ABSTRACT:

Introduction:

Syphilis is a sexually transmitted disease, easy to diagnose and treat, but whose incidence is increasing in Brazil. This study estimated the prevalence of the non-performance of serological tests for syphilis during prenatal care, in addition to evaluating its trend and identifying its associated factors in the municipality of Rio Grande, Rio Grande do Sul, Southern Brazil.

Methods:

This is a cross-sectional survey that included all pregnant women living in this municipality who gave birth between January 1 and December 31, 2007, 2010, and 2013. A single standardized questionnaire was administered to the mothers within 48 hours of delivery, while they were still in the maternity ward. We used the χ² test for proportions and linear trend, and Poisson regression with robust adjustment in the multivariate analysis. The effect measure adopted was prevalence ratio (PR).

Results:

Among the 7,351 mothers who had at least one prenatal visit, the prevalence of non-performance of serological tests for syphilis in the three years studied was 2.9% (95% confidence interval - 95%CI 2.56 - 3.33), with 3.3% (95%CI 2.56 - 3.97) in 2007, 2.8% (95%CI 2.20 - 3.52) in 2010, and 2.7% (95%CI 2.12 - 3.38) in 2013. Black mothers, those with low household income and schooling, and who had few prenatal visits showed higher PR of non-performance of this test.

Discussion:

The prevalence of non-performance has virtually not changed in the period, and women with high-risk pregnancy showed a greater probability of not undergoing the test.

Conclusions:

This municipality needs to reach mothers with lower socioeconomic status, restructure the local health services, and enhance their operationalization to improve the quality of prenatal care.

Keywords:
Prenatal care; Pregnant women; Serology; Syphilis

INTRODUCTION

Gestational syphilis is an infectious disease of vertical transmission - from mother to fetus -, which affects at least three-fourths of newborns if not treated¹1. Qin J, Yang T, Xiao S, Tan H, Feng T, Fu H. Reported estimates of adverse pregnancy outcomes among women with and without syphilis: a systematic review and meta-analysis. PLoS One 2014; 9(7): e102203. http://doi.org/10.1371/journal.pone.0102203
https://doi.org/http://doi.org/10.1371/j... . This condition can lead to congenital syphilis, fetal loss, miscarriage, stillbirth, low birth weight, prematurity, and early neonatal mortality¹1. Qin J, Yang T, Xiao S, Tan H, Feng T, Fu H. Reported estimates of adverse pregnancy outcomes among women with and without syphilis: a systematic review and meta-analysis. PLoS One 2014; 9(7): e102203. http://doi.org/10.1371/journal.pone.0102203
https://doi.org/http://doi.org/10.1371/j... ^,22. Blencowe H, Cousens S, Kamb M, Berman S, Lawn JE. Lives Saved Tool supplement detection and treatment of syphilis in pregnancy to reduce syphilis related stillbirths and neonatal mortality. BMC Public Health 2011; 11(Supl. 3): S9. http://doi.org/10.1186/1471-2458-11-S3-S9
https://doi.org/http://doi.org/10.1186/1... .

Despite its significant harmful potential, both diagnosis and treatment, management, or control are easy to implement³3. Brasil. Ministério da Saúde. Atenção ao pré-natal de baixo risco [Internet]. Brasília: Ministério da Saúde; 2012 [acessado em 27 out. 2017]. 318 p. (Série A. Normas e Manuais Técnicos) (Cadernos de Atenção Básica, n. 32). Disponível em: Disponível em: http://bvsms.saude.gov.br/bvs/publicacoes/cadernos_atencao_basica_32_prenatal.pdf
http://bvsms.saude.gov.br/bvs/publicacoe... . Detection involves serological screening of pregnant women with non-treponemal tests, usually the venereal disease research laboratory (VDRL) and the rapid test (rapid plasma reagin)³3. Brasil. Ministério da Saúde. Atenção ao pré-natal de baixo risco [Internet]. Brasília: Ministério da Saúde; 2012 [acessado em 27 out. 2017]. 318 p. (Série A. Normas e Manuais Técnicos) (Cadernos de Atenção Básica, n. 32). Disponível em: Disponível em: http://bvsms.saude.gov.br/bvs/publicacoes/cadernos_atencao_basica_32_prenatal.pdf
http://bvsms.saude.gov.br/bvs/publicacoe... ^,44. Brasil. Ministério da Saúde. Orientações para implantação dos testes rápidos de HIV e sífilis na Atenção Básica. Brasília: Ministério da Saúde ; 2012. 18 p.. The treatment, benzathine penicillin-based, is highly effective and low-cost. The control must be done at the beginning of prenatal care and near the 30^th week of pregnancy³3. Brasil. Ministério da Saúde. Atenção ao pré-natal de baixo risco [Internet]. Brasília: Ministério da Saúde; 2012 [acessado em 27 out. 2017]. 318 p. (Série A. Normas e Manuais Técnicos) (Cadernos de Atenção Básica, n. 32). Disponível em: Disponível em: http://bvsms.saude.gov.br/bvs/publicacoes/cadernos_atencao_basica_32_prenatal.pdf
http://bvsms.saude.gov.br/bvs/publicacoe... ^,55. Viellas EF, Domingues RMSM, Dias MAB, Gama SGN, Theme Filha MM, Costa JV, et al. Assistência pré-natal no Brasil. Cad Saúde Pública 2014: 30(Supl. 1): S85-S100. http://dx.doi.org/10.1590/0102-311X00126013
https://doi.org/http://dx.doi.org/10.159... .

