Subscribe to RSS
DOI: 10.1055/a-2663-5613
Incidence and Characteristics of Infants with Congenital Syphilis in U.S. NICUs from 2011 to 2020
Funding None.

Abstract
Objective
Congenital syphilis presents a significant public health problem. Since 2012, there has been a dramatic increase in reported cases of congenital syphilis. However, characteristics of these cases have not been well detailed. This study sought to describe recent trends in the incidence of congenital syphilis, demographic characteristics, hospital treatment, and outcomes of these infants.
Study Design
A retrospective cohort study of all infants in the Pediatrix Clinical Data Warehouse (CDW; a large multicenter de-identified dataset) from 2011 to 2020 was performed. We identified infants with a diagnosis of congenital syphilis and evaluated trends in overall prevalence, as well as changes in maternal and infant characteristics over time.
Results
Of 842,928 infants discharged over the study period, we identified 1,625 infants with congenital syphilis. Between 2011 and 2020, the prevalence of congenital syphilis increased from 0.8 to 4.6 per 1,000 neonatal intensive care unit (NICU) admissions (p < 0.05). Most infants were treated with penicillin for 10 days, and the median length of stay was 10 days. Mortality was 0.9% in this cohort. Maternal coinfection with Hepatitis C was unchanged but remained significantly above national rates of Hepatitis C infection in pregnant women. Maternal drug use in infants born with congenital syphilis increased from 6.1 to 24.6% over the decade of the study. The distribution of maternal race changed over the decade, with significantly more mothers identified as White or Other in 2019 to 2020 as compared to the earlier cohorts. There was a concurrent decrease in mothers who identified as Hispanic or African American.
Conclusion
From 2011 to 2020, the prevalence of congenital syphilis in the Pediatrix CDW increased by 475%. Although infant characteristics remained similar over time, there was a notable increase in maternal drug use and a persistently elevated risk of other sexually transmitted diseases. Further research examining the association between maternal comorbidities and congenital syphilis is necessary.
Key Points
-
Between 2011 and 2020, the prevalence of congenital syphilis increased by 475%.
-
Mortality of congenital syphilis in live-borns stayed steady at 0.9%.
-
Maternal coinfection with other sexually transmitted diseases remained high over the decade.
-
Maternal drug use in infants with congenital syphilis increased significantly over the decade.
Publication History
Received: 27 February 2025
Accepted: 22 July 2025
Article published online:
07 August 2025
© 2025. Thieme. All rights reserved.
Thieme Medical Publishers, Inc.
333 Seventh Avenue, 18th Floor, New York, NY 10001, USA
-
References
- 1 Cooper JM, Sánchez PJ. Congenital syphilis. Semin Perinatol 2018; 42 (03) 176-184
- 2 Eppes CS, Stafford I, Rac M. Syphilis in pregnancy: an ongoing public health threat. Am J Obstet Gynecol 2022; 227 (06) 822-838
- 3 Stafford, IA,Workowski, KA, Bachmann, LH. Syphilis complicating pregnancy and congenital syphilis. N Engl J Med 2024; 390: 242-253
- 4 Center for Disease Control and Prevention. Congenital Syphilis. Accessed July 29, 2025 at: https://www.cdc.gov/sti-statistics/annual/summary.html
- 5 Ghanem KG, Ram S, Rice PA. The modern epidemic of syphilis. N Engl J Med 2020; 382 (09) 845-854
- 6 Spitzer AR, Ellsbury D, Clark RH. The Pediatrix BabySteps® Data Warehouse–a unique national resource for improving outcomes for neonates. Indian J Pediatr 2015; 82 (01) 71-79
- 7 Valentine JA, Bolan GA. Syphilis elimination: Lessons learned again. Sex Transm Dis 2018; 45 (9S suppl 1): S80-S85
- 8 Warren HP, Cramer R, Kidd S, Leichliter JS. State requirements for prenatal syphilis screening in the United States, 2016. Matern Child Health J 2018; 22 (09) 1227-1232
- 9 Alexander JM, Sheffield JS, Sanchez PJ, Mayfield J, Wendel Jr GD. Efficacy of treatment for syphilis in pregnancy. Obstet Gynecol 1999; 93 (01) 5-8
- 10 Kidd S, Bowen VB, Torrone EA, Bolan G. Use of National Syphilis Surveillance Data to develop a congenital syphilis prevention cascade and estimate the number of potential congenital syphilis cases averted. Sex Transm Dis 2018; 45 (9S suppl 1): S23-S28
- 11 Biswas HH, Chew Ng RA, Murray EL. et al. Characteristics associated with delivery of an infant with congenital syphilis and missed opportunities for prevention-California, 2012 to 2014. Sex Transm Dis 2018; 45 (07) 435-441
- 12 Centers for Disease Control and Prevention. STI Statistics. Accessed July 29, 2025 at: https://www.cdc.gov/sti-statistics/data-vis/table-syph-congenital-yearrace.html
- 13 Arditi B, Emont J, Friedman AM, D'Alton ME, Wen T. Deliveries among patients with maternal hepatitis C virus infection in the United States, 2000-2019. Obstet Gynecol 2023; 141 (04) 828-836
