A study of pregnant women with chlamydia, a sexually transmitted disease, shows that the antibiotic azithromycin is highly effective with no significant adverse effects on mother or infant, physicians at the University of California at San Francisco report.

Dr. Lisa Rahangdale and colleagues took a look back at 227 pregnant women with genital chlamydial infection. Most of the women (69 percent) received treatment with azithromycin; 19 percent and 9 percent received two other antibiotics - erythromycin and amoxicillin, respectively. The remaining women received other drug regimens.

Treatment efficacy was 97 percent in the azithromycin group, 64 percent in the erythromycin group and 95 percent in the amoxicillin group, as evidenced by a negative test of cure 7 or more days after diagnosis and again before delivery.

Efficacy did not vary by age, ethnicity (more than half of patients were black and Hispanic) the presence of another sexually transmitted disease, partner’s treatment or substance use.

There was no difference in rates of adverse events among the treatment groups in either women or their infants.

“Considering the serious consequences of preterm labor and perinatal infection, it is important to treat pregnant women with the most efficacious regimen in pregnancy,” the authors write in the journal Sexually Transmitted Diseases.

Based on their findings, they conclude that “azithromycin should be considered as a first-line agent for the treatment of chlamydia during pregnancy.”

SOURCE: Sexually Transmitted Diseases, February 2006.