Your Water Breaks First - A Date to PROM (Premature Rupture of Membranes) - Results From the Evidence Based Studies

Article Index

Scientific research data on term PROM comes from five primary sources.

  1. Research studies done in the 50’s|60’s.
    • This data is problematic because of various reasons, most of which can be attributed to the fact that these results were a product of their day and age. A limited list includes, antibiotics were relatively new and were not as popular as they are today, usually administered only after symptoms became severe, GBS was not known, understood or treated for, term PROM was not separated from Pre-term PROM, more than half of the women in these studies were “charity cases” who presented at hospital long after their membranes had ruptured and had received little to no prenatal care, and more importantly, these studies did not take into count the number of vaginal exams, one of the most important risk factors.
  2. Most of the data comes from a famous term PROM trial done in 1996. Hannah et. al.
    • The authors of this study concluded, “Induction of labor with intravenous oxytocin, induction of labor with vaginal prostaglandin E2 gel, and expectant management are all reasonable options for women and their babies if membranes rupture before the start of labor at term, since they result in similar rates of neonatal infection (2% -3% across all groups) and cesarean section (13.7% - 15.2% for 1st time mothers and 4.3%-4.6% for women who had given birth before across all groups).”
    • Women who were immediately induced with Pitocin were less likely to be clinically diagnosed with chorioamnionitis, compared to those who waited up to four days before being induced with Pitocin (4% versus 8.6%). There were no other significant differences across the remaining groups (induced immediately with prostaglandins versus waited up to four days before being induced with prostaglandins) at 6.2% versus 7.8%. The overall chorioamnionitis rate was 6.7%.
    • The problems with this study include but are not limited to the following:
      • the failure to consider the effect of epidural analgesia on intrapartum fever confounds the chorioamnionitis results.
      • Women who where GBS positive were not treated in labor. There were a total of 4 neonatal fatalities during this study and untreated GBS was the cause of one recorded death.
      • Chorioamnionitis rates already confounded by epidural use were further confounded by multiple digital vaginal exams. A secondary analysis of this data showed that the rate of chorioamnionitis increased steadily with the number of vaginal exams.
      • The confusion and controversy over what a clinical diagnosis of chorioamnionitis even meant in these studies and how many cases resulted in actual pathological diagnoses of chorioamnionitis versus how many were actually the “result” of one or more confounding factor.
      • In light of today’s stricter guidelines regarding this diagnosis, the coming changes in terminology, and other confounding factors is it very likely that the Term PROM researchers over diagnosed patients in regards to chorioamnionitis.
      • Neonatal results were confounded by digital vaginal exams at entry of the trial. These babies had a much higher rate of infection.
      • Neonatal results were confounded by multiple digital vaginal exams during labor.
  3. A Cochrane Systematic review done in 2006 that evaluated term PROM management, the reviewers reached a tempered conclusion. “Since differences in outcomes between planned and expectant management [induction vs waiting] may not be substantial, women need to be able to access the appropriate information to make an informed choice.” (Dare, 2006, p.12)
  4. The Pintucci PROM research study done more recently in 2014.
    • The results from this study are important because it was the first study to look at women who had modern testing and treatment for Group B Strep.
    • Researchers found that by screening for GBS, the overall rate of chorioamnionitis was 1.2% and included many women who waited for labor to begin on its own.
    • The women in the study who waited for labor to start on its own, waited in hospital and the study results showed that this group of women was able to “wait” with very good outcomes for both mothers and babies.
  5. In 2017, researchers at the Cochran database conducted a systematic review of studies that compared immediate induction with expected management, it found that the quality of evidence used to support inducing labor as a means of reducing risk of maternal infection and probable neonatal infection remains of very low to moderate quality. This review further states that “women should be appropriately counseled in order to make an informed choice between planned early birth and expectant management for PROM at 37 weeks’ gestation or later.”
    • Bearing in mind the general low quality of evidence, induction may mean:
      • Shorter duration from PROM to birth
      • less likely to experience a maternal infection (low quality evidence)
      • no increase in the risk of Cesarean (low quality evidence)
      • babies less likely to need antibiotics after birth
      • babies less likely to be admitted to NICU
      • both mother and babies had shorter hospital stays
    • There were no differences between induction and expectant management groups for:
      • serious maternal infection (very low quality evidence)
      • definite newborn infection (very low quality evidence)
      • perinatal mortality (moderate quality evidence)

It was a conclusion of all of these studies and reviews that in the absence of signs of infection, expectant management remains a viable option as long as a mother is properly counseled regarding the risks of prolonged PROM.