What is the indication for intrapartum Group B Streptococcus (GBS) prophylaxis in a 23-year-old woman, gravida 2, para 1, at 37 weeks gestation with a history of prior term vaginal delivery complicated by intraamniotic infection and early-onset neonatal sepsis?

From the Guidelines

The indication for intrapartum group B Streptococcus (GBS) prophylaxis in this patient is her unknown GBS status at the time of labor, as well as her previous infant with invasive GBS disease, which is a clear indication for prophylaxis according to the CDC guidelines 1.

Patient's History and Current Status

The patient's history of a previous pregnancy complicated by intraamniotic infection and an infant with early-onset neonatal sepsis further supports the need for prophylaxis.

• The patient had routine prenatal care only until 20 weeks gestation and has not had appointments since then, likely missing the standard GBS screening that typically occurs between 36-37 weeks.
• Her current status includes grossly ruptured membranes with clear fluid, and the cervix is 3 cm dilated and 30% effaced with the fetal vertex at −1 station.

Recommended Regimen

The recommended regimen for intrapartum GBS prophylaxis would be intravenous penicillin G with an initial dose of 5 million units, followed by 2.5-3 million units every 4 hours until delivery, as outlined in the CDC guidelines 1.

• For patients with penicillin allergy without anaphylaxis risk, cefazolin 2g IV initially, then 1g every 8 hours is appropriate.
• For those with severe penicillin allergy, clindamycin 900mg IV every 8 hours or vancomycin 20mg/kg IV every 8 hours (if GBS is resistant to clindamycin) would be indicated.

Importance of GBS Prophylaxis

GBS prophylaxis is crucial because GBS colonization occurs in 10-30% of pregnant women, and vertical transmission can lead to serious neonatal infections including pneumonia, sepsis, and meningitis.

• Without adequate screening results, prophylaxis is the safest approach to prevent potential neonatal GBS disease.
• The CDC guidelines emphasize the importance of intrapartum antibiotic prophylaxis for the prevention of early-onset group B streptococcal disease, and this patient's history and current status align with the indications for such prophylaxis 1.

From the Research

Indication for Intrapartum Group B Streptococcus (GBS) Prophylaxis

The patient's history and current situation indicate several factors that are relevant to determining the need for intrapartum GBS prophylaxis. Key points include:

• Prior pregnancy complicated by intraamniotic infection and the infant having early-onset neonatal sepsis
• Current gestation at 37 weeks with ruptured membranes and clear fluid
• The patient's temperature, blood pressure, and pulse are within normal limits
• Leukocyte count is slightly elevated at 13,000/mm3

Relevant Guidelines and Studies

According to the studies provided:

• The American Academy of Pediatrics and the American College of Obstetricians and Gynecologists recommend intrapartum antibiotic prophylaxis for pregnant women with a history of GBS colonization, especially if other risk factors are present 2, 3.
• Risk factors for neonatal GBS infection include preterm delivery, maternal fever during delivery, and prolonged rupture of membranes 4, 5.
• The optimal window for screening for GBS colonization is between 36 0/7 and 37 6/7 weeks of gestation 2, 3.
• Intrapartum antibiotic prophylaxis is effective in preventing GBS early-onset disease, and penicillin, ampicillin, or cefazolin are recommended for prophylaxis 2, 4.

Application to the Patient's Situation

Given the patient's history of a prior pregnancy complicated by intraamniotic infection and early-onset neonatal sepsis, and considering her current situation with ruptured membranes at 37 weeks gestation, the indication for intrapartum GBS prophylaxis is based on her risk factors and the guidelines provided. The patient's elevated leukocyte count may also be a consideration, although it is not explicitly mentioned as a standalone indicator for GBS prophylaxis in the provided studies.

Key Points for Decision Making

• History of intraamniotic infection and neonatal sepsis in a previous pregnancy
• Current pregnancy at 37 weeks with ruptured membranes
• Elevated leukocyte count
• Guidelines recommending intrapartum antibiotic prophylaxis for women with GBS colonization and other risk factors 2, 4, 5, 3
• The importance of identifying and managing risk factors for GBS transmission to the newborn 2, 3