Despite almost all Brazilian pregnant women (98%) starting prenatal care, estimates indicate that at least 10% of them do not undergo a single serological test for syphilis³3. Brasil. Ministério da Saúde. Atenção ao pré-natal de baixo risco [Internet]. Brasília: Ministério da Saúde; 2012 [acessado em 27 out. 2017]. 318 p. (Série A. Normas e Manuais Técnicos) (Cadernos de Atenção Básica, n. 32). Disponível em: Disponível em: http://bvsms.saude.gov.br/bvs/publicacoes/cadernos_atencao_basica_32_prenatal.pdf
http://bvsms.saude.gov.br/bvs/publicacoe... ^,55. Viellas EF, Domingues RMSM, Dias MAB, Gama SGN, Theme Filha MM, Costa JV, et al. Assistência pré-natal no Brasil. Cad Saúde Pública 2014: 30(Supl. 1): S85-S100. http://dx.doi.org/10.1590/0102-311X00126013
https://doi.org/http://dx.doi.org/10.159... . Between 2003 and 2015, the rate of congenital syphilis in the country increased from 1.7 to 6.5 cases per one thousand live births, that is, from 5,172 to 19,228 cases. This increase represents a frequency 3.8 times higher⁶6. Brasil. Ministério da Saúde. Sífilis 2016 - Boletim Epidemiológico. Brasília: Secretaria de Vigilância em Saúde; 2016.. Another aspect to consider is the high incidence and underreporting of this disease among indigenous peoples⁷7. Tiago ZS, Picoli RP, Graeff SVB, Cunha RV, Arantes R. Subnotificação de sífilis em gestantes, congênita e adquirida entre povos indígenas em Mato Grosso do Sul, 2011-2014. Epidemiol Serv Saúde 2017; 26(3): 503-12. http://dx.doi.org/10.5123/s1679-49742017000300008
https://doi.org/http://dx.doi.org/10.512... . In Rio Grande do Sul, the rate jumped from 1.2 to 11.5/1,000 live births in the same period, or from 186 to 1,642 cases, a frequency nearly nine times higher. The national rate of 6.5/1,000 live births is 13 times greater than that recommended by the Pan American Health Organization for Latin America and the Caribbean - 0.5/1,000 live births⁸8. World Health Organization. Methods for surveillance and monitoring of congenital syphilis elimination within existing systems. Genebra: WHO; 2011..

The resurgence of congenital syphilis is worrying due to the high number of cases, its rapid growth, and for being the primary cause of 5.4% of all stillbirths⁶6. Brasil. Ministério da Saúde. Sífilis 2016 - Boletim Epidemiológico. Brasília: Secretaria de Vigilância em Saúde; 2016.^,99. Victora CG, Aquino EM, do Carmo Leal M, Monteiro CA, Barros FC, Szwarcwald CL. Maternal and child health in Brazil: progress and challenges. Lancet 2011; 377(9780): 1863-76. https://doi.org/10.1016/S0140-6736(11)60138-4
https://doi.org/https://doi.org/10.1016/... . Thus, identifying pregnant women with a higher probability of not undergoing the serological test for this disease, as well as creating mechanisms that allow health professionals and services to reach these women, can increase the coverage of this test and, consequently, reduce the incidence of congenital syphilis.

