Hepatitis B Testing in All Pregnancies
Changing times and the apparently increasing risk that newborn babies will contract hepatitis B from their mothers--even if the mothers are not symptomatic--is fueling an effort to screen all pregnant women for the virus, a practice not now required by any state.
Within the past several months, half a dozen studies published in medical journals--including a major one and an editorial supporting it that have just appeared--have come to the same conclusion:
Because the hepatitis B virus is apparently becoming more commonplace in pregnant women, any woman carrying a fetus should have a screening test for the disease by the 34th week of her pregnancy. The screening should include all pregnant women, not just those judged by conventional criteria to be at high risk.
The recommendation, moreover, is currently under review by a vaccination and screening policy committee of the U.S. Public Health Service and the Centers for Disease Control, which may officially call for changes in federal screening guidelines to include the test for all pregnant women by early next year. The CDC hepatitis division expects the proposal to be presented to the American College of Obstetricians and Gynecologists for concurrence in January, according to officials.
The push for universal hepatitis B screening received more support this month with publication in the Annals of Internal Medicine of a study by a research team in Cleveland and an editorial by a New York epidemiologist urging routine screening of all expectant mothers.
The Cleveland study, led by Dr. Mary Kumar, a pediatrician at Cleveland Metropolitan General Hospital, examined records of nearly 4,400 pregnant women who were screened for hepatitis. A higher proportion than expected--5.2 of each 1,000 deliveries--turned out to involve mothers who were carrying the virus and could pass it on to their babies at birth.
Newborns may develop hepatitis within weeks of birth, and even if they do not, they live their lives at high risk of contracting it. Many of the mothers were unaware they had been exposed to the virus. A person can be a hepatitis carrier and not develop the disease.
The Kumar team noted that traditional risk factor lists used to determine if a woman is likely to be a hepatitis B carrier proved unable to reliably predict which women would test positive. In a telephone interview, Kumar said there are many lower-risk populations in which the likelihood of hepatitis is probably only one or two births of every thousand.
Nevertheless, she said, “there is an increased awareness that the risk factors are just not sensitive enough to pick up all the pregnant women” with the virus. “When a baby is infected, it is infected for life. You’re talking about preventing a lifetime of being affected by this disease.”
A mother identified as positive for the virus can be treated before birth and the risk to her child can be eliminated. Writing in support of universal screening, Dr. Cladd Stevens, of the New York Blood Center, noted that “nearly all” infants who are infected by their mothers become chronic carriers of hepatitis B and that many carriers of the virus eventually develop liver cancer or cirrhosis, whether they come down with hepatitis itself or not.
The CDC’s Dr. Mark Kane said government scientists believe the current recommendation that hepatitis treatment should begin within 12 hours after birth, where necessary, is inadequate to the threat posed by hepatitis B and that the policy should be revised.
