Congenital Syphilis in Texas Section 7 - Birth Outcomes Associated with Congenital Syphilis

A pregnant woman diagnosed with syphilis can transmit syphilis to her unborn child. A probable CS case most often includes a child whose mother had untreated or inadequately treated syphilis at the time of delivery. Probable CS cases can be identified through infants with reactive non-treponemal blood tests AND one of the following: evidence of CS on physical exam, long-bone x-ray, reactive cerebrospinal fluid (CSF) venereal disease research laboratory (VDRL) test, or elevated CSF white blood cell count or protein count without other cause.

A syphilitic stillbirth is classified as a birth to a woman with untreated or inadequately treated syphilis who delivered at least 20 weeks’ gestation, or the fetus weighs at least 500 grams. A confirmed CS case is one that is confirmed through specialized laboratory testing for the presence of Treponema pallidum. CS is classified as “early” when the child exhibits symptoms at birth up to their second birthday, and “late” when symptoms start after age two. [7] Early CS symptoms can include vision or hearing loss, non-viral hepatitis causing jaundice of the skin and eyes, long bone abnormalities, developmental delays, enlargement of the liver and/or spleen, inflammation of the mucus membranes of the nose, rash, wart-like lesions on the genitals, and additional symptoms. [7] Older children may develop clinical symptoms of late congenital syphilis, including problems with bone and teeth development, problems with hearing or vision, and issues with the central nervous and cardiovascular systems. [7]

Among the 367 CS cases in 2018, approximately one-quarter had a low birth weight ( <2500g) and one-quarter were preterm (<37 weeks’ gestation). The percentage of low birth weight and preterm infants was higher in comparison to all births in Texas where 8 percent were low birth weight and 11 percent were preterm.[8] Seventeen (5 percent) of the reported CS cases resulted in a stillbirth or a neonatal death. Of the 367 infants reported with CS, there were 13 syphilitic stillbirths, two confirmed cases, and 352 probable cases.

Table 3: Birth Outcomes of CS Cases, Texas 2018


Birth Outcomes

No. of Cases


Total Cases



Birth Weight



Low Birth Weight ( <2500g)



Normal Birth Weight (≥2500g)






Gestational Age



Preterm ( <37 weeks)



Full-term (≥37 weeks)






Vital Status






Stillbirth or neonatal death



Unknown vital status






Probable Case



Syphilitic Stillbirth



Confirmed Case




Testing and Treatment for Infants with Congenital Syphilis

Treatment and evaluation decisions for infants born to mothers diagnosed with syphilis are based on maternal syphilis history, maternal treatment adequacy, and clinical and laboratory evaluation for the infant.

Per CDC treatment guidelines, all infants born to women with positive syphilis serology should have a quantitative non-treponemal lab rapid plasma reagin (RPR) or venereal disease research laboratory (VDRL) drawn at delivery. [9] Although 96 percent of CS cases were probable or confirmed and should have had a non-treponemal test, only 43 percent of CS cases had an RPR or VDRL test performed (Figure 17). Further clinical evaluations may not be necessary for all reported CS cases depending on the provider’s assessment of the infant’s CS clinical scenario. Current surveillance data does not distinguish the clinical scenario; therefore, which infants were appropriately evaluated cannot be ascertained.

Confirmatory tests (darkfield, immunohistochemistry (IHC), polymerase chain reaction (PCR), or special stains) can definitively demonstrate the presence of Treponema pallidum in body fluids or tissue and can be performed on placentas, umbilical cords, or autopsy material.[9] While only one percent of infants reported with CS had an evaluation using the confirmatory testing methodology, 100 percent of those tested had reactive results on darkfield, IHC, PCR, or special stains (Figure 18).

Figure 17. Testing and Evaluation for Infants Reported with CS, Texas 2018 
Figure 17. Testing and Evaluation for Infants Reported with CS, Texas 2018. Non-treponemal testing (RPR, VDRL). 43% Yes, 57% No/Unknown; CSF VDRL, 30% Yes, 70% No/Unknown; CSF cell count or CSF protein, 22% Yes, 78% No/Unknown; Long bone x-rays, 32% Yes, 68% No/Unknown; Darkfield, PCR, IHC, or special stain, 1% Yes, 99% No/Unknown.


Figure 18. Outcomes of Testing and Evaluation for Infants Reported with CS, Texas 2018
Figure 18. Outcomes of Testing and Evaluation for Infants Reported with CS, Texas 2018. Reactive RPR 42%, Signs of CS on exam 3%, Long bone abnormalities 4%, Reactive CSF VDRL 4%, Elevated CSF cell count or CSF protein 12%, Darkfield, PCR, IHC, or special stain 1%.


Among infants reported with CS, approximately half (about 53 percent) received treatment (Table 4).

Table 4: Treatment for Infants with CS, Texas 2018


Treatment for Infants Reported with CS

No. of Infants


Yes, Aqueous or Procaine penicillin for ≥ 10 days



Yes, with Benzathine penicillin X 1



Yes, with other treatment



No treatment










Note 7. Centers for Disease Control and Prevention, “Congenital Syphilis (Treponema pallidum) 2018 Case Definition.” [Online]. Available: Syphilis (Treponema pallidum) 2018 Case Definition | CDC

Note 8. Texas Department of State Health Services. Centers for Health Statistics. 2018 Provisional Texas Birth Certificate data.

Note 9. Centers for Disease Control and Prevention (CDC). 2021 Sexually Transmitted Diseases Treatment Guidelines. STI Treatment Guidelines (

Congenital Syphilis in Texas

Table of Contents | Executive Summary | About this Report | Understanding Syphilis | An Overview of Congenital Syphilis and Syphilis in Women of Childbearing Age in Texas | Maternal Demographics for Women Delivering Infants with Congenital Syphilis | Barriers to Care | Birth Outcomes Associated with Congenital Syphilis | Congenital Syphilis Cascade