Maternal fecal elastase-1 levels are lower in pregnancies with intrauterine growth restriction

Intrauterine growth restriction (IUGR) is a major cause of perinatal morbidity and mortality. Although placental insufficiency is considered the principal mechanism, maternal physiological factors influencing fetal growth remain incompletely understood. Maternal digestive physiology has received little attention in this context. Fecal elastase-1 (FE-1) is a non-invasive biomarker reflecting pancreatic enzyme secretion.

To explore whether maternal FE-1 concentrations differ between pregnancies complicated by IUGR and those with normal fetal growth.

In this prospective case-control study, 50 pregnancies with IUGR were compared with 50 gestational age-matched controls. FE-1 concentrations were measured using ELISA. Group comparisons, correlation analyses, multivariable logistic regression, and receiver operating characteristic (ROC) analysis were performed.

Median FE-1 levels were lower in the IUGR group than in controls (315 µg/g [IQR 180-546] vs. 461 µg/g [IQR 240-720]; p = 0.030). FE-1 concentrations below 200 µg/g were more frequent among IUGR pregnancies (30.0% vs. 12.0%, p = 0.027). In multivariable analysis, higher FE-1 levels were independently associated with lower odds of IUGR (OR 0.79 per 100 µg/g increase; 95% CI 0.64-0.97; p = 0.027). FE-1 concentrations were not significantly correlated with fetal biometric parameters. ROC analysis showed modest discriminative ability (AUC 0.625, 95% CI 0.516-0.734).

Pregnancies complicated by IUGR were associated with relatively lower maternal FE-1 concentrations compared with gestational age-matched controls. These findings should be interpreted as exploratory and hypothesis-generating rather than evidence of a causal relationship. Further studies incorporating nutritional biomarkers and detailed assessments of maternal digestive function are needed to clarify the underlying mechanisms.