This study aimed to estimate the prevalence of non-performance of serological tests for syphilis, in addition to evaluating its trend and identifying its associated factors among all puerperal women living in the municipality of Rio Grande, Rio Grande do Sul, who gave birth in one of the two local maternity hospitals, in 2007, 2010, and 2013.

METHODS

Rio Grande has around 210 thousand inhabitants and is located in the so-called Southern Half of the state of Rio Grande do Sul, at 300 km from the capital Porto Alegre. Its economy is based on farming, fishing, trade, port activity, and, more recently, the construction of ship platforms. The gross domestic product (GDP) per capita in 2012 was R$ 45 thousand per year, while the child mortality coefficient was 13.5/1,000 live births¹⁰10. Fundação de Economia e Estatística Siegfried Emanuel Heuser. Município: Rio Grande [Internet]. [acessado em 16 out. 2017]. Disponível em: Disponível em: http://www.fee.tche.br/sitefee/pt/content/resumo/pg_municipios_detalhe.php?municipio=Rio+Grande
http://www.fee.tche.br/sitefee/pt/conten... .

The data presented in this study originated from cross-sectional surveys conducted periodically in the municipality to evaluate the pregnancy and childbirth care provided. The first one was carried out in 2007, the second in 2010, and the last in 2013. They covered all births that occurred in the municipality between January 1 and December 31 of these years and included only newborns with at least 20 weeks of gestational age, weighing 500 grams or more, and whose mother lived in Rio Grande, both in urban and rural areas. This article included only mothers who had at least one prenatal visit. These women were interviewed only once in the maternity ward within 48 hours of delivery.

A single standardized and pre-coded questionnaire was used, consisting almost entirely of closed questions. The information collected included demographic and socioeconomic characteristics, housing and sanitation conditions, reproductive history, lifestyle habits, morbidity pattern in the gestational period, and care received during pregnancy and childbirth. The outcome was the non-performance of serological tests for syphilis (VDRL) during prenatal visits.

Four trained interviewers - who conducted the pilot study in the month prior to data collection in these same maternity hospitals - administered the questionnaires.

The search for parturients occurred daily by consulting the birth records and visiting the two maternity wards. After finding a puerperal woman, the interviewers confirmed her place of residence, and, if it corresponded to the municipality of Rio Grande, the informed consent form (ICF) was read. If the mother agreed, she signed two copies of the form, keeping one of them, and returning the other to the interviewer for later archiving. Only after this procedure, the interviewer administered the questionnaire. In the case of underage mothers, a parent or guardian signed the ICF.

At the end of each working day, the interviewers coded the questionnaires and handed them us at the headquarters of the project so we could code the open questions. At this point, the questionnaires were also thoroughly reviewed for subsequent typing. Different professionals recorded the data with double entry and in reverse order to the first typist. At the end of each batch of 100 questionnaires, the entries were compared and any possible errors, corrected. Next, a consistency analysis was performed. Both the typing and the comparison of the data recorded were carried out using the free software EpiData 3.1¹¹11. Lauritsen JM, editor. EpiData Data Entry, Data Management and basic Statistical Analysis System [Internet]. Odense: EpiData Association; 2000-2008 [acessado em 20 out. 2017]. Disponível em: Disponível em: http://www.epidata.dk
http://www.epidata.dk... . At the end of this stage, the data was stored, and derived variables created. These stages were performed using the statistical software Stata 12¹²12. Stata Corp. Stata statistical software: release 11.2. College Station: Stata Corporation; 2011..

The descriptive analysis consisted of obtaining prevalence measures of both exposures and the outcome. The effect measure used was prevalence ratio (PR), calculated by Poisson regression with robust variance adjustment¹³13. Barros AJ, Hirakata VN. Alternatives for logistic regression in cross-sectional studies: an empirical comparison of models that directly estimate the prevalence ratio. BMC Med Res Methodol 2003; 3: 21. https://doi.org/10.1186/1471-2288-3-21
https://doi.org/https://doi.org/10.1186/... . We reported the p-value of the linear trend test for ordinal categorical variables, while other variables used the Wald test for heterogeneity.