- 14 American Academy of Family Physicians; American College of Nurse-Midwives; American College of Obstetricians and Gynecologists; Association of Women's Health, Obstetric and Neonatal Nurses; National Association of Nurse Practitioners in Women's Health; and Society for Maternal-Fetal Medicine. Call to Action: Routine Hepatitis C Screening in Pregnancy. Accessed July 29, 2025 at: https://www.acog.org/-/media/project/acog/acogorg/files/pdfs/news/routine-hepatitis-c-screening-pregnancy_call-to-action.pdf
- 15 Centers for Disease Control and Prevention. Hepatitis C. Clinical Screening and Diagnosis for Hepatitis C. Accessed July 29, 2025 at: https://www.cdc.gov/hepatitis-c/hcp/diagnosis-testing/index.html
- 16 Owens DK, Davidson KW, Krist AH. et al.; US Preventive Services Task Force. Screening for Hepatitis C virus infection in adolescents and adults: US Preventive Services Task Force Recommendation Statement. JAMA 2020; 323 (10) 970-975
- 17 Khan MA, Thompson WW, Osinubi A. et al. Testing for Hepatitis C during pregnancy among persons with Medicaid and commercial insurance: Cohort study. JMIR Public Health Surveill 2023; 9: e40783
- 18 Kaufman HW, Osinubi A, Meyer III WA. et al. Hepatitis C virus testing during pregnancy after universal screening recommendations. Obstet Gynecol 2022; 140 (01) 99-101
- 19 Trivedi S, Williams C, Torrone E, Kidd S. National trends and reported risk factors among pregnant women with syphilis in the United States, 2012-2016. Obstet Gynecol 2019; 133 (01) 27-32
- 20 Thompson LA, Plitt SS, Gratrix J, Charlton CL. Prevalence of syphilis coinfection in hepatitis C virus positive prenatal patients from Alberta during a pilot routine screening program. Can Liver J 2023; 6 (01) 70-75
- 21 Centers for Disease Control and Prevention. Effects of HIV, Viral Hepatitis, STDs, & Tuberculosis Prevention. Accessed July 29, 2025 at: https://www.cdc.gov/pregnancy-hiv-std-tb-hepatitis/effects/
- 22 Aslam MV, Owusu-Edusei K, Nesheim SR, Gray KM, Lampe MA, Dietz PM. Trends in women with an HIV diagnosis at delivery hospitalization in the United States, 2006-2014. Public Health Rep 2020; 135 (04) 524-533
- 23 Kidd S, Torrone E, Su J, Weinstock H. Reported primary and secondary syphilis cases in the United States: Implications for HIV infection. Sex Transm Dis 2018; 45 (9S suppl 1): S42-S47
- 24 Harris AM, Isenhour C, Schillie S, Vellozzi C, Hepatitis B. Hepatitis B virus testing and care among pregnant women using commercial claims data, United States, 2011-2014. Infect Dis Obstet Gynecol 2018; 2018: 4107329
- 25 Kidd SE, Grey JA, Torrone EA, Weinstock HS. Increased methamphetamine, injection drug, and heroin use among women and heterosexual men with primary and secondary syphilis - United States, 2013-2017. MMWR Morb Mortal Wkly Rep 2019; 68 (06) 144-148
- 26 Centers for Disease Control and Prevention. Morbidity and Mortality Weekly Report. Substance Use Among Persons with Syphilis During Pregnancy — Arizona and Georgia, 2018–2021. Accessed July 29, 2025 at: https://www.cdc.gov/mmwr/volumes/72/wr/mm7203a3.htm
- 27 Red Book: 2024–2027 Report of the Committee on Infectious Diseases (33rd Edition). pp: 825–841
- 28 Michelow IC, Wendel Jr GD, Norgard MV. et al. Central nervous system infection in congenital syphilis. N Engl J Med 2002; 346 (23) 1792-1798
- 29 Ropper AH. Neurosyphilis. N Engl J Med 2019; 381 (14) 1358-1363 . Erratum in: N Engl J Med. 2019 Oct 31;381(18):1789. Doi: 10.1056/NEJMx190030. Erratum in: N Engl J Med. 2023 Nov 9;389(19):1828
- 30 Chau J, Atashband S, Chang E, Westerberg BD, Kozak FK. A systematic review of pediatric sensorineural hearing loss in congenital syphilis. Int J Pediatr Otorhinolaryngol 2009; 73 (06) 787-792
- 31 Kimball A, Bowen VB, Miele K. et al. Congenital syphilis diagnosed beyond the neonatal period in the United States: 2014-2018. Pediatrics 2021; 148 (03) e2020049080
- 32 Wozniak PS, Cantey JB, Zeray F. et al. The mortality of congenital syphilis. J Pediatr 2023; 263: 113650
- 33 Basu S, Kumar A. Varied presentations of early congenital syphilis. J Trop Pediatr 2013; 59 (03) 250-254
- 34 O'Connor NP, Burke PC, Worley S, Kadkhoda K, Goje O, Foster CB. Outcomes after positive syphilis screening. Pediatrics 2022; 150 (03) e2022056457
- 35 Dai Y, Zhai G, Zhang S, Chen C, Li Z, Shi W. The clinical characteristics and serological outcomes of infants with confirmed or suspected congenital syphilis in Shanghai, China: A hospital-based study. Front Pediatr 2022; 10: 802071
- 36 Keuning MW, Kamp GA, Schonenberg-Meinema D, Dorigo-Zetsma JW, van Zuiden JM, Pajkrt D. Congenital syphilis, the great imitator-case report and review. Lancet Infect Dis 2020; 20 (07) e173-e179
- 37 Umapathi KK, Thavamani A, Chotikanatis K. Incidence trends, risk factors, mortality and healthcare utilization in congenital syphilis-related hospitalizations in the United States: A nationwide population analysis. Pediatr Infect Dis J 2019; 38 (11) 1126-1130
- 38 Salomè S, Cambriglia MD, Scarano SM. et al. Congenital syphilis in the twenty-first century: an area-based study. Eur J Pediatr 2023; 182 (01) 41-51
- 39 Su JR, Brooks LC, Davis DW, Torrone EA, Weinstock HS, Kamb ML. Congenital syphilis: trends in mortality and morbidity in the United States, 1999 through 2013. Am J Obstet Gynecol 2016; 214 (03) 381.e1-381.e9