Preventing the Rise in Congenital Syphilis

Parents looking at ultrasound photo
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In 2007, after 14 years of decline in the United States, the rate of congenital syphilis once again went up. After that increase hit the news things improved for a while. However, starting in 2012, rates began to rise again. Over the next two years, the number of babies born with syphilis increased around the country. That is a dangerous trend, but one that can be monitored and potentially prevented.

Congenital Syphilis Basics

Congenital syphilis occurs when a mother who has syphilis during pregnancy transmits the disease to her growing fetus. In other words, it is a condition that a growing fetus acquires in the womb. Its consequences can range from mild to severe.

Ideally, all women should get screened for syphilis during pregnancy as part of routine prenatal care. However, not all women get adequate and appropriate prenatal care. Furthermore, even those who do may not be screened or treated appropriately.

In addition, sometimes testing goes as planned but life doesn't. If a woman becomes infected with syphilis after she has already been tested, the infection may be missed. That gives a window for infection to be transmitted to her child. A pregnancy is also at higher risk when syphilis treatment starts less than 30 days before delivery and when the wrong treatment is used.

How Congenital Syphilis Impacts Children

In those children that were affected:

  • 6.5 percent of infants died before 12 months of age, 82 percent of those were stillborn. This means they passed away before birth.
  • 34 percent had serious physical side effects of infection.

Despite these shocking statistics, remember that congenital syphilis is more likely to be fatal when an infected mother is not appropriately treated.

Fatalities are also more likely in women who have less prenatal care or when an infant is born very small or before 28 weeks. 


Congenital syphilis can be somewhat difficult to diagnose in an infant. The standard diagnostic test for syphilis is based on a blood test that looks for antibodies to the syphilis bacterium. That test is unreliable in infants, as those antibodies can be transmitted from the mother to the child. Therefore, when congenital syphilis is suspected, doctors must use a somewhat complicated protocol to try to determine whether or not a child is actually infected.

This can include looking for signs of infection in the child's cerebrospinal fluid (CSF). It can also include looking for other signs of syphilis infection in the organs of the body. To some degree, diagnosis of congenital syphilis is an art as well as a science. It may require repeated testing and judgment calls.


Penicillin G is used as a treatment in infants with congenital syphilis. The specific regimen will depend on both maternal and infant test results and specific signs of disease. For infants whose infection is clear, medication is usually given in one of two ways: either intramuscular injections of procaine penicillin G are given daily or intravenous aqueous crystalline penicillin G is given multiple times a day for 10 days.

Rigorous and reliable treatment is very important. The entire treatment needs to be started over if more than 24 hours of medication are missed. When infection is less likely due to the mother being appropriately treated, a single injection may be given instead of the longer course.

Infants still need to be checked regularly even after treatment is completed. This is particularly true when problems are seen in an infant's CSF. Doctors recommend that infants with any abnormal CSF test be retested with a lumbar puncture every 6 months until results are normal.

Congenital Syphilis Can Be Prevented

Good prenatal care is an important first line of defense against congenital syphilis.

The CDC recommends that all women be screened for syphilis at their first prenatal visit. It is also suggested that women at high risk of congenital syphilis be screened again at 28 weeks. Any positive test should lead to treatment with Benzathine penicillin G—the only form of treatment known to be effective at preventing congenital syphilis.

Screening during prenatal care isn't the only method of prevention. Consistently practicing safe sex during pregnancy is a good idea any time you are not in a mutually monogamous relationship, one where both people have been tested. Similarly, it is good for the pregnant person's sexual partner(s) to get screened for STDs. That way they can be treated, if appropriate.

If someone is diagnosed with syphilis during pregnancy, all sexual partners should be screened and treated as well. This reduces the risk of re-infection. Unfortunately, this is not always easy to accomplish. Sometimes it's hard to locate all partners or convince them to come in for treatment. That's another reason why safe sex is a good idea.

And remember, syphilis isn't the only STD that can have negative effects on a pregnancy, so testing for other STDs is also important.


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