Group B Strep (GBS) Infection in Newborns
The short answer
Group B Streptococcus (GBS) is a bacterium that some mothers carry and can pass to their baby during delivery. When mothers who test positive receive antibiotics during labor, the risk to the baby is greatly reduced. GBS infection in newborns can be serious, causing sepsis, pneumonia, or meningitis, but with prevention measures and prompt treatment, most babies do well.
Parents everywhere have the same worry. You are doing the right thing by looking into it.
By Age
What to expect by age
Early-onset GBS disease occurs within the first week of life (usually within 24-48 hours) and is acquired during passage through the birth canal. Prevention through maternal antibiotic treatment during labor has dramatically reduced early-onset GBS disease. If your baby was born to a GBS-positive mother who received adequate antibiotics during labor, the risk is very low. Babies born to GBS-positive mothers who did not receive adequate antibiotics, or who show any signs of illness, are monitored closely and may receive empiric antibiotics. Late-onset GBS disease (1 week to 3 months) can occur from maternal or environmental sources.
Late-onset GBS disease can occur during this period. Signs include fever, irritability, poor feeding, and lethargy. Late-onset GBS can cause meningitis, bloodstream infection, or bone/joint infection. Any fever in a baby under 3 months requires emergency evaluation, which includes testing for GBS among other bacterial causes.
GBS infection becomes very rare after 3 months of age. Babies who had GBS infections that were treated promptly typically recover fully. Those who had GBS meningitis may need developmental follow-up.
GBS infection risk is negligible at this age. Babies who recovered from GBS infection in the newborn period should have normal development, though those who had meningitis may need monitoring for hearing and developmental milestones.
What Should You Do?
When to take action
- Mother was GBS positive, received adequate antibiotics during labor, and baby has been well since birth
- Baby was observed for the recommended period after birth and showed no signs of infection
- Baby is feeding well, maintaining normal temperature, and is alert and active
- You were GBS positive and are unsure if you received adequate antibiotics during labor
- Your baby seems slightly unwell in the first few days after birth
- You have questions about GBS prevention for future pregnancies
- Any fever, poor feeding, lethargy, rapid breathing, or unusual irritability in a newborn, especially if born to a GBS-positive mother or if maternal antibiotic treatment was incomplete
- Signs of infection at any point in the first 3 months of life
Sources
Related Resources
Trust your instincts. If something feels wrong, reach out to your pediatrician.
Worrying about your baby means you care. That is a good thing.
Related Medical Concerns
Signs of Infection and Sepsis in Newborns
Neonatal sepsis is a serious bacterial infection in the bloodstream that can develop in the first month of life. Signs are often subtle and can include temperature instability, poor feeding, lethargy, irritability, rapid breathing, and a "just not right" appearance. Neonatal sepsis is a medical emergency requiring immediate antibiotics. Trust your instincts if your newborn seems unwell.
Fever in a Baby Under 3 Months Old
A fever in a baby under 3 months old (temperature of 100.4 degrees F / 38 degrees C or higher taken rectally) is always a medical emergency. Go to the emergency room immediately, regardless of how well your baby appears. Young babies' immune systems cannot fight infections as effectively as older children, and a fever could indicate a serious bacterial infection (urinary tract infection, bacteremia, or meningitis) that needs urgent treatment. Do NOT wait to see if the fever goes down. Do NOT give fever medication and stay home - go to the ER first.
My Baby's Head Shape Looks Abnormal
Many babies develop temporary head shape irregularities that are completely normal. A cone-shaped head from vaginal delivery reshapes within days. Mild positional flattening (plagiocephaly) from sleeping on the back is very common and usually improves with repositioning and tummy time. However, head shape changes involving ridges, a persistently bulging fontanelle, or rapid head growth changes should be evaluated to rule out craniosynostosis.
Achondroplasia (Dwarfism) in Babies
Achondroplasia is the most common form of short-limbed dwarfism, affecting about 1 in 15,000 to 40,000 births. It is caused by a mutation in the FGFR3 gene and is usually apparent at birth with characteristic features including short limbs, a larger head, and a prominent forehead. Intelligence is normal. With monitoring for specific complications and supportive care, children with achondroplasia lead full, active, and independent lives.
Adenoid Hypertrophy and Breathing
Adenoids are lymphoid tissue located behind the nose that help fight infection in young children. When adenoids become enlarged (adenoid hypertrophy), they can block the nasal airway, causing chronic mouth breathing, snoring, nasal speech, and sleep-disordered breathing. Enlarged adenoids are most common between ages 2-7 and are a leading cause of obstructive sleep apnea in young children. Treatment ranges from watchful waiting and nasal steroids to surgical removal (adenoidectomy) if breathing or sleep is significantly affected.
How to Advocate for Your Child's Needs
You know your child better than anyone, and your observations matter. If you feel something is not right with your child's development or health, you have every right to ask questions, request evaluations, and seek second opinions. Advocating for your child is not being difficult - it is being a good parent.