Black women, health care workers, and overweight women are at increased risk for carrying group B streptococcus (GBS) during pregnancy, new research suggests.
GBS is a microbe that can live in or “colonize” the birth canal and then be passed onto the infant during birth, resulting in a potentially life-threatening infection.
Better knowledge of factors that increase the risk of GBS colonization in pregnancy could help efforts to prevent or treat the infection and thus protect infants from serious complications, Dr. Renee D. Stapleton of the University of Washington School of Medicine in Seattle and colleagues write in the journal Obstetrics & Gynecology.
Stapleton and her colleagues performed a population-based study that included 40,459 cases of GBS colonization drawn from birth certificate information and hospital discharge data. These cases were matched by year of delivery to 84,268 comparison subjects.
Women in health care occupations with a high frequency of direct patient contact faced a 22 percent increased risk of GBS colonization, the researchers found, while black women’s risk was 54 percent greater.
Being overweight increased risk by 7 percent, while obesity increased it by 20 percent and severely obese women were at a 45 percent greater risk.
Women with the highest incomes, more education and adequate prenatal care also were shown to be at increased risk of GBS, the researchers note, although this may have been because they were more likely to have obtained prenatal care that included GBS screening, a so-called “detection bias.”
Smokers and Hispanic women were at slightly decreased risk for GBS colonization. Unlike previous research, the researchers found no relationship between diabetes during or before pregnancy and GBS risk.
There was no relationship between health care occupation and GBS risk among women who had minimal patient contact, suggesting that patient contact itself could be the exposure route, Stapleton and her team note. Further investigation of this relationship and other risk factors identified by the study is needed, they conclude, because the cause behind them is still not clear.