Researchers, led by Lori Newman from the World Health Organization, estimate that in 2008, 1.4 million pregnant women around the world were infected with syphilis, 80% of whom had attended antenatal care services.

The researchers reached this figure by using information on the number of syphilis infections from 97 countries and on antenatal clinic attendance from 147 countries and then inputting this information into a model.

In consultation with experts, the authors used a realistic scenario to estimate the percentage of pregnant women tested for syphilis and adequately treated, ranging from 30% for Africa and the Mediterranean region to 70% for Europe. Based on this scenario, the authors estimate that in 2008, syphilis infections in pregnant women caused approximately 520,000 harmful outcomes, including 215,000 stillbirths, 90,000 neonatal (baby) deaths, 65,000 preterm or low birth-weight babies, and 150,000 babies with congenital infections.

The authors estimate that in 2008, testing and treating pregnant women for syphilis prevented a quarter of such harmful outcomes but worryingly, the authors found that about two-thirds of these harmful effects occurred in women who had attended antenatal care but were not treated or tested for syphilis.

The authors say: "This analysis indicates that syphilis continues to be an important cause of adverse outcomes of pregnancy, including substantial numbers of perinatal deaths and disabilities."

They continue: "Countries also need to ensure that quality-assured syphilis testing is available in all antenatal clinic settings, now possible even in remote care settings with the introduction of rapid point-of-care diagnostics."

The authors add: "In addition, efforts are needed to ensure universal access to early antenatal care, as well as improved quality of antenatal care so that all pregnant women receive an essential package of services that includes routine and early access to point-of-care testing and adequate treatment for syphilis if seropositive."