Evolution of prenatal detection of neural tube defects in the pregnant population of the city of Barcelona from 1992 to 2006.

OBJECTIVES: To assess the prenatal ultrasound detection rates (DR) of neural tube defects (NTDs) and its evolution over the 1992 to 2006 period in the pregnant population of the city of Barcelona. METHODS: Data on the population-based register of birth defects were used to assess the evolution of the prenatal DR for isolated NTD, including anencephaly, spina bifida and encephalocele by trimester of gestation. RESULTS: In the register, 127 isolated NTD cases, including 71 anencephalic fetuses, 49 spina bifidas and 7 encephaloceles were noted. Overall, prenatal ultrasound DR for isolated NTD was 94%. All fetuses with anencephaly or encephalocele were prenatally detected (100% DR), whereas DR for spina bifida was 84%, with no apparent variation over the observation period. An important increase in first trimester DRs was observed for anencephaly, rising from 16% in the first years of the study (1992-1996) to 71% in the last years (2002-2006). CONCLUSION: A high DR (94%) for isolated NTD was observed in the city of Barcelona. The single significant change across the study period was an increase in the first trimester DR for anencephaly (from 16% to 71%).

[Trends in social inequalities in pregnancy care in Barcelona (Spain), 1994-97 versus 2000-03]. / Evolución de las desigualdades según la clase social en el control del embarazo en Barcelona (1994-97 frente a 2000-03).

OBJECTIVE: To describe and compare social inequalities in pregnancy care among pregnant women living in Barcelona (Spain) in 2 periods. METHODS: Two 4-year periods were compared: 1994-1997 and 2000-2003. The study population consisted of pregnant women living in Barcelona and the control sample was drawn from the Barcelona Birth Defects Registry (n = 905 in 1994-1997; n = 927 in 2000-2003). Medical records and personal interviews with the mothers were used as information sources. The dependent variables were pregnancy planning, prenatal use of folic acid, smoking, the number of obstetric visits, trimester of the first visit, the number of obstetric ultrasound scans, fifth-month diagnostic ultrasound scan, invasive procedures, and smoking cessation. The independent variables were maternal age and social class. Maternal age-adjusted logistic regression models for each dependent variable according to social class were calculated and the results for both 4-year periods were compared. RESULTS: Pregnant women in both manual and non-manual occupational classes showed better results in the second period in 7 out of 10 variables (although the results were not identical in the 2 occupational classes). However, when interclass variations between the 2 periods were compared, differences in 8 out of 10 variables were found: 7 indicators were more favorable in the more privileged classes and only one was more favorable in the less privileged classes. CONCLUSIONS: Except for one of the variables analyzed (more than 3 ultrasound scans), the less privileged classes showed poorer results than the more privileged classes when the tendencies in indicators were compared between the two periods. The gap between social classes in pregnancy care is increasing over time.

Evolución de las desigualdades según la clase social en el control del embarazo en Barcelona (1994-97 frente a 2000-03) / Trends in social inequalities in pregnancy care in Barcelona (Spain), 1994-97 versus 2000-03

Objetivo: Describir y comparar las desigualdades según la clase social en el control del embarazo en Barcelona durante 2 períodos. Métodos: Se comparan 2 cuatrienios: 1994-1997 y 2000-2003. La población de estudio son las gestantes de Barcelona y la muestra los controles del Registro de Defectos Congénitos de Barcelona (n = 905 en 1994-1997; n = 927 en 2000-2003). Las fuentes de información son las historias hospitalarias y una encuesta realizada a las madres. Las variables dependientes son: planificación del embarazo, ingesta de ácido fólico antes del embarazo, consumo de tabaco, número de visitas al obstetra, trimestre de primera visita, número de ecografías, ecografía del quinto mes, prueba invasiva y abandono del tabaco. Las variables independientes son la edad y la clase social. Se ajustaron modelos de regresión logística para cada variable dependiente según la clase social y se compararon los resultados entre cuatrienios. Resultados: Tanto las gestantes de clases de ocupación manual como las de no manual presentan mejorías en el segundo cuatrienio en 7 de los 10 indicadores (no son exactamente los mismos en ambas clases). Sin embargo, cuando comparamos las variaciones interclase entre los 2 cuatrienios se registran diferencias en 8 de los 10 indicadores, 7 a favor de las clases más favorecidas y uno a favor de las menos favorecidas. Conclusiones: Excepto para una de las situaciones analizadas (hacer más de 3 ecografías), las clases menos favorecidas presentan peores resultados que las más favorecidas al comparar la tendencia de los indicadores entre los 2 períodos. La distancia entre clases en el ámbito del control de la gestación se acentúa con el tiempo

Objective: To describe and compare social inequalities in pregnancy care among pregnant women living in Barcelona (Spain) in 2 periods. Methods: Two 4-year periods were compared: 1994-1997 and 2000-2003. The study population consisted of pregnant women living in Barcelona and the control sample was drawn from the Barcelona Birth Defects Registry (n = 905 in 1994-1997; n = 927 in 2000-2003). Medical records and personal interviews with the mothers were used as information sources. The dependent variables were pregnancy planning, prenatal use of folic acid, smoking, the number of obstetric visits, trimester of the first visit, the number of obstetric ultrasound scans, fifth-month diagnostic ultrasound scan, invasive procedures, and smoking cessation. The independent variables were maternal age and social class. Maternal age-adjusted logistic regression models for each dependent variable according to social class were calculated and the results for both 4-year periods were compared. Results: Pregnant women in both manual and non-manual occupational classes showed better results in the second period in 7 out of 10 variables (although the results were not identical in the 2 occupational classes). However, when interclass variations between the 2 periods were compared, differences in 8 out of 10 variables were found: 7 indicators were more favorable in the more privileged classes and only one was more favorable in the less privileged classes. Conclusions: Except for one of the variables analyzed (more than 3 ultrasound scans), the less privileged classes showed poorer results than the more privileged classes when the tendencies in indicators were compared between the two periods. The gap between social classes in pregnancy care is increasing over time

Increasing detection rates of birth defects by prenatal ultrasound leading to apparent increasing prevalence. Lessons learned from the population-based registry of birth defects of Barcelona.

OBJECTIVE: To assess the evolving trends in prenatal ultrasound detection of birth defects and to suggest a method to avoid the bias generated by an increasing detection rate, when comparing different time periods. METHODS: In the population-based registry of birth defects of Barcelona (REDCB), 1976 cases with birth defects (1462 newborns and 514 terminations of pregnancy) were observed among 99 753 pregnancies, from 1992 to 1999. Detection rates for isolated birth defects by anatomical systems were evaluated. Since an increasing prevalence was observed in some birth defects systems, adjustment for detection rates was suggested. RESULTS: A rise in prevalence was observed in isolated birth defects involving internal organs (central nervous, respiratory, digestive, and urinary systems). Ultrasound detection rates increased in all system groups of isolated birth defects during the study period, except for cardiovascular defects. Early detection rates (before 23 weeks of pregnancy) increased in all but three systems (cardiovascular, genital and tegument). CONCLUSIONS: The apparent rise in the observed prevalence of certain birth defects may be largely due to improvements in prenatal detection methods. Population-based registries are able to measure the impact of evolving prenatal diagnosis in order to avoid biases and establish the prevalence of birth defects more accurately.