Syphilis and pregnancy

Last updated April 19, 2024

pregnant women in group

Syphilis in newborns is known as congenital syphilis. Congenital syphilis happens when untreated syphilis passes to a fetus during pregnancy.

Congenital syphilis can lead to miscarriage, stillbirth, preterm delivery, long-term medical conditions, and even infant death. Some babies with syphilis can be healthy at birth, but develop serious complications later in life. 


Congenital syphilis is increasing in Colorado

Graph showing an increase in rates of congenital syphilis from three cases in 2003 to 50 cases in 2023.

From 2018 to 2023, congenital syphilis cases increased more than seven times in Colorado (seven cases in 2018 to 50 cases in 2023).


Data from 2023 is preliminary. Additional data will be available when it is finalized. For questions about syphilis data, use CDPHE’s data request form.


What can I do to protect myself and my baby?

  • Make sure to request a comprehensive sexually transmitted infection (STI) test panel screening at your first prenatal visit. This panel includes syphilis testing.
  • If you test positive for syphilis, get treatment right away.
  • If you are pregnant and have syphilis, you can still reduce the risks of passing syphilis to your baby. Getting tested and treated for syphilis can prevent serious health complications for both you and your baby.
  • Prenatal care is essential to the overall health and wellness of you and your child. The sooner you begin receiving medical care during pregnancy, the better the health outcomes will be for you and your baby.
  • Talk to your partner(s) about getting tested. If your partner has syphilis, you could get infected or reinfected, even if you have already been treated for syphilis.
  • Use condoms during sexual intercourse.
  • Remember that it’s possible to get syphilis and not know it. Sometimes the infection causes no symptoms, only very mild symptoms, or symptoms that look like other illnesses.
  • Talk with your doctor about your risk for syphilis. Have an open and honest conversation about your sexual history and STI testing. Your doctor can give you the best advice on any testing and treatment that you may need. 

Syphilis testing and the law

Colorado law requires health care providers to offer syphilis testing to anyone who is pregnant.

Starting April 25, 2024, all healthcare facilities, like hospitals, urgent care clinics, community health clinics, emergency departments, and other medical offices, must provide services to stop the spread of syphilis in the state, particularly among those who are pregnant.

Public Health Order 24-01 requires all health care settings and medical providers who care for anyone who is pregnant to offer syphilis testing:

  • In the first trimester of pregnancy (between 1-12 weeks), or at the patient’s first prenatal visit. 
  • In the third trimester (between 28-32 weeks). 
  • At the time of delivery. 
  • If there's a miscarriage after 20 weeks or stillbirth. 
  • When a patient who is pregnant goes to an urgent care center or emergency room, at the intervals and events described above. 
  • At correctional facilities, including prisons, jails, and juvenile detention centers, at the intervals and events described above.

Treatment for syphilis in pregnancy

Those who are pregnant and have a syphilis diagnosis should seek treatment as soon as possible to prevent serious complications to their baby. Long-acting benzathine penicillin G therapy must be used to treat syphilis during pregnancy to prevent syphilis transmission to the baby. This therapy is extremely effective in preventing congenital syphilis, with a success rate of up to 98%. People who are allergic to penicillin should see a specialist for desensitization.

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