Skip to main content
OpenTrials
Completed

NCT Number: NCT06131749

Genital Tract Infections, the Vaginal Microbiome and Gestational Age at Birth Among Pregnant Women in South Africa

This cohort study plans to investigate associations between the presence of multiple lower genital tract microorganisms in pregnancy and gestational age at birth.

The study enrols pregnant women at one public health care facility in East London, South Africa. At enrolment and 30-34 weeks of pregnancy, participants provide swabs for testing for sexually transmitted infections, vaginal yeasts and genital mycoplasmas; for microscopy and Nugent scoring; and for 16S ribosomal ribonucleic acid gene sequencing and quantification. The primary outcome is gestational age at birth.

Statistical analyses include: regression modelling to explore associations between specific microorganisms (including microbiota) and gestational age at birth; construction of an index of vaginal inflammation, using data about microorganism load and inflammatory potential; classification and regression tree analysis to examine which combinations of microorganisms contribute to earlier gestational age at birth.

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Sexually Transmitted Infections (Not HIV or Hepatitis) Bacterial Infections Bacterial Infections and Mycoses Bacterial Vaginosis Blood-Borne Infections Candidiasis Candidiasis, Vulvovaginal Chlamydia Trachomatis Infection Communicable Diseases Digestive System Diseases Disease Attributes Female Urogenital Diseases Female Urogenital Diseases and Pregnancy Complications Genital Diseases Genital Diseases, Female Genital Mycoplasma Infection Gonorrhea Gram-Negative Bacterial Infections HIV Infections Hepatitis Immune System Diseases Immunologic Deficiency Syndromes Infections Lentivirus Infections Liver Diseases Microbial Colonization Mycoplasma Genitalium Infection Mycoses Neisseria Gonorrheae Infection Neisseriaceae Infections Obstetric Labor Complications Obstetric Labor, Premature Parasitic Diseases Pathologic Processes Pathological Conditions, Signs and Symptoms Pregnancy Complications Pregnancy Complications, Infectious Pregnancy; Infection Premature Birth Protozoan Infections RNA Virus Infections Retroviridae Infections Sexually Transmitted Diseases Sexually Transmitted Diseases, Bacterial Sexually Transmitted Diseases, Viral Trichomonas Infections Trichomonas Vaginitis Ureaplasma Urealyticum Infection Urogenital Diseases Vaginal Candida Vaginal Diseases Vaginitis Vaginosis, Bacterial Virus Diseases Vulvar Diseases Vulvitis Vulvovaginitis

Age range

18 year and older

Sex eligibility

Female

Study type

Observational

Primary location

Empilweni Gompo Community Health Centre

East London, Eastern Cape, 5209, South Africa

About this study

Background: Preterm birth complications are the most common cause of death in children under 5 years. In South Africa, the prevalence of both genital tract infections and adverse pregnancy outcomes are high. This study takes a holistic approach, investigating both the presence and quantity of multiple lower genital tract microorganisms, including vaginal microbiota, in pregnancy and their associations with gestational age at birth. Specific objectives are to explore: (1) the association between the presence of specific lower genital tract microorganisms and gestational age at birth (primary outcome), as well as secondary adverse pregnancy outcomes; (2) the association between quantified load of vaginal and sexually transmitted microorganisms and gestational age at birth (primary outcome) as well as secondary adverse pregnancy outcomes; and (3) the combinations of microorganisms that are most strongly associated with earlier gestational age at birth.

Methods: This prospective closed cohort study follows women enrolled during pregnancy until after they give birth. This cohort study is part of a larger project, called Philani Ndiphile (meaning 'be healthy and I will be healthy' in isiXhosa).

A trained study field worker checks for eligibility and obtains written informed consent. A study nurse performs an abdominal ultrasound to estimate the gestational age and confirm eligibility.

At the enrolment visit and a follow-up visit at 30-34 weeks, a study nurse collects vaginal specimens for: on-site testing for Chlamydia trachomatis and Neisseria gonorrhoeae (with antibiotic treatment if positive); and offsite testing for: Nugent scoring; detection and quantification of Mycoplasma genitalium, M. hominis, Ureaplasma. parvum, U. Urealyticum, Trichomonas vaginalis, Candida spp. and 16S rRNA amplicon sequencing for vaginal microbiota analyses.

At a post-natal visit, 3-6 days after giving birth, a study nurse collects information about the birth outcome.

Statistical analyses include:

Objective 1. a) univariable and multivariable regression analyses for associations between specific microorganisms and gestational age at birth. b) compositional multivariable analysis methods to analyse individual taxon relative abundances and mixed effects models to assess associations between pregnancy outcome and vaginal microbiota diversity, vaginal microbiota types and absolute abundances of predefined bacterial groups.

Objective 2. Development of a 'vaginal inflammation index', based on quantification of the vaginal microbiota and their inflammatory potential. This vaginal inflammation index will be analysed as a fixed effect in mixed effects models with pregnancy outcomes.

Objective 3. Classification and regression tree analyses to examine the combination of microorganisms that best predicts earlier gestational age at birth.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Living in Buffalo City Metropolitan Municipality
  • Intend to deliver in the same municipality
  • <27 weeks of gestation at enrolment, confirmed by ultrasound
  • Provide written informed consent

Exclusion criteria

  • Participation in any other research study
  • Inability to understand and speak a local language (English, Afrikaans, or isiXhosa).

Treatment and study plan

No intervention

Other

No intervention, observational cohort study

Primary outcomes

  1. Gestational age at birth

    Time frame: Recorded within 2 weeks of delivery

    Gestational age in days, estimated using data from obstetric ultrasound at enrolment visit

Secondary outcomes

  1. Preterm birth

    Time frame: Recorded within 2 weeks of birth

    Number of babies liveborn before 37 completed weeks of pregnancy, estimated using data from obstetric ultrasound at enrolment visit

  2. Low birth weight

    Time frame: Measured within 72 hours of birth

    Number of babies with birth weight <2500g

  3. Miscarriage

    Time frame: Collected throughout pregnancy until delivery

    Number of foetuses delivered dead before 28 completed weeks of pregnancy or with birth weight below 1000g. Gestational age estimated using data from obstetric ultrasound at enrolment visit

  4. Stillbirth

    Time frame: Collected throughout pregnancy until delivery

    Number of foetuses delivered dead at or after 28 completed weeks of pregnancy or with birth weight above 1000g at delivery. Gestational age estimated using data from obstetric ultrasound at enrolment visit

Other outcomes

  1. Prevalence of microorganisms

    Time frame: Measured at enrolment visit and at 30-34 week visit

    Number of women with a specific microorganism / number of women tested

  2. Incidence of microorganisms

    Time frame: Measured at 30-34 week visit

    Number of women with new detection of a specific microorganism per 1000 woman years of follow-up

Sponsors and collaborators

Lead sponsor

University of Bern

Other

Collaborators

  • Foundation for Professional Development
  • Louisiana State University Health Sciences Center in New Orleans
  • University of Alabama at Birmingham
  • University of Cape Town
  • University of Pretoria
  • University of Southern California
  • Utrecht University

Registry information

Important dates

Study start
2021
Primary completion
2024
Study completion
2024
First posted
Nov 14, 2023
Registry last updated
Sep 16, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.