Premature Rupture of Membranes: What Have We Learned Since 2007?

Premature Rupture of Membranes

Preterm delivery occurs in approximately 12% of all births in the United States and is a major factor that contributes to perinatal morbidity and mortality (1,2). Preterm premature rupture of membranes (PROM) complicates approximately 3% of all pregnancies in the United States (3). The optimal approach to clinical assessment and treatment of women with term and preterm PROM remains controversial. Management hinges on knowledge of gestational age and evaluation of the relative risks of delivery versus the risks of expectant management (eg, infection, abruptio placentae, and umbilical cord accident). The purpose of this document is to review the current understanding of this condition and to provide management guidelines that have been validated by appropriately conducted outcome-based research when available. Additional guidelines on the basis of consensus and expert opinion also are presented.

Used with permission. Copyright the American College of Obstetricians and Gynecologists.

ACOG Practice Bulletin No. 139: Premature Rupture of Membranes, October 2013 Obstet Gynecol 2013;122;918-30. Full text of ACOG Practice Bulletin available to ACOG members at http://www.acog.org/Resources_And_Publications/Practice_Bulletins/