ACOG guideline update linked to drop in neonatal GBS cases and deaths

ACOG guideline update linked to drop in neonatal GBS cases and deaths | Image Credit: © Chansom Pantip - © Chansom Pantip - stock.adobe.com.

Reports of neonatal group B streptococcus (GBS) early-onset disease and deaths have declines among US patients following updates to the American College of Obstetricians and Gynecologists (ACOG) guidelines in 2019, according to a recent study published in O&G Open.¹

The 2019 guidelines recommended that screening shift from between 35- and 37-weeks’ gestation to between 36-and 37-weeks’ gestation. This change allows more accurate test results up to 41-weeks’ gestation to be provided, as screening results become less accurate when performed over 5 weeks before birth.

“The ACOG guideline change was intended to reduce discrepancies between antepartum screening results and newborn colonization status,” wrote investigators.

Key change in screening timing

To determine the difference in neonatal GBS early-onset disease and death rates before and after the guidelines updates, investigators conducted a population-based retrospective cohort study using CDC Active Bacterial Core surveillance data. The prechange period was defined as 2016 to 2018 and the postchange period as 2020 to 2022.

Investigators defined early-onset GBS as invasive GBS disease within 7 days after birth, including sepsis, pneumonia, and meningitis. Disease incidence was reported per 1000 births, with mean absolute numbers of cases and deaths measured before and after the guideline change. Data from 2019 was excluded from the analysis.

Joinpoint regression software was used to calculate the annual percent change (APC) in GBS early-onset disease incidence and deaths per 1000 births. Comparisons based on race were performed in the secondary analysis, with race categories including Black, White, and Other.

Declines in GBS cases and deaths

Neonatal GBS early-onset disease and death were reported in 2640 neonates during the prechange period and 2120 in the postchange period, with means of 0.24±0.01 and 0.20±0.02 cases per 1000 births, respectively. An APC of 2.1% was reported during the prechange period, but -9.6% in the postchange period, indicating a sharp decline.

A decrease in APC during the postchange period was reported in all race categories during the secondary analysis. However, Black patients presented with a significant decline in APC during both the prechange and postchange periods.

Limitations of the study include being unable to identify a cause-and-effect relationship and being unable to measure health care providers’ compliance with the guidance. Overall, the data highlighted a decline in neonatal GBS early-onset disease and deaths following the updated ACOG guidelines.

“The temporal relationship between the 2019 ACOG revised prenatal GBS screening guidance in the United States and the declines in incidence of neonatal GBS early-onset disease and deaths in the postchange period are reassuring and support current practice,” wrote investigators.

The broader risk of GBS in pregnancy

The risks of neonatal GBS have been highlighted by Cedars Sinai, indicating seizure as a potential outcome.² GBS presents in approximately 1 in 4 pregnant women and may pass on to their offspring, with risk factors including preterm labor, premature rupture of membranes, fever, prior pregnancy with offspring GBS, and GBS in urine.

Infants with GBS are often transferred to the neonatal intensive care unit and given intravenous (IV) antibiotics. However, other treatments may be needed in those with severe infections or presenting with meningitis or pneumonia.

Cedars Sinai stressed the importance of GBS screening during pregnancy to prevent poor outcomes. Pregnant women testing positive for GBS may receive IV antibiotics during labor, reducing the risk of infection in offspring.

References

1. Devabhaktuni A, Silverman NS, Bastian IN, Turrentine MA. Trends in perinatal group B streptococcal disease after updated screening recommendations in the United States. O&G Open 2025;2(4). doi:10.1097/og9.0000000000000094
2. Group B streptococcus infection in babies. Cedars Sinai. Accessed August 7, 2025. https://www.cedars-sinai.org/health-library/diseases-and-conditions---pediatrics/g/group-b-streptococcus-infection-in-newborns.html.