Maternal Morbidity After Previable Prelabor Rupture of Membranes

To identify risk factors for maternal morbidity after previable prelabor rupture of membranes (PROM).

We conducted a case-control study of singleton and twin pregnancies complicated by previable PROM (14.0-22.9 weeks of gestation) at a single tertiary care referral institution, 2000-2015. Pregnancies complicated by fetal anomalies, previable PROM within 2 weeks of chorionic villus sampling or amniocentesis, and those with contraindications to expectant management (eg, chorioamnionitis) were excluded. Cases were women with the primary outcome of composite maternal morbidity (defined as having at one or more of the following: sepsis, intensive care unit admission, acute renal insufficiency, uterine curettage, hysterectomy, deep vein thrombosis, pulmonary embolus, blood transfusion, readmission, or maternal death). Controls were women without the primary composite morbidity. Bivariate analysis compared demographic, clinical, and management characteristics of women in the case group and those in the control group. Multivariable logistic regression models were developed to quantify the association between maternal characteristics and composite severe maternal morbidity.

During the study period, 174 women presented with by previable PROM and were candidates for expectant management. Sixty-five (37%) women opted for immediate delivery; 109 (63%) elected expectant management. Twenty-five of 174 (14%) experienced one or more components of the composite maternal morbidity (cases) and were compared with 149 (86%) women in the control group. Women in the case group were more not more likely to elect expectant management (68% compared with 59%, P=.40), but were more likely to be aged 35 years or older (40% compared with 14%, P=.002) or to be carrying twins (52% compared with 16%, P<.01). In the regression model, twin gestation and age 35 years or older were both significantly associated with increased odds of composite maternal morbidity (odds ratio [OR] 5.62, 95% confidence interval [CI] 2.21-14.3 and OR 4.00, 95% CI 1.48-10.8, respectively).

Antenatal counseling of women with previable PROM should include that one in seven women experience significant morbidity. Although expectant management was not associated with increased risk in this cohort, women with twins or those aged 35 years or older were at substantially increased risk.