Trends in prevalence of gastroschisis in Brazil from 2007 to 2020: A national population‐based cross‐sectional study

Background Gastroschisis is a congenital abnormality of the abdominal wall which worldwide prevalence is increasing with time. Up to now, young maternal age is the main factor associated with gastroschisis. Brazil has a great proportion of adolescent mothers. Objectives To estimate prevalence of gastroschisis in Brazil, explore the effect of very young maternal age, and analyze regional distribution and time trends. Methods Cross‐sectional population‐based study using data from official national information systems from 2007 to 2020, covering 9,831 gastroschisis cases. Low maternal age was assessed as risk factor through odds ratio. Prevalence time trends by maternal age and geographic area were analyzed using joinpoint regression. Results Overall prevalence of gastroschisis in Brazil was 2.47 per 10,000 births. From first to last biennium, there was a 23% relative increase. Last biennium prevalence was higher in the Central‐west region and lower in the Northeast. Compared to mothers of 20–34 years old (YO), the odds‐ratio for prevalence and 95% confidence intervals for gastroschisis were, as follows: (a) 10–14 YO—4.9 (4.3,5.5); (b) 15–19 YO—3.6 (3.5,3.8); and (c) 35–49 YO—0.3 (95% CI 0.3, 0.4). Conclusions Prevalence of gastroschisis in Brazil relatively increased 23% from 2007 to 2020. This happened in all maternal age groups. Differences between regions may be associated to data quality. Young mothers had a higher prevalence of gastroschisis and still higher for those under 15 YO. Mother age over 34 YO was a protective factor.