In the adjusted analysis of factors associated with the non-performance of serological tests for syphilis, we adopted a previously established hierarchical model with three levels to adjust for potential confounding factors¹⁴14. Victora CG, Huttly SH, Fuchs SC, Olinto MT. The role of conceptual frameworks in Epidemiological analysis: a hierarchical approach. Int J Epidem 1997; 26(1): 224-7. https://doi.org/10.1093/ije/26.1.224
https://doi.org/https://doi.org/10.1093/... . The first level involved demographic (age, skin color, living with a partner) and socioeconomic variables (schooling, household income, and paid work during pregnancy); the second level included environmental (household crowding) and reproductive characteristics (parity, previous stillbirth, and whether the pregnancy was planned); and the third level comprised pregnancy care variables (number of prenatal visits, trimester of the first prenatal visit, place where the pregnant woman had the prenatal visits, type of health service used, and if the mother received ferrous sulfate supplementation). In the regression model, variables were controlled for those of the same or previous levels, establishing a p≤0.20 to maintain the variables in the analysis model proposed. The significance level adopted for two-tailed tests was 95%¹⁵15. Kirkwood BR, Sterne JAC. Essentials of medical statistics. 2ª ed. Londres: Blackwell Scientific Publications; 2003..

Quality control consisted of re-administering at least 7% of the questionnaires through telephone or home visits systematically chosen. The Kappa coefficient of agreement ranged from 0.63 to 0.89. This stage aimed to check the performance of the interviews and compare the answers received on both occasions.

The Health Research Ethics Committee (HREC) of the Universidade Federal do Rio Grande approved each research protocol, under the following process numbers: 23116.5369/6.58-12/2007; 23116.6258/9.64-117/2009; and 23116.2623/2012.67-007-2012.

RESULTS

In 2007, 2010, and 2013, the number of births from mothers who lived in the municipality of Rio Grande was 7,818. Out of this total, we could gather information about 7,637 births, which represents a respondents rate of 97.7% (or loss of 2.3%). The losses corresponded to 1.2% in 2007, 2.7% in 2010, and 2.8% in 2013. The sample of the present study consisted of 7,351 births from mothers who had at least one prenatal visit.

Table 1 shows that 18.6% of them were adolescents, 69.1% were white, 84.9% lived with a partner, 57.3% had at least completed high school, 21.3% had a monthly household income greater than four minimum wages (MW), 41.9% had paid work outside the home during pregnancy, and lived, on average, with 3.5 people. About 45% of them were primiparas, 3% had at least one previous stillbirth, and 80.6% had at least six prenatal visits. Most of the visits (56.7%) occurred in the public service, 66.9% received ferrous sulfate supplementation, and 2.9% (95% confidence interval - 95%CI 2.6 - 3.3) did not undergo a serological test for syphilis.

Table 2 reveals that the prevalence of non-performance of serological tests for syphilis ranged from 15.7 to 0.6% among pregnant women who had 1-3 prenatal visits and 12 or more, respectively. In the adjusted analysis, the variables significantly associated with the non-performance of serological tests for syphilis were skin color, maternal schooling, household income, number of prenatal visits, and ferrous sulfate supplementation.

The same table indicates that the PR of non-performance of serological tests for syphilis during prenatal care was 1.57 (1.10-2.25) among black mothers compared to white ones, and 2.40 (1.34-4.29) in mothers who belonged to families with a monthly income lower than one MW in contrast with those with household income ≥ 4 MW. The PR for mothers with up to eight years of schooling was 2.57 (95%CI 1.21 - 5.44) when compared to those with 12 or more years of schooling. Lastly, the PR of non-performance of serological tests for syphilis among mothers who had 1-3 prenatal visits was 13.23 (95%CI 11.98 - 62.22) compared to those with 12 or more visits, and 1.82 (95%CI 1.39 - 2.37) in mothers not supplemented with ferrous sulfate during pregnancy in contrast with those who received supplementation.

DISCUSSION

The prevalence of non-performance of serological tests for syphilis in this study was 2.9%, with a slight decline from 3.2% in 2007 to 2.7% in 2013. The PRs of non-performance of this test were significantly higher among black mothers, those with up to eight years of schooling, monthly household income lower than one MW, who had one to three prenatal visits, and the ones not supplemented with ferrous sulfate.

