The number of pregnancies affected by the sexually transmitted infection syphilis is at a 20-year high in the U.S. , according to a new report from the U.S. Centers for Disease Control and Prevention. That indicates a serious breakdown in prenatal care delivery to the most vulnerable women in the U.S.

The effects of congenital syphilis on fetus and infant health are catastrophic and have lifelong consequences for children who contract it in utero.

An estimated 40 percent of pregnancies affected by syphilis end either in stillbirth, which is a pregnancy loss after 20 weeks of gestation, or the death of the infant soon after birth. Babies who survive infection in the womb can suffer birth defects like blindness, deafness, deformed bones and enlarged internal organs. Congenital syphilis can also cause cognitive developmental disabilities.

The number of cases of congenital syphilis is minuscule compared to the approximately 4 million births that take place in the U.S. every year. But public health experts are alarmed at the rise of congenital syphilis because the disease is completely curable with antibiotics if caught early.

The most recent national congenital syphilis rate, which was 23.3 cases per 100,000 live births in 2017, is also the highest reported in 20 years and represents a significant backslide from just a few years ago. Its a 153 percent increase relative to the 9.2 cases per 100,000 births in 2013, and rates have been steadily increasing since then.

In 2017, doctors reported 918 cases of congenital syphilis, which led to 64 stillbirths and 13 infant deaths. The majority of these cases 72 percent are concentrated in six states in the South and West: Louisiana, Nevada, California, Texas, Florida and Arizona.