Group B Strep in Pregnancy
The short answer
Group B Streptococcus (GBS) is a common bacterium found in about 25% of healthy women. Being GBS-positive is not an infection or STI - it simply means the bacteria are present in your body. With standard intravenous antibiotics given during labor, the risk of transmitting GBS to your baby drops from about 1 in 200 to about 1 in 4,000, making outcomes excellent.
By Age
What to expect by age
GBS screening is not typically done in the first trimester because colonization status can change throughout pregnancy. If you had a previous baby affected by GBS disease, your provider should be aware early so they can plan prophylactic antibiotics during labor regardless of your screening result later.
GBS screening is not routinely performed in the second trimester either. However, if GBS is found incidentally in a urine culture at any point during pregnancy (GBS bacteriuria), you will automatically receive antibiotics during labor. GBS in urine indicates heavy colonization and does not need to be re-screened later.
Universal GBS screening is recommended between 36-37 weeks of pregnancy through a simple vaginal and rectal swab. Results are available within a few days. If you test positive, you will receive IV penicillin or an alternative antibiotic during labor, ideally at least 4 hours before delivery. This is the standard of care and is highly effective at preventing early-onset GBS disease in newborns.
If you received appropriate antibiotics during labor, your baby will be observed for the standard period after birth. If antibiotics were not given or given less than 4 hours before delivery, your baby may be monitored more closely for 24-48 hours for signs of infection such as fever, poor feeding, irritability, or breathing difficulties. Early-onset GBS disease in newborns is treatable with antibiotics.
What Should You Do?
When to take action
- You tested GBS-positive at 36-37 weeks - this is a common finding in healthy women
- You received antibiotics during labor and your baby shows no signs of infection after delivery
- You tested GBS-negative and your provider confirms no prophylaxis is needed
- You had GBS in a previous pregnancy but tested negative this time (colonization can vary between pregnancies)
- You tested GBS-positive and are unsure about your labor antibiotic plan, especially if you have a penicillin allergy
- Your labor is progressing very quickly and you are concerned about receiving antibiotics in time
- You had a previous baby with GBS disease or a previous positive GBS urine culture
- Your newborn develops fever, poor feeding, extreme sleepiness, difficulty breathing, or irritability in the first week of life
- Your water breaks before 37 weeks and you know you are GBS-positive or your status is unknown
Sources
Related Resources
Related Medical Concerns
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.
Air Quality and Baby Health
Babies and young children are more vulnerable to air pollution than adults because they breathe faster, their lungs are still developing, and they spend more time close to the ground where some pollutants concentrate. The EPA recommends keeping babies indoors when the Air Quality Index (AQI) exceeds 100 (orange level). During wildfire smoke events, keep windows closed, use air purifiers with HEPA filters, and monitor your child for coughing, wheezing, or difficulty breathing. Long-term exposure to air pollution can affect lung development.
Altitude Sickness in Babies
Babies and toddlers can experience altitude sickness when traveling above 5,000-8,000 feet (1,500-2,500 meters). Symptoms are harder to recognize in infants because they cannot describe how they feel. Watch for unusual fussiness, poor feeding, disrupted sleep, vomiting, and fast breathing. Gradual ascent is the best prevention. Most pediatricians recommend avoiding sleeping at very high altitudes (above 8,000 feet) with infants when possible, and descending immediately if symptoms appear.
Amblyopia (Lazy Eye) Treatment Timing
Amblyopia (lazy eye) is the most common cause of vision loss in children, affecting 2-3% of the population. It occurs when one eye develops weaker vision because the brain favors the other eye. Early detection and treatment are critical because the visual system is most responsive to treatment during early childhood. Treatment is most effective when started before age 7, though improvement is possible at older ages. Treatment options include patching the stronger eye, atropine eye drops, glasses, or a combination.