Abstract
Purpose
The purpose of this study is to carry out a comparative analysis of Japanese women with and without sensitivity to cold (hiesho) during pregnancy with regard to incidence of premature rupture of membranes and infer the causal effects as to whether sensitivity to cold (hiesho) induces premature rupture of membranes.
Method
The study design was a retrospective cohort study. Data was collected for approximately twelve months between October 19, 2009 and October 8, 2010 at six general hospitals with obstetric and pediatric departments in the Greater Tokyo Metropolitan Area. The study was conducted on 2,810 postpartum Japanese women inpatients at those hospitals, and their information was extracted from questionnaire surveys and medical records. In this analysis, confounding factors were adjusted using propensity scores.
Results
Out of 662 women (23.6%) with premature rupture of membranes, 348 (52.6%) had sensitivity to cold (hiesho) and 314 (47.4%) did not. Incidence of premature rupture of membranes is 1.67 times higher (analysis of covariance) or 1.69 times higher (stratified analysis) among pregnant women with sensitivity to cold (hiesho) than those without sensitivity to cold (hiesho) (p<.001).
Conclusions
It was strongly inferred that causal effects exist between sensitivity to cold (hiesho) and premature rupture of membranes.
