Longitudinal assessment of bacterial vaginosis prior to and during incident pregnancy: an observational study in Kenyan adolescent girls and young women
Stacy Selke,
Anna Wald,
Alison Roxby,
Kenneth Ngure,
Nelly Mugo,
Lynda Oluoch,
Bhavna Chohan,
Catherine Kiptinness,
Kenneth Tapia,
Stephen Gakuo Maina,
Edinah Casmir,
L Makena,
Melody Wang,
Laura Sycuro
Affiliations
Stacy Selke
Laboratory Medicine and Pathology, University of Washington, Seattle, Washington, USA
Anna Wald
Medicine, Laboratory Medicine and Pathology, Epidemiology, University of Washington, Seattle, Washington, USA
Alison Roxby
Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
Kenneth Ngure
Community Health, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
Nelly Mugo
Center for Clinical Research, Kenya Medical Research Institute, Nairobi, Kenya
Lynda Oluoch
Center for Clinical Research, Kenya Medical Research Institute, Nairobi, Kenya
Bhavna Chohan
Center for Clinical Research, Kenya Medical Research Institute, Nairobi, Kenya
Catherine Kiptinness
Center for Clinical Research, Kenya Medical Research Institute, Nairobi, Kenya
Kenneth Tapia
Global Health, University of Washington, Seattle, Washington, USA
Stephen Gakuo Maina
Data Department, Kenya Medical Research Institute, Nairobi, Kenya
Edinah Casmir
Department of Global Health, University of Washington, Seattle, Washington, USA
L Makena
Kenya Medical Research Institute (KEMRI), Nairobi, Kenya
Melody Wang
Global Health, University of Washington, Seattle, Washington, USA
Laura Sycuro
Department of Microbiology, Immunology and Infectious Diseases; Obstetrics and Gynecology; Snyder Institute for Chronic Diseases; Alberta Children’s Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
Objective To determine bacterial vaginosis (BV) status at multiple time points among adolescent girls and young women (AGYW) and assess the impact of pregnancy on their BV status.Design Longitudinal cohort study.Setting Thika, Kenya.Participants AGYW aged 16–20 years enrolled prior to first sex or reporting only a single lifetime partner.Main outcome measures The primary outcome was relative risk (RR) of BV during pregnancy compared with before pregnancy by analysing longitudinal trends in BV over time. BV risk was estimated using Poisson regression models.Results A total of 121 AGYW became pregnant in the parent cohort and had BV results before, during or after pregnancy. Point prevalence of BV was 11.0% at visits >12 months pre-pregnancy, 13.0% at 3–12 months pre-pregnancy, 22.1% at <3 months pre-pregnancy and 13.4% during pregnancy. Compared with visits during pregnancy, RR of BV was 1.65 (95% CI: 1.00 to 2.71; p=0.05) at visits <3 months pre-pregnancy, 0.97 (95% CI: 0.62 to 1.52; p=0.90) at visits 3–12 months pre-pregnancy and 0.82 (95% CI: 0.44 to 1.53; p=0.53) at visits 12 months pre-pregnancy. An adjusted analysis including age, income, residence, date of first sex, recent sexual activity and positive sexually transmitted infection test resulted in small changes in risk estimates, with adjusted RR of BV of 1.66 (95% CI: 1.04 to 2.67; p=0.04) at visits <3 months pre-pregnancy compared with visits during pregnancy.Conclusions BV risk during pregnancy was lower than during the immediate pre-pregnancy period. Hormonal changes in pregnancy may reduce BV.
