Risk Factors for Perinatal Transmission of Hepatitis C Virus.

OBJECTIVE: To estimate the rate of perinatal transmission of hepatitis C virus (HCV) infection, to identify risk factors for perinatal transmission of HCV infection, and to determine the viremic threshold for perinatal transmission. METHODS: This was a prospective, multicenter, observational study of pregnant individuals at less than 24 weeks of gestation screened for HCV infection from 2012 to 2018 in the Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network. Individuals found to be HCV antibody-positive were followed throughout pregnancy. Children were followed for evidence of perinatal transmission at 2-6 months (HCV RNA testing) and at 18-24 months (HCV RNA and antibody testing) of life. The primary outcome was perinatal transmission, defined as positive test results at either follow-up time point. RESULTS: A total of 109,379 individuals were screened for HCV infection. Of the 1,224 participants who screened positive, 772 (63.1%) enrolled and 432 of those 772 (56.0%) had data available to assess primary outcome. The overall rate of perinatal transmission was 6.0% (26/432, 95% CI 4.0-8.7%). All children with HCV infection were born to individuals with demonstrable viremia. In viremic participants (n=314), the perinatal transmission rate was 8.0% (95% CI 5.2-11.5%). Risk factors for perinatal transmission included HCV RNA greater than 106 international units/mL (adjusted odds ratio [aOR] 8.22, 95% CI 3.16-21.4) and vaginal bleeding reported at any time before delivery (aOR 3.26, 95% CI 1.32-8.03). A viremic threshold for perinatal transmission could not be established. CONCLUSION: Perinatal transmission of HCV infection was limited to viremic individuals. High viral loads and antepartum bleeding were associated with perinatal transmission.

Racial and ethnic disparities in maternal morbidity and obstetric care.

OBJECTIVE: To evaluate whether racial and ethnic disparities exist in obstetric care and adverse outcomes. METHODS: We analyzed data from a cohort of women who delivered at 25 hospitals across the United States over a 3-year period. Race and ethnicity was categorized as non-Hispanic white, non-Hispanic black, Hispanic, or Asian. Associations between race and ethnicity and severe postpartum hemorrhage, peripartum infection, and severe perineal laceration at spontaneous vaginal delivery as well as between race and ethnicity and obstetric care (eg, episiotomy) relevant to the adverse outcomes were estimated by univariable analysis and multivariable logistic regression. RESULTS: Of 115,502 studied women, 95% were classified by one of the race and ethnicity categories. Non-Hispanic white women were significantly less likely to experience severe postpartum hemorrhage (1.6% non-Hispanic white compared with 3.0% non-Hispanic black compared with 3.1% Hispanic compared with 2.2% Asian) and peripartum infection (4.1% non-Hispanic white compared with 4.9% non-Hispanic black compared with 6.4% Hispanic compared with 6.2% Asian) than others (P<.001 for both). Severe perineal laceration at spontaneous vaginal delivery was significantly more likely in Asian women (2.5% non-Hispanic white compared with 1.2% non-Hispanic black compared with 1.5% Hispanic compared with 5.5% Asian; P<.001). These disparities persisted in multivariable analysis. Many types of obstetric care examined also were significantly different according to race and ethnicity in both univariable and multivariable analysis. There were no significant interactions between race and ethnicity and hospital of delivery. CONCLUSION: Racial and ethnic disparities exist for multiple adverse obstetric outcomes and types of obstetric care and do not appear to be explained by differences in patient characteristics or by delivery hospital. LEVEL OF EVIDENCE: II.