A recent hospital-based study that included all Brazilian states found a national prevalence of non-performance of 11%, ranging from 5% in the South Region to 21% in the North Region¹⁶16. Domingues RMSM, Szwarcwald CL, Souza Junior PR, Leal M do C. Prevalence of syphilis in pregnancy and prenatal syphilis testing in Brazil: birth in Brazil study. Rev Saúde Pública 2014; 48(5): 766-74. http://dx.doi.org/10.1590/S0034-8910.2014048005114
https://doi.org/http://dx.doi.org/10.159... . This difference might be attributed primarily to the greater availability and ease of access to public health services in each of these regions. In this study, black mothers presented PR of 1.57 (1.10 - 2.25) for non-performance of serological tests for syphilis when compared to white ones. In general, black women had fewer prenatal visits and started them later. These women also lived farther from health services and faced other socioeconomic barriers, such as lack of resources to pay for transport and loss of working hours, in addition to educational and cultural factors that hindered the search for prenatal care of better quality, which includes serological tests for syphilis¹⁷17. Victora CG, Matijasevich A, Silveira MF, Santos IS, Barros AJD, Barros FC. Socioeconomic and ethnic group inequities in antenatal care quality in the public and private sector in Brazil. Health Policy Plan 2010; 25(4): 253-61. https://doi.org/10.1093/heapol/czp065
https://doi.org/https://doi.org/10.1093/... .

Household income and maternal schooling are the main determinants of adequate prenatal care¹⁸18. Cesar JA, Matijasevich A, Santos IS, Barros AJ, Dias-da-Costa JS, Barros FC, et al. The use of maternal and child health services in three population-based cohorts in Southern Brazil, 1982-2004. Cad Saúde Pública 2008; 24(Supl. 3): S427-36. https://doi.org/10.1590/s0102-311x2008001500008
https://doi.org/https://doi.org/10.1590/... ^,1919. Coimbra LC, Silva AA, Mochel EG, Alves MTSS, Ribeiro VS, Aragão VMF, et al. Factors associated with inadequacy of prenatal care utilization. Rev Saúde Pública 2003; 37(4): 456-62. http://dx.doi.org/10.1590/S0034-89102003000400010
https://doi.org/http://dx.doi.org/10.159... ^,2020. Saavedra JS, Cesar JA. Uso de diferentes critérios para avaliação da inadequação do pré-natal: um estudo de base populacional no extremo Sul do Brasil. Cad Saúde Pública 2015: 31(5): 1003-14. http://dx.doi.org/10.1590/0201-311X00085014
https://doi.org/http://dx.doi.org/10.159... ^,2121. Silveira MF, Barros AJD, Santos IS, Matijasevich A, Victora CG. Socioeconomic differentials in performing urinalysis during prenatal care. Rev Saúde Pública 2008; 42(3): 389-95. http://dx.doi.org/10.1590/S0034-89102008000300001
https://doi.org/http://dx.doi.org/10.159... . A study conducted in Pelotas, Rio Grande do Sul, showed that the coverage for almost all prenatal procedures and tests was higher among pregnant women belonging to the highest quintile of income compared to the lowest¹⁸18. Cesar JA, Matijasevich A, Santos IS, Barros AJ, Dias-da-Costa JS, Barros FC, et al. The use of maternal and child health services in three population-based cohorts in Southern Brazil, 1982-2004. Cad Saúde Pública 2008; 24(Supl. 3): S427-36. https://doi.org/10.1590/s0102-311x2008001500008
https://doi.org/https://doi.org/10.1590/... .

We have found no studies reporting the probability of (non-) performance of serological tests for syphilis according to the number of prenatal visits. Only one work evaluated a similar association: urinalysis during prenatal care. In this study, Silveira et al. showed that, even after adjustment for several confounding factors, the odds ratio of non-performance of urinalysis during the prenatal period was 24.5 (10.5 - 57.4) among pregnant women who had only one prenatal visit in comparison with those who had seven or more visits²¹21. Silveira MF, Barros AJD, Santos IS, Matijasevich A, Victora CG. Socioeconomic differentials in performing urinalysis during prenatal care. Rev Saúde Pública 2008; 42(3): 389-95. http://dx.doi.org/10.1590/S0034-89102008000300001
https://doi.org/http://dx.doi.org/10.159... . That is, the provision of health care depends on the pregnant woman going to prenatal visits. The higher the number of visits to health services, the greater the probability of receiving care.

