Objective: To compare outcomes from uterine ruptures (UR) among women without versus with a prior cesarean.
Method: This case-control study matched on gestational age +/- 1 week and birth year +/- 2 years using a variable numbers of controls (maximum = 4) for each case. All URs in Massachusetts between 1990 and 1998 were identified using ICD-9 codes from linked hospital discharge and birth/fetal death certificate files and confirmed by medical record review. Complete hospitalization records were abstracted. Maternal outcomes were hysterectomy, transfusion, ICU admission, shock, assisted ventilation, and hospital length of stay. Infant outcomes were 5 min Apgar less than 3 or need for ventilation at birth, death, or poor prognosis at discharge.
Results: The UR incidence in women without a prior cesarean was 7 per 100,000 births. Of the 49 women without a prior cesarean and a UR, 36 women met study criteria and were matched to 140 controls. Women without a prior cesarean had more severe maternal morbidity (50% vs. 16%) (adj OR 3.28, 95% CI: 1.70, 6.32) with 47% of cases requiring transfusion and 33% requiring ICU admission. Their hospital stays were nearly two days longer. Among their infants, 14% died or had a poor prognosis at discharge compared to 7% of control infants (OR = 2.42, 95% CI 0.94, 6.28).
Conclusion: Although UR in a woman without a prior cesarean is uncommon, providers should be prepared for more severe maternal morbidity which may be mitigated by prompt surgical intervention and heightened hemodynamic surveillance.