OBJECTIVE The study of soluble corin in the circulation before hypertensive disorders of pregnancy (HDP) has been limited. Here we aimed to study serum soluble corin in mid pregnancy in patients with HDP and their age- and gestational weeks-matched controls.   
 METHODS Sixty-eight pairs of cases of HDP and controls were studied. Blood samples were obtained in mid pregnancy between 16 and 20 gestational weeks. Serum soluble corin was examined by enzyme-linked immunosorbent assay methods. The relationship between serum soluble corin and HDP was examined using conditional logistic regression models.   
 RESULTS Serum soluble corin in mid pregnancy was increased in cases with HDP compared with controls (median [interquartile range]: 1968 [1644-2332] pg/mL vs. 1700 [1446-2056] pg/mL, p=0.002). Participants were categorized into quartiles of serum soluble corin distributed in controls. Compared with the lowest quartile, participants in the highest quartile had a significantly increased risk for HDP (odds ratio [OR], 4.21; 95% confidence interval [95% CI], 1.31-13.53) after multivariate adjustment. Nevertheless, we did not find a significantly increased risk for participants in the second (OR, 1.75; 95% CI, 0.44-7.02) and third (OR, 2.80; 95% CI, 0.70-11.18) quartiles. Then the first three quartiles were merged as a reference group to calculate the OR of HDP for participants in the highest quartile and we found a significantly increased risk for HDP in individuals in the highest quartile (OR, 2.28, 95% CI, 1.02-5.06).   
 CONCLUSION Increased serum soluble corin in mid pregnancy was associated with an increased risk for HDP. Our findings suggest that increased serum soluble corin in mid pregnancy could be an indicator for HDP.
True