The inverse association between gastroschisis and gestational hypertension

Abstract. Objective: Examine the relationship between maternal gestational hypertension (GH) and gastroschisis. Study design: This retrospective, observational study used a local dataset of 30 300 NICU patients and 3 429 498 U.S. birth certificate records to examine the prevalence of GH using univariate and logistic regression. Since body mass index (BMI) was not available in the data, we used Monte Carlo simulation of BMI followed by logistic regression to estimate the influence of this missing variable in the birth certificate data. Results: In the local dataset, maternal GH was lower in mothers of gastroschisis cases compared to the mothers of all other NICU admissions (0/188 vs. 4 351/30 112 [14.5%], p < 0.001). Adjusting for covariates, the odds ratio (OR) for GH among mothers of gastroschisis patients was 0.04 (95% confidence interval [CI] = 0.01–0.28, p = 0.001). In birth certificate data, GH was lower in mothers of gastroschisis cases compared to all others (22/927 [2.4%] vs. 144 521/3 428 571 [4.2%], p = 0.005). Adjustment for covariates and simulated BMI also showed a lower prevalence of GH in mothers of gastroschisis cases (OR = 0.58, 95% CI = 0.35–0.94, p = 0.005). Conclusion: Women delivering a live-born infant with gastroschisis may have a decreased prevalence of GH. This unique observation warrants additional confirmatory studies. Such studies might provide insight into both GH and gastroschisis.