Maternal recto-vaginal and colonization of GBS & its association with early onset of neonatal sepsis

Maternal recto-vaginal and colonization of GBS


Within the cohort study, we are conducting a cross-sectional study to determine the prevalence of maternal vaginal or rectal colonization of GBS during pregnancy (≥ 30 weeks of gestational age and during delivery) and the vertical transmission rate of GBS from colonized pregnant woman to infant along with its association to develop early onset of neonatal sepsis among vaginal birth. We will follow their newborns born vaginally through the first seven days and up to one month of life and screen for signs of early-onset neonatal infection. To explore the relationships between chorioamnionitis, maternal clinical signs and risk factors of intrapartum infection, and early-onset neonatal sepsis among those newborns born vaginally, we are collecting placental samples and maternal clinical signs and risk factors during labor and delivery.


Group B Streptococcus (GBS) or Streptococcus agalactiae is a significant cause of neonatal bacteremia, pneumonia and meningitis. Maternal recto-vaginal colonization is considered as an established risk factor for neonatal sepsis within first 7 days of life. One of the major causes of early onset of neonatal sepsis is vertical transmission of GBS from mother to their newborns. Up to 50% cases, maternal genitourinary tracts can be colonized with GBS. However, vertical acquisition of GBS occurs in 15% to 50% of newborns born to GBS colonized mothers. Invasive disease can be developed in 1-2% of newborns colonized by GBS. The etiology of neonatal infections in developing countries, the risk factors associated with them, and their modes of transmission remain poorly understood, delaying the development of effective interventions to prevent and treat neonatal infections. In the proposed study, we plan to focus on intrapartum maternal colonization with GBS as a potential source of early-onset neonatal infection


We are conducting a cohort study at Kumudini Women Medical College & Hospital, which averages 180 deliveries per month, and provides tertiary health care services to underserved urban communities. We are enrolling women who are enrolled in any other studies, attend Kumudini Hospital for antenatal care visits at 30 gestational weeks or later, plan to deliver at the Kumudini Hospital and remain in Mirzapur area after delivery. We are excluding women with co-morbid conditions (obstructed labor, hemorrhage, or severe pre-eclampsia) and who consumed antibiotics or steroids within two weeks prior to enrollment or within two weeks prior to labor and delivery. We are also excluding newborns who are born via caesarean section and have surgical conditions requiring urgent care. Newborns are examined before discharge from the hospital and at home during day 3, 7 & 28 of their lives by community health workers who assess the newborns for sickness and refer to hospital.

The primary outcome measure is clinician’s diagnosis of very severe disease following the World Health Organization Integrated Management of Childhood Illnesses criteria. A secondary outcome measure is neonatal sepsis confirmed by blood culture. We are collecting one vaginal swab and one rectal swab at the antenatal care visit after enrollment and again prior to delivery to measure maternal vaginal or rectal colonization. We are also collecting one rectal, one umbilical and one nasal swab from neonate immediately after birth. We transport all swabs at Amies transport medium daily and cultured them within 24 hours of collection for aerobic and microaerophilic gram negative and positive bacteria. All the isolates is indentified and serotyped following the standard procedure. Newborns with one or more clinical signs or symptoms of infection present on clinician exam will receive an infectious work-up including a complete blood count and differential, as well as a blood culture.