Unfavorable outcome in penultimate pregnancy and premature rupture of membranes in successive pregnancy.

OBJECTIVES: Previous adverse obstetric events are known to influence the outcome of the succeeding pregnancy. We tested the hypothesis that preterm premature rupture of membranes (PROM), full-term PROM, and preterm delivery without PROM relate independently to the outcome of the immediately preceding pregnancy.
METHODS: In a case-control study, 345 women 15-45 years old with preterm PROM, full-term PROM, or preterm delivery without PROM were singly matched by age, race, and parity to women having full-term delivery. Information about the penultimate pregnancy, household smoking, and sociodemographic variables were obtained during face-to-face interviews. Obstetric history, infections during pregnancy, and pregnancy complications abstracted from medical records were cross-checked with patient interview data. Penultimate pregnancy outcomes included full-term delivery, premature delivery, fetal loss or miscarriage, and planned abortion.
RESULTS: Women having preterm PROM or preterm delivery without PROM in the index pregnancy were, respectively, 6.34 and 21.28 times more likely than controls to have had preterm delivery in the preceding pregnancy. A preceding fetal loss or miscarriage also increased 4.39-fold the risk for preterm PROM. Exposure to cigarette smoke, urinary tract infections, and vaginal bleeding during the index pregnancy independently increased the risk for preterm PROM. Women with full-term PROM did not differ significantly from controls in the outcomes of the penultimate pregnancy.
CONCLUSION: Preterm delivery in the preceding pregnancy is associated with an increased risk for preterm delivery with or without PROM.