Maternal Oral Microbiota and Immune Signatures Associated With Spontaneous Labor Onset

NCT07839364 | Completed

• 1 other identifier: KY-2025-025
• Study Type: observational
• Target: 55
• Locations: 1 country
• Sites: 1

Brief Summary

This study investigates how the oral microbiome (the community of microorganisms living in the mouth) and immune system change around the time of spontaneous labor onset in healthy pregnant women. We will enroll 55 healthy pregnant women at full term (37 weeks or later). Participants will be divided into two groups: women who have begun labor and women who have not yet begun labor. We will collect saliva samples to analyze the oral bacteria using genetic sequencing, and collect blood and placental samples to measure immune factors (proteins that help regulate the body's immune response). By comparing the two groups, we aim to identify specific bacteria and immune factors that are associated with the start of labor. This research will help us better understand the biological processes that trigger childbirth and may contribute to improved prediction and management of labor onset.

Conditions

Labor Onset

Outcome Measures

Primary Outcomes (3)

• Differences in oral microbiota composition between labor-onset and non-labor groups

  Relative abundance of oral microbiota (%), assessed by 16S rRNA gene sequencing of the V3-V4 hypervariable regions (primers 341F/806R), with paired-end 2 x 250 bp sequencing on the Illumina NovaSeq 6000 platform, in saliva samples from 55 participants (LO, n = 28; NLO, n = 27)

  At sample collection (39-40 gestational weeks for NLO group; first stage of labor for LO group)

• Differences in plasma immune factor levels between labor-onset and non-labor groups

  Concentration of immune markers, including TLR-4, IFN-γ, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-18, IL-22, TNF-α, and IL-1β (pg/mL), in plasma, assessed by enzyme-linked immunosorbent assay (ELISA) using commercially available kits (Shanghai Fusheng Industrial Co., Ltd.), in 55 participants (LO, n = 28; NLO, n = 27)

  At sample collection (39-40 gestational weeks for NLO group; first stage of labor for LO group)

• Differences in placental immune factor levels between labor-onset and non-labor groups

  Concentration of immune markers, including TLR-4, IFN-γ, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-18, IL-22, TNF-α, and IL-1β (pg/mL), in placental tissue homogenates, assessed by enzyme-linked immunosorbent assay (ELISA) using commercially available kits (Shanghai Fusheng Industrial Co., Ltd.), in 50 participants (LO, n = 25; NLO, n = 25)

  At sample collection (placental tissues collected within 15 minutes postpartum)

Study Arms (2)

Labor-Onset Group (LO)

Other: None (Observational Study)

Non-Labor Group (NLO)

Other: None (Observational Study)

Interventions

None (Observational Study) OTHER

This is an observational study with no intervention administered. Participants are grouped based on the presence or absence of spontaneous labor onset.

Labor-Onset Group (LO); Non-Labor Group (NLO)

Eligibility Criteria

• Age: 18 Years - 35 Years
• Sex: female
• Age Groups: Adult (18-64)
• Sampling Method: Non-Probability Sample

Study Population

Healthy pregnant women at full term (37-40 gestational weeks) recruited from the Department of Obstetrics and Gynecology, The First Affiliated Hospital of Jinan University, Guangzhou, China. Participants are aged 18-35 years with a pre-pregnancy BMI of 18.5-23.9 kg/m², naturally conceived singleton pregnancies, and no obstetric complications. Participants are grouped according to the presence or absence of spontaneous labor onset: labor-onset group (LO, n=28) and non-labor group (NLO, n=27).

You may qualify if:

• Pregnant women aged 18 to 35 years
• Pre-pregnancy body mass index (BMI) of 18.5 to 23.9 kg/m²
• Naturally conceived singleton pregnancy
• No obstetric complications
• Written informed consent obtained prior to enrollment

You may not qualify if:

• Polyhydramnios, oligohydramnios, gestational hypertension, gestational diabetes, or other pregnancy-related disorders
• History of cervical surgery or previous preterm birth
• Antibiotic or probiotic use during the current pregnancy
• Current oral diseases or dental/oral procedures within the previous six months
• Uterine malformations
• Chronic conditions such as immune system disorders, hypertension, diabetes, gastrointestinal diseases, or hyperthyroidism
• Smoking, alcohol consumption, or other adverse lifestyle habits

Sponsors & Collaborators

• Third Affiliated Hospital, Sun Yat-Sen University: lead

Study Sites (1)

Zhe Li

Guangzhou, China

Location

MeSH Terms

Interventions

Observation

Intervention Hierarchy (Ancestors)

Methods; Investigative Techniques

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Target Duration: 2 Weeks
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: September 11, 2026
• First Posted: September 24, 2026
• Study Start: January 22, 2025
• Primary Completion: January 22, 2026
• Study Completion: January 22, 2026
• Last Updated: September 24, 2026

Record last verified: 2026-09

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)