The New Indian Journal of OBGYN. 12(1):163-166

A study on abnormal vaginal pH in the midtrimester of pregnancy as a screening predictor of preterm labor in asymptomatic patients: a randomized controlled trial

Marin Paulson, Aswath Kumar, Annie Kuriyan, Jobinse Jose

ABSTRACT

Objectives: The aim of the study is to screen for abnormal vaginal pH in the mid trimester of pregnancy in asymptomatic patients and to assess whether abnormal pH is an indicator of PTB. Methodology: Randomised controlled trial conducted in the outpatient department of a tertiary care hospital from March 2019 to August 2020. Total of 170 asymptomatic pregnant women with gestational age between 13 and 22 weeks who had a vaginal pH more than 4.5 were randomised for either treatment with clindamycin vaginal tablet for three days or with no pharmacological intervention. A vaginal smear was also prepared to diagnose bacterial vaginosis. The patients were followed up until delivery and the gestational age at birth, birth weight of the newborn and the perinatal outcome were recorded. Results: The preterm delivery was more in the control group (54.8%) than the case group (4%) and was mostly late preterm births. Mean gestational age was 34 weeks and the mean birth weight was 2.2.kg. Gram staining showed bacterial vaginosis in both case and control groups. Conclusions: Abnormal vaginal pH is a better predictor of preterm labor even in asymptomatic pregnant women. The study also suggests a method for using intravaginal bacterial findings during pregnancy as a biomarker to evaluate the risk of preterm delivery.