The non-supplementation with ferrous sulfate, used here as a proxy of the outcome, reinforces the idea that the non-performance of serological tests for syphilis is not selective. Namely, pregnant women who do not undergo a particular test have a high probability of not undergoing other procedures¹⁸18. Cesar JA, Matijasevich A, Santos IS, Barros AJ, Dias-da-Costa JS, Barros FC, et al. The use of maternal and child health services in three population-based cohorts in Southern Brazil, 1982-2004. Cad Saúde Pública 2008; 24(Supl. 3): S427-36. https://doi.org/10.1590/s0102-311x2008001500008
https://doi.org/https://doi.org/10.1590/... ^,2222. Cesar JA, Dumith SC, Chrestani MAD, Mendoza-Sassi RA. Iron supplementation among pregnant women: results from a population-based survey study. Rev Bras Epidemiol 2013; 16(3): 729-36. http://dx.doi.org/10.1590/S1415-790X2013000300016
https://doi.org/http://dx.doi.org/10.159... .

The study Nascer no Brasil (Being Born in Brazil) revealed a significantly higher risk of congenital syphilis among newborns whose mothers had less than eight years of schooling (3.2: 41.47 - 7.12), were black (3.17: 1.78 - 5.65), did not go to a single prenatal visit (6.07: 2.34 - 15.75), or received prenatal care in public health services (4.24: 2.07 - 8.69)¹⁶16. Domingues RMSM, Szwarcwald CL, Souza Junior PR, Leal M do C. Prevalence of syphilis in pregnancy and prenatal syphilis testing in Brazil: birth in Brazil study. Rev Saúde Pública 2014; 48(5): 766-74. http://dx.doi.org/10.1590/S0034-8910.2014048005114
https://doi.org/http://dx.doi.org/10.159... .

As expected, the results obtained from perinatal studies in Rio Grande showed, quite clearly, that pregnant women with a higher probability of not undergoing serological tests for syphilis had the same characteristics of puerperal women identified in the national study as those with greater risk of acquiring syphilis. This finding suggests that women who do not undergo this test during prenatal visits do not have it done in another location, which deepens the problem. In the case of Rio Grande, the total number of newborns exposed to congenital syphilis can reach 170 (6.5%), with 75 (2.9%) of them from mothers who went to at least one visit but did not have the test performed, and 90 (3.6%) whose mothers did not go to a single prenatal visit.

When interpreting these results, taking into account the type of study design adopted is essential, as it measures both exposures and the outcome at the same time. This scenario prevents the assessment of causality. Besides, it is important to consider that, in approximately half of the cases, the information about the performance of the serological test for syphilis was based only on the mother’s answers, without confirming the data in her records, which can lead to underreporting due to forgetfulness or the participant not mentioning it. These limitations, however, do not invalidate the results presented here, since cohort studies, which allow evaluating temporality, have amply shown the effects of demographic, socioeconomic, and reproductive variables, as well as those related to health service use on the numerous outcomes in maternal and child health. The possible underestimation of the non-performance of VDRL by the mother makes even more evident the need to implement actions aiming at increasing the coverage of the serological test for syphilis.

CONCLUSION

The timely diagnosis of syphilis during pregnancy is the main challenge for the control of congenital syphilis. It depends on universalizing care provision and eliminating missed opportunities²³23. Lafetá KR, Martelli-Júnior H, Silveira MF, Paranaíba LMR. Sífilis materna e congênita, subnotificação e difícil controle. Rev Bras Epidemiol 2016; 19(1): 63-74. http://dx.doi.org/10.1590/1980-5497201600010006
https://doi.org/http://dx.doi.org/10.159... . This study shows that this control is still not effective in the municipality of Rio Grande.

Our results indicate stagnation in the performance of serological tests for syphilis. They also reveal that women with lower socioeconomic status and a higher risk of complications during pregnancy and childbirth were more likely not to undergo this test. Efforts should be directed at reaching these pregnant women. In addition, we suggest the following measures to increase the coverage of the serological test for syphilis in this municipality:

ACKNOWLEDGMENTS

We thank the management of the University Hospital of the Universidade Federal do Rio Grande, the Irmandade Santa Casa de Misericórdia de Rio Grande, the Pastoral da Criança, the Municipal Secretariat of Health, and all who participated in these surveys.

References

Publication Dates

History