent a worse outcome which means more susceptible to allergic diseases	At 18 months after birth

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Infants' gut microbiota profile	Intestinal flora will be detected by 16sRNA sequencing using feces samples	At baseline (Meconium), 6, 12 ,18 and 24 months after birth
Rate of overweight/obesity	Defined by body mass index	At 6, 12 ,18 and 24months
Rate of allergic symptoms and common allergic diseases	Collected by using a structured questionnaire	At 61, 12 ,18 and 24 months
Rate of adverse effects	Infection-related diseases and others	From birth to 24 months

Collaborators and Investigators

• Sponsor: Peking University
• Collaborators: National Natural Science Foundation of China; Liuyang Maternal and Child Health Care Hospital
• Investigators: Study Chair: Jian-meng Liu, PhD, Peking University; Principal Investigator: Hong-tian Li, PhD, Peking University; Study Director: Shujin Zhou, MD, Liuyang Maternal and Child Health Care Hospital; Study Director: Yang Liu, PhD Candidate, Peking University

Study record dates

Study Major Dates

• Study Start (ACTUAL): November 17, 2018
• Primary Completion (ACTUAL): September 20, 2021
• Study Completion (ANTICIPATED): November 1, 2022

Study Registration Dates

• First Submitted: November 17, 2018
• First Submitted That Met QC Criteria: January 17, 2019
• First Posted (ACTUAL): January 18, 2019

Study Record Updates

• Last Update Posted (ACTUAL): December 10, 2021
• Last Update Submitted That Met QC Criteria: December 9, 2021
• Last Verified: December 1, 2021

More Information

Terms related to this study

• Keywords: Body mass index; Randomized controlled study; Caesarean delivery; Vaginal seeding; Allergic risk; Overweight and obesity
• Additional Relevant MeSH Terms: Immune System Diseases; Body Weight; Hypersensitivity; Overweight
• Other Study ID Numbers: NSFC.81701538

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: The IPD will be shared upon the request of other researchers, and all the key variables that will be reported in the main paper are planned to be shared
• IPD Sharing Time Frame: After the publication of the main paper (hopefully before the end of 2022), the data will be available to share to other researchers
• IPD Sharing Access Criteria: Researchers should request the data via the following Email: lihongtian@pku.edu.cn or liujm@pku.edu.cn
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; ICF; ANALYTIC_CODE

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No