Clinical trial NCT03809390: Effects of Vaginal Seeding on Infants' Body Mass Index and Allergy Risk for Caesarean-delivered Children
Official title: Effects of Vaginal Seeding on Infants' Body Mass Index and Allergy Risk for Caesarean-delivered Children: A Randomized Controlled Study
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Overweight and Obesity
Allergy
Keywords: Body mass index
Allergic risk
Vaginal seeding
Randomized controlled study
Caesarean delivery
Overweight and obesity
Lead sponsor: Peking University
Sponsor class: OTHER
Collaborators: name: National Natural Science Foundation of China
name: Liuyang Maternal and Child Health Care Hospital
First posted: 2019-01-18
Enrollment: 117
Sex: FEMALE
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: PREVENTION

Brief summary: 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.

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.

Eligibility criteria: 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

Primary outcomes:
measure: infant's body mass index
timeFrame: At 6 months
measure: infant's body mass index
timeFrame: At 12 months
measure: infant's body mass index
timeFrame: At 18 months
measure: infant's body mass index
timeFrame: At 24 months
measure: infant's allergy risk score
timeFrame: At 18 months after birth
Secondary outcomes:
measure: Infants' gut microbiota profile
timeFrame: At baseline (Meconium), 6, 12 ,18 and 24 months after birth
measure: Rate of overweight/obesity
timeFrame: At 6, 12 ,18 and 24months
measure: Rate of allergic symptoms and common allergic diseases
timeFrame: At 61, 12 ,18 and 24 months
measure: Rate of adverse effects
timeFrame: From birth to 24 months
Other outcomes:
Locations:
city: Liuyang
country: China
facility: Liuyang Maternal and Child Health Care Hospital
state: Hunan
Study officials:
affiliation: Peking University
name: Jian-meng Liu, PhD
role: STUDY_CHAIR
affiliation: Peking University
name: Hong-tian Li, PhD
role: PRINCIPAL_INVESTIGATOR
affiliation: Liuyang Maternal and Child Health Care Hospital
name: Shujin Zhou, MD
role: STUDY_DIRECTOR
affiliation: Peking University
name: Yang Liu, PhD Candidate
role: STUDY_DIRECTOR
References: