Abstract
Objective: Congenital syphilis (CS) continues to be a prevalent but preventable cause of infant morbidity and mortality. This study investigates the characteristics of women who delivered infants diagnosed with CS.
Methods: Retrospective data were collected from electronic medical records of 231 mother-newborn dyads diagnosed with CS at delivery in Community Regional Medical Center, a tertiary care hospital in Fresno, California, USA, between January 2010 and December 2018. T-tests and Fisher’s exact tests compared maternal and neonatal characteristics by syphilis treatment and prenatal care status. Log-linear models estimated relative risks (RRs) and 95% confidence intervals (CIs) for predictors of no prenatal care and no or inadequate treatment. All statistical tests were two-sided with an alpha level of 0.05.
Results: Twenty-one percent of women did not receive prenatal care, 51.5% received inadequate treatment, and 15% received no treatment for syphilis during pregnancy. No or insufficient syphilis treatment was more common among unemployed women, those who used drugs, smoked, had Medicaid, had no prenatal care, were incarcerated, or had abnormal neonatal outcomes. Drug use during pregnancy was associated with a 1.26-fold increased risk of receiving no or inadequate treatment (RR: 1.26, CI: 1.03-1.54) and a 3.32-fold increased risk (RR: 3.32, CI: 1.64-6.71) of having no prenatal care compared to women who did not use drugs.
Conclusion: Women from minority groups who were unmarried, unemployed, homeless, or using illicit drugs were more likely to receive inadequate prenatal care and no treatment for syphilis during pregnancy. Strengthening public health infrastructure to test and provide care for these high-risk pregnant women is urgently required.
Keywords: barriers to healthcare access, congenital syphilis, drug use, inadequate prenatal care, inadequate treatment of syphilis, prenatal care, treatment of syphilis
Introduction
Syphilis is a sexually transmitted infection (STI) caused by Treponema pallidum. Congenital syphilis (CS) occurs when this infection is vertically transmitted from mother to child transplacentally while pregnant and/or during delivery due to contact with maternal lesions or genital secretions. CS can result in various manifestations of varying severity, such as early fetal loss, stillbirth, premature birth, low birth weight, congenital disabilities, blindness, hearing loss, and even neonatal and infant death [1]. Penicillin G is the only known effective antimicrobial for treating syphilis in women, thereby preventing maternal transmission to the fetus. Penicillin is also the only drug that is used to treat CS. Based on the sexually transmitted disease (STD) treatment guidelines issued by the Centers for Disease Control and Prevention (CDC) in 2015, treatment of syphilis in pregnancy depends on the duration of infection. Primary, secondary, and early latent syphilis of less than one year should be treated with a single dose of 2.4 million units of benzathine penicillin G. In contrast, late, latent, or unknown duration of syphilis should be treated with benzathine penicillin G 2.4 million units once per week for three weeks. In pregnancy, there must be a strict seven-day gap between doses. One study evaluated the efficacy of treatment of syphilis with penicillin as recommended by the CDC and found that treatment with penicillin had a 98.2% success rate in preventing CS [2]. Adequate maternal treatment is defined as completion of a penicillin-based regimen recommended for the mother’s stage of syphilis initiated ≥30 days before delivery [3].
The United States Preventive Services Task Force and CDC recommend screening pregnant women for syphilis during their first prenatal visit. Screening again in the third trimester is promoted for women at increased risk of acquiring syphilis. [3,4] Even in areas where third-trimester screening is recommended, it has often been implemented at low rates. One study in Miami found that only 11% of women were re-screened in the third trimester, and another study from Texas found that only five of 31 providers routinely screened twice during pregnancy [5,6]. Despite the availability of testing and treatment, many pregnant women are not getting tested and are not receiving treatment for syphilis.
Based on the 2017 report by the CDC STD Control Branch, the United States has seen a surge in CS cases from 2011 to 2015. Trends in Western and Southern states drive national increases, with California accounting for approximately a third of the country’s total CS cases [7].
Fresno County, the setting of this study, is among the most affected counties in the United States for CS cases [8,9]. The county experiences high rates of poverty, drug use, STDs, and a shortage of healthcare workers. While previous research has primarily focused on urban settings, limited evidence is available regarding syphilis and CS in rural populations. This study aims to identify risk factors associated with inadequate prenatal care and insufficient treatment for syphilis among pregnant women in this context.
The objectives of this study are to describe the characteristics of women affected by syphilis during pregnancy and to investigate risk factors associated with inadequate prenatal care and insufficient treatment for syphilis.
Materials and methods
A retrospective chart review was conducted at Community Regional Medical Center, a tertiary care 650-bed hospital in Fresno, California, USA. Mother-infant dyads with an International Classification of Diseases, Ninth Revision (ICD-9) or Tenth Revision (ICD-10) diagnosis of syphilis and a live-born infant delivered between January 1, 2010, and December 31, 2018 [10], were included, as shown in Table 1.
Table 1. International Classification of Disease (ICD) codes used to identify syphilis diagnoses.
This table lists the International Classification of Diseases, Ninth Revision (ICD-9), and Tenth Revision (ICD-10), diagnosis codes used to identify maternal syphilis complicating pregnancy, childbirth, or the puerperium, as well as early and late congenital syphilis in neonates and children. These codes were used for case identification and classification in the study.
Source: [10]
| ICD-9 and ICD-10 Codes | Diagnosis |
| 64700 | Syphilis of mother, complicating pregnancy, unspecified episode of care |
| 64701 | Syphilis of mother, complicating pregnancy, delivered |
| 64702 | Syphilis of mother, complicating pregnancy, delivered with postpartum complication |
| 64703 | Syphilis of mother, complicating pregnancy, antepartum |
| 64704 | Syphilis of mother, complicating pregnancy, postpartum |
| 098111 | Syphilis complicating pregnancy, first trimester |
| 098112 | Syphilis complicating pregnancy, second trimester |
| 098113 | Syphilis complicating pregnancy, third trimester |
| 098119 | Syphilis complicating pregnancy, unspecified trimester |
| 09812 | Syphilis complicating childbirth |
| 09813 | Syphilis complicating the puerperium |
| A5009 | Other early congenital syphilis, symptomatic |
| A501 | Early congenital syphilis, latent |
| A502 | Early congenital syphilis, unspecified |
| A5030 | Late congenital syphilitic oculopathy, unspecified |
| A5031 | Late congenital syphilitic interstitial keratitis |
| A5032 | Late congenital syphilitic chorioretinitis |
| A5039 | Other late congenital syphilitic oculopathy |
Detailed data were collected regarding maternal and newborn characteristics. Maternal data were self-reporpted and included age, ethnicity (Caucasian, Hispanic, African American, Asian, American Indian, Mixed Ethnicity), insurance (Medical/Medicaid or Private), employment status (employed or unemployed), marital status (married, unmarried or divorced), incarceration (yes, no, unknown), presence of domestic violence (yes, no, unknown), homelessness (yes, no, unknown), smoking by mother (yes, no, unknown), alcohol use by mother (yes, no, unknown) drug use by mother (yes, no, unknown), type of drug use (methamphetamine, marijuana, opiates), other sexually transmitted infections during pregnancy (herpes simplex virus, chlamydia, gonorrhea, HIV), having prenatal care (yes, no), maternal treatment (adequate, inadequate, none, unknown), gestational age of baby at delivery (less than 32 weeks, 33-37 weeks, greater than 37 weeks), Group B Streptococcus screening status of mother (positive, negative, unknown), infant data collected included gestational age of baby at delivery (less than 32 weeks, 33 to 37 weeks, greater than 37 weeks), symptoms at delivery, and results of cerebrospinal fluid exam and treatment received.
Based on the Red Book of Pediatric Infectious Diseases, inadequate treatment for syphilis is defined as no treatment, undocumented treatment, treatment four weeks or less before delivery, treatment with a non-penicillin drug, or maternal evidence of reinfection or relapse (fourfold or greater increase in maternal rapid plasma reagin titers). Adequate treatment is defined as maternal penicillin treatment during pregnancy and more than four weeks before delivery, with no evidence or concern of maternal reinfection or relapse [11].
Statistical analysis
Frequency distributions were tabulated and examined for all variables, and data were reviewed for statistical outliers. T-tests and Fisher’s exact tests compared continuous and categorical maternal and neonatal characteristics, respectively, by syphilis treatment (adequate vs. no/inadequate) and prenatal care status (yes vs. no). Continuous predictors included maternal age, and categorical predictors included race/ethnicity, insurance status, marital status, prenatal care status, employment status, homelessness, domestic violence, incarceration status, drug use, smoking, alcohol use, STI status, gestational age, syphilis treatment status, and physical exam status in the newborn. Log-linear models estimated relative risks (RRs) and 95% confidence intervals (CIs) for significant predictors of no prenatal care and no/inadequate treatment. As the study did not aim for causal inference, only simple log-linear models were applied. All statistical analyses were performed using SAS Version 9.4 (SAS Institute Inc, Cary, NC, USA). Two-sided tests were used, and p-values < 0.05 were considered statistically significant.
Results
Substance use was reported in 136 women (58.9%), including methamphetamine (48.5%), marijuana (24.7%), opiates (6.5%), smoking (33.8%), and alcohol (14%). Concomitant STDs included herpes simplex (26.4%), chlamydophila (15.2%), gonorrhea (4.8%), and HIV (2.6%). Herpes simplex infection was confirmed by a positive maternal IgM antibody test. Of the 231 women, 21% received no prenatal care, 51.5% received inadequate treatment, and 15% received no treatment for syphilis during pregnancy (Table 2).
Table 2. Characteristics of study participants (n=231).
ᵃP-values were obtained from Fisher’s exact test for categorical variables, and t-tests for continuous variables (i.e., maternal age). Abbreviations: SD = standard deviation; CSF VDRL = cerebrospinal fluid Venereal Disease Research Laboratory test; GBS = Group B Streptococcus; HSV = herpes simplex virus; IM = intramuscular; IV = intravenous.
| Characteristic | Category | All n (%) | Adequate Treatment n (row %) | No or Inadequate Treatment n (row %) | p-valueᵃ | Any Prenatal Care n (row %) | No Prenatal Care n (row %) | p-valueᵃ |
| Age (years) | Mean (SD) | 27.3 (5.4) | 26.3 (5.6) | 27.8 (5.3) | 0.039 | 27.0 (5.4) | 27.9 (5.0) | 0.274 |
| Race/ethnicity | Caucasian | 57 (25.2) | 16 (28.1) | 41 (71.9) | 0.368 | 39 (68.4) | 16 (28.1) | 0.205 |
| Hispanic | 142 (62.8) | 49 (34.5) | 91 (64.1) | 106 (74.7) | 27 (19.0) | |||
| African American | 20 (8.9) | 7 (35.0) | 13 (65.0) | 15 (75.0) | 5 (25.0) | |||
| Asian | 5 (2.2) | 1 (20.0) | 4 (80.0) | 3 (60.0) | 2 (40.0) | |||
| American Indian | 1 (0.4) | 1 (100) | 0 (0) | 1 (100) | 0 (0) | |||
| Mixed ethnicity | 1 (0.4) | 0 (0) | 1 (100) | 1 (100) | 0 (0) | |||
| Missing | 5 (2.2) | 1 (20.0) | 3 (60.0) | 3 (60.0) | 0 (0) | |||
| Health insurance | Medical/Medicaid | 221 (95.7) | 71 (32.1) | 149 (67.4) | 0.003 | 0.0002 | ||
| Private | 4 (1.7) | 2 (50.0) | 2 (50.0) | |||||
| Missing | 6 (2.6) | 2 (33.3) | 2 (33.3) | |||||
| Marital status | Married | 15 (6.5) | 3 (20.0) | 12 (80.0) | 0.011 | 0.002 | ||
| Unmarried | 205 (88.7) | 68 (33.2) | 136 (66.3) | |||||
| Divorced | 5 (2.2) | 2 (40.0) | 3 (60.0) | |||||
| Missing | 6 (2.6) | 2 (33.3) | 2 (33.3) | |||||
| Prenatal care | None | 50 (21.7) | 6 (12) | 44 (88) | < .0001> | |||
| Any | 168 (72.7) | 60 (35.7) | 106 (63.1) | |||||
| Missing | 13 (5.6) | 9 (69.2) | 3 (23.1) | |||||
| Employment | Employed | 17 (7.4) | 8 (47.1) | 9 (52.9) | 0.003 | 9 (52.9) | 4 (23.5) | < .0001> |
| Unemployed | 207 (89.6) | 64 (30.9) | 142 (68.6) | 156 (75.4) | 46 (22.2) | |||
| Unknown | 7 (3) | 3 (42.9) | 2 (28.6) | 3 (42.9) | 0 (0) | |||
| Homeless | Yes | 18 (7.8) | 4 (22.2) | 14 (77.8) | 0.498 | 8 (44.4) | 10 (55.6) | 0.002 |
| No | 77 (33.3) | 29 (37.7) | 48 (62.3) | 60 (77.9) | 16 (20.8) | |||
| Unknown | 136 (58.9) | 42 (30.9) | 91 (66.9) | 100 (73.5) | 24 (17.7) | |||
| Domestic violence | Yes | 11 (4.8) | 3 (27.3) | 8 (72.7) | 0.913 | 8 (72.7) | 3 (27.3) | 0.139 |
| No | 50 (21.7) | 18 (36) | 32 (64) | 42 (84) | 8 (16) | |||
| Unknown | 170 (73.6) | 54 (31.8) | 113 (66.5) | 118 (69.4) | 39 (22.9) | |||
| Incarceration | Yes | 17 (7.4) | 9 (52.9) | 8 (47.1) | 0.001 | 14 (82.4) | 3 (17.7) | 0.001 |
| No | 208 (90) | 64 (30.8) | 143 (68.8) | 152 (73.1) | 47 (22.6) | |||
| Unknown | 6 (2.6) | 2 (33.3) | 2 (33.3) | 2 (33.3) | 0 (0) | |||
| Drug use | Yes | 136 (58.9) | 36 (26.5) | 98 (72.1) | 0.002 | 91 (66.9) | 42 (30.9) | < .0001> |
| No | 93 (40.3) | 39 (41.9) | 54 (58.1) | 76 (81.7) | 8 (8.6) | |||
| Unknown | 2 (0.9) | 0 (0) | 1 (50) | 1 (50) | 0 (0) | |||
| Methamphetamines | Yes | 112 (48.5) | 26 (23.2) | 84 (75) | 0.0003 | 37 (33) | 73 (65.2) | < .0001> |
| No | 117 (50.7) | 49 (41.9) | 68 (58.1) | 13 (11.1) | 94 (80.3) | |||
| Unknown | 2 (0.9) | 0 (0) | 1 (50) | 0 (0) | 1 (50) | |||
| Marijuana | Yes | 57 (24.7) | 17 (29.8) | 39 (68.4) | 0.043 | 0.011 | ||
| No | 172 (74.5) | 58 (33.7) | 113 (65.7) | |||||
| Unknown | 2 (0.9) | 0 (0) | 1 (50) | |||||
| Opiate | Yes | 15 (6.5) | 3 (20) | 12 (80) | 0.047 | 5 (33.3) | 9 (60) | 0.147 |
| No | 214 (92.6) | 72 (33.6) | 140 (65.4) | 45 (21) | 158 (73.8) | |||
| Unknown | 2 (0.9) | 0 (0) | 1 (50) | 0 (0) | 1 (50) | |||
| Smoking | Yes | 78 (33.8) | 21 (26.9) | 57 (73.1) | 0.019 | 0.062 | ||
| No | 151 (65.4) | 54 (35.8) | 95 (62.9) | |||||
| Unknown | 2 (0.9) | 0 (0) | 1 (50) | |||||
| Alcohol | Yes | 14 (6.1) | 6 (42.9) | 8 (57.1) | 0.052 | 9 (64.3) | 5 (35.7) | 0.165 |
| No | 215 (93.1) | 69 (32.1) | 144 (67) | 158 (73.5) | 45 (20.9) | |||
| Unknown | 2 (0.9) | 0 (0) | 1 (50) | 1 (50) | 0 (0) | |||
| HSV | Yes | 61 (26.4) | 18 (29.5) | 43 (70.5) | 0.385 | 52 (85.3) | 7 (11.5) | 0.046 |
| No | 28 (12.1) | 13 (46.4) | 15 (53.6) | 22 (78.6) | 6 (21.4) | |||
| Unknown | 142 (61.5) | 44 (31) | 95 (66.9) | 94 (66.2) | 37 (26.1) | |||
| Chlamydia | Yes | 35 (15.2) | 7 (20) | 28 (80) | 0.048 | 21 (60) | 14 (40) | < .0001> |
| No | 155 (67.1) | 58 (37.4) | 96 (61.9) | 126 (81.3) | 23 (14.8) | |||
| Unknown | 41 (17.8) | 10 (24.4) | 29 (70.7) | 21 (51.2) | 13 (31.7) | |||
| Gonorrhea | Yes | 11 (4.8) | 1 (9.1) | 10 (90.9) | 0.053 | 6 (54.6) | 5 (45.5) | 0.0003 |
| No | 178 (77.1) | 64 (36) | 113 (63.5) | 141 (79.2) | 31 (17.4) | |||
| Unknown | 42 (18.2) | 10 (23.8) | 30 (71.4) | 21 (50) | 14 (33.3) | |||
| HIV | Yes | 6 (2.6) | 1 (16.7) | 5 (83.3) | 0.025 | 5 (83.3) | 1 (16.7) | 0.016 |
| No | 213 (92.2) | 71 (33.3) | 141 (66.2) | 156 (73.2) | 48 (22.5) | |||
| Unknown | 12 (5.2) | 3 (25) | 7 (58.3) | 7 (58.3) | 1 (8.3) | |||
| GBS status | Positive | 82 (35.5) | 31 (37.8) | 50 (61) | 0.164 | 0.001 | ||
| Negative | 115 (49.8) | 38 (33) | 76 (66.1) | |||||
| Unknown | 34 (14.7) | 6 (17.7) | 27 (79.4) | |||||
| Mother treatment | Adequate | 75 (32.5) | 60 (80.0) | 6 (8.0) | < .0001> | |||
| Inadequate | 119 (51.5) | 93 (78.2) | 25 (21.0) | |||||
| None | 34 (14.7) | 13 (38.2) | 19 (55.9) | |||||
| Unknown | 1 (0.4) | 2 (66.7) | 0 (0) | |||||
| Gestational age | <32 Weeks | 19 (8.2) | 2 (10.5) | 16 (84.2) | 0.005 | 13 (68.4) | 6 (31.6) | 0.049 |
| 33-37 Weeks | 57 (24.7) | 12 (21.1) | 45 (79) | 36 (63.2) | 19 (33.3) | |||
| > 37 Weeks | 155 (67.1) | 61 (39.4) | 92 (59.4) | 119 (76.8) | 25 (16.1) | |||
| CSF VDRL | Yes | 113 (48.9) | 21 (18.6) | 91 (80.5) | < .0001> | 79 (69.9) | 32 (28.3) | 0.01 |
| No | 15 (6.5) | 2 (13.3) | 13 (86.7) | 12 (80) | 3 (20) | |||
| Unknown | 103 (44.6) | 52 (50.5) | 49 (47.6) | 77 (74.8) | 15 (14.6) | |||
| Physical exam in newborn | Normal | 207 (89.6) | 70 (33.8) | 136 (65.7) | 0.002 | 154 (74.4) | 45 (21.7) | 0.001 |
| Not normal | 20 (8.7) | 4 (20) | 16 (80) | 13 (65) | 5 (25) | |||
| Unknown | 4 (1.7) | 1 (25) | 1 (25) | 1 (25) | 0 (0) | |||
| Treatment in newborn | Yes | 220 (95.2) | 69 (31.4) | 150 (68.2) | 0.0002 | 163 (74.1) | 50 (22.7) | < .0001> |
| No | 7 (3) | 5 (71.4) | 2 (28.6) | 4 (57.1) | 0 (0) | |||
| Unknown | 4 (1.7) | 1 (25) | 1 (25) | 1 (25) | 0 (0) | |||
| Types of treatment in newborn | IM Penicillin | 56 (24.2) | 36 (64.3) | 19 (33.9) | < .0001> | 48 (85.7) | 4 (7.1) | < .0001> |
| IV Penicillin | 139 (60.2) | 25 (18) | 114 (82) | 95 (68.4) | 42 (30.2) | |||
| both IM and IV | 28 (12.1) | 9 (32.1) | 18 (64.3) | 22 (78.6) | 4 (14.3) | |||
| Unknown | 8 (3.5) | 5 (62.5) | 2 (25) | 3 (37.5) | 0 (0) |
P-values were obtained from Fisher’s exact test for categorical variables, and t-tests for continuous variables (i.e., maternal age).
The proportion of women with no or inadequate syphilis treatment was 71.9% among Caucasian patients, 65.0% among African American patients, and 64.1% among Hispanic patients. Data for other groups were unstable due to small sample sizes. No or inadequate treatment was more common among women with Medical/Medicaid, those who were unmarried, lacked prenatal care, were unemployed, used illicit drugs, smoked, had concomitant Chlamydophila or HIV, or had a preterm delivery (Table 2).
Table 3 shows significant associations between maternal and neonatal outcomes and maternal prenatal and treatment status. Premature infants (<37 weeks) were more likely to be born to mothers with inadequate treatment. Women who used drugs, particularly methamphetamines and marijuana, were 1.26 times more likely to receive inadequate syphilis treatment (RR: 1.26, 95% CI: 1.03-1.54). Each additional year of maternal age was linked to a 1.0% increase in risk for insufficient treatment. Having an STI, such as chlamydophila or gonorrhea, was also associated with a higher likelihood of no or inadequate treatment.
Table 3. Maternal and neonatal characteristics significantly associated with having inadequate treatment and no prenatal care.
aData are expressed as RR (95% CI). Relative risks were estimated using log-binomial regression models. Two-sided tests were used, and p-values < 0.05 were considered statistically significant.
Abbreviations: RR = relative risk; CI = confidence interval; IM = intramuscular; IV = intravenous; NS = not significant.
| Characteristic | Category | Inadequate Treatment RR (95% CI)a | No Prenatal Care RR (95% CI) a |
| Maternal age (years) | Per year increase | 1.01 (1.00–1.03) | NS |
| Homelessness | Yes | NS | 2.64 (1.45–4.81) |
| No | Reference | Reference | |
| Drug use | Yes | 1.26 (1.03–1.54) | 3.32 (1.64–6.71) |
| No | Reference | Reference | |
| Methamphetamine use | Yes | 1.31 (1.09–1.58) | 2.77 (1.56–4.91) |
| No | Reference | Reference | |
| Marijuana use | Yes | NS | 1.96 (1.22–3.16) |
| No | Reference | Reference | |
| Chlamydia | Yes | 1.28 (1.04–1.58) | 2.59 (1.49–4.51) |
| No | Reference | Reference | |
| Gonorrhea | Yes | 1.42 (1.15–1.77) | 2.52 (1.23–5.19) |
| No | Reference | Reference | |
| Gestational age | <32 weeks | 1.48 (1.20–1.82) | 1.82 (0.86–3.86) |
| 33–37 weeks | 1.31 (1.09–1.58) | 1.99 (1.20–3.31) | |
| >37 weeks | Reference | Reference | |
| Type of maternal treatment | IM penicillin | Reference | Reference |
| IV penicillin | 2.37 (1.64–3.44) | 3.99 (1.50–10.56) | |
| Both IM and IV | 1.93 (1.23–3.03) | 2.00 (0.54–7.36) |
Women who used marijuana were 1.96 times more likely to have received no prenatal care. Those with concomitant chlamydia during pregnancy were 2.59 times more likely to lack prenatal care. Maternal age was not significantly associated with prenatal care. Women who used drugs had a 3.32-fold increased risk (RR: 3.32, 95% CI: 1.64-6.71) of having no prenatal care, especially those using methamphetamines and marijuana. Concomitant STDs, such as gonorrhea and chlamydophila, were also linked to inadequate prenatal care. Homeless women had 2.64 times the risk of no or insufficient prenatal care compared to those with housing (RR: 2.64, 95% CI: 1.45-4.81).
Discussion
This study addresses a significant gap in the understanding of CS and corroborates the national trend of increasing CS cases since 2012. The retrospective chart review identified 231 mother-infant dyads diagnosed with syphilis during pregnancy and/or CS over nine years (Table 4). As shown in Table 4, the number of CS cases in Fresno County, California, has steadily increased since 2012. The findings demonstrate a strong association between inadequate prenatal care and insufficient treatment for syphilis.
Table 4. Number of congenital syphilis cases per year.
Source: [9]
| Year of Birth | Frequency | Percentage of Live Births |
| 2010 | 2 | 0.87 |
| 2011 | 3 | 1.30 |
| 2012 | 2 | 0.87 |
| 2013 | 16 | 6.93 |
| 2014 | 24 | 10.39 |
| 2015 | 41 | 17.75 |
| 2016 | 60 | 25.97 |
| 2017 | 45 | 19.48 |
| 2018 | 38 | 16.45 |
Although previous literature has examined risk factors for women delivering infants with CS, most studies have focused on urban populations. Mobley et al. investigated CS in a rural population in South Carolina and found that pregnant women with syphilis were more likely to deliver infants with CS than their urban counterparts [12]. Additional studies have identified racial and ethnic disparities in access to adequate prenatal care [13,14]. Slutsker et al. reported that 77.9% of women who delivered an infant with CS were Black or Hispanic women [15]. The present study demonstrates that other demographic and maternal characteristics are also statistically significant.
Studies show that CS is linked to lack of prenatal care, inadequate or no treatment, and a high rate of sexually transmitted diseases. Kidd et al. estimated that 75% of potential CS cases were successfully averted with proper prenatal care, testing, and adequate treatment [16]. A California study of missed opportunities to prevent CS identified gaps at multiple steps in the prevention cascade and found that early prenatal care is critical to preventing CS and that multifaceted efforts are needed [17].
The findings of this study are consistent with previous research and highlight the importance of adequate prenatal care and treatment in reducing CS cases. Li et al. demonstrated that programs implemented to prevent mother-to-child transmission of syphilis in Shanghai from 2001 to 2015 averted 39.4% of early fetal losses or stillbirths, 16.4% of neonatal deaths, 8.8% of prematurity or low birth weight, and 35.4% of CS cases [18]. Early prenatal care and STD testing are essential to protect women and infants from the severe consequences of this disease.
Future research should examine barriers to healthcare access, prenatal care, and immigration status. Further investigation is warranted to develop innovative strategies for patient motivation and education, implement community awareness campaigns, and provide prenatal care in sexually transmitted disease clinics. STD control programs should intensify efforts to identify women with STDs and drug use, ensuring these patients receive appropriate education.
Strategies that prioritize local community-level interventions to identify women at higher risk for maternal syphilis are essential. Identification, testing, treatment, and education constitute the foundation of this approach.
Case finding may be conducted at local drug rehabilitation centers, primary care offices, emergency departments, and hospitals. Care coordinators should be trained to track positive cases and facilitate referrals for appropriate treatment. States and localities with higher rates of CS should prioritize this issue due to the significant adverse outcomes for infants and children.
In states and counties with a higher incidence of CS, pregnancy testing should be routinely conducted alongside syphilis testing to facilitate early identification of syphilis cases. With sufficient funding, this testing could be expanded to all major sites in high-risk neighborhoods, potentially reducing CS incidence.
Mass awareness campaigns, conducted in collaboration with community partners serving vulnerable populations, can increase awareness of CS and emphasize prevention. Health policymakers, healthcare organizations, hospitals, and public health departments should collaborate to ensure that affected populations have access to care. A comprehensive and coordinated approach is required to reduce CS rates and improve maternal and child health outcomes. Sufficient financial resources are essential for the effective implementation of community outreach programs.
The primary strengths of this study include a large sample size for a rare condition, an extended study period, and comprehensive clinical and sociodemographic data collection from a high-burden rural setting. These factors enabled the inclusion of a robust cohort of CS cases. Nevertheless, the single-center, retrospective design restricts the generalizability of the findings to other populations. Furthermore, reliance on self-reported data, potential misclassification, and loss to follow-up among many women and their children limit the ability to draw definitive conclusions regarding long-term outcomes. A considerable proportion of women in this cohort did not receive prenatal care, which may confound the observed associations between maternal characteristics and treatment adequacy. Consequently, these results should be interpreted descriptively rather than as evidence of causality.
Conclusions
The study identified significant deficiencies in prenatal care and syphilis treatment among high-risk women residing in rural, underserved regions. The findings indicate that insufficient prenatal care and inadequate syphilis treatment during pregnancy are contributing factors to CS. Women from ethnic minority backgrounds who were unmarried, unemployed, homeless, or engaged in illicit drug use were disproportionately likely to receive inadequate prenatal care and no syphilis treatment, resulting in a higher likelihood of delivering infants with CS.
The study also identified key maternal factors linked to missed opportunities for prevention. Specifically, it characterized women who received no or inadequate prenatal care, which led to a lack of syphilis treatment during pregnancy. This subgroup delivered infants with CS in rural and underserved populations where the prevalence of syphilis and CS is rising annually. These results underscore the urgent need for targeted public health interventions to reduce CS rates and improve maternal and infant health outcomes.
Acknowledgments
Madeline Moua and Dr. Heather Chow helped with data collection.
Disclosures
Human subjects: Informed consent for treatment and open access publication was obtained or waived by all participants in this study.
Animal subjects: All authors have confirmed that this study did not involve animal subjects or tissue.
Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following:
Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work.
Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work.
Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work.
Author Contributions
Concept and design: Jyothi R. Patri, Richa Kaushal, Christine Nelson
Drafting of the manuscript: Jyothi R. Patri, Richa Kaushal
Critical review of the manuscript for important intellectual content: Jyothi R. Patri, Richa Kaushal, Christine Nelson, Sandie Ha, Ratnali Jain
Supervision: Jyothi R. Patri, Richa Kaushal, Christine Nelson
Acquisition, analysis, or interpretation of data: Richa Kaushal, Sandie Ha, Ratnali Jain
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