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Oral 69 Does Cesarean section and formula feeding reduce vertical transmission in chronic hepatitis B pregnant mothers?
Author Insight from Rasham Mittal, MD, Kaiser Permanente Los Angeles Medical Center
What’s new here and important for clinicians?
About 350 million people worldwide suffer from chronic hepatitis B (CHB), a vaccine preventable liver disease. In the United States, an estimated 1.4 million individuals have CHB, leading to nearly 4,000 deaths annually. With <2% prevalence of hepatitis B surface antigen (HBsAg), roughly 24,000 CHB pregnant women give birth in United States every year (Centers for Disease Control and Prevention [CDC], unpublished data, 2004). Perinatal acquisition of hepatitis B virus (HBV) carries 85% to 95% risk of chronic infection, with 25% to 30% lifetime risk of a serious complication or fatal liver disease compared to far lower rates of chronic infection when acquired during adulthood.
Current guidelines suggest screening all pregnant women for HBsAg. This universal screening practice allows for early detection of chronic HBV pregnant mothers whose infants should receive recommended immunoprophylaxis with both hepatitis B vaccine and hepatitis B immunoglobulin (HBIG). This approach has significantly reduced the HBV vertical transmission rate from 70-90% to 5-10%, which is confirmed by infants’ HBsAg testing at 9-18 months following birth.
However, the mechanism of mother-to-child transmission (MTCT) remains unclear and still occurs after passive active immunization. This concern has garnered an ever-growing interest for new measures aimed at reducing vertical transmission. Some of these measures include use of antiretroviral drugs during second or third trimester of pregnancy, and encouraging Caesarean section and formula feeding for CHB pregnant mothers and their infants respectively.
The mode of delivery and infant feeding in chronic hepatitis B (CHB) mothers has been controversial subject for decades. Currently, there is no preferred mode of delivery in CHB pregnant mothers. Studies investigating the role of Caesarean section over normal vaginal delivery in preventing viral transmission have been carried out. Also, no additional risk of perinatal viral transmission has been found with breastfeeding. The American Academy of Pediatrics supports breastfeeding as long as the infant has received HBIG and hepatitis B vaccine. Limited pertinent data is available from United States for this cohort.
The aims of study were to investigate the effect of C-section and formula feeding on vertical transmission in a cohort of CHB pregnant mothers from United States at a large integrated health care system across Southern California.
NVD vs. C-Section Findings
MTCT occurred only in one infant (delivered vaginally) with vertical transmission rate being 0.3%. No statistically significant difference found for risk of transmission between CHB mothers with NVD vs. C-Section (1/196 vs. 0/92, P>0.5)
Compared HBeAg positive mothers with NVD and HBeAg positive patients with C-Section, no statistically significant reduction in MTCT rate observed (1/26 vs. 0/8; P> 0.5).MTCT occurred only in one infant who was breast-fed
No statistically significant difference found for risk of transmission between CHB mothers who breastfed vs. formula feeding (1/248 vs. 0/34, P>0.5).
Compared HBeAg positive mothers who breastfed versus formula fed their infants, no statistically significant reduction in MTCT rate observed (1/29 vs. 0/5; P> 0.5).
What do patients need to know?
With the recommended immunoprophylaxis against hepatitis B, C-section and formula feeding do not reduce vertical transmission risk.
Author Contact Rasham Mittal, MD, Kaiser Permanente Los Angeles Medical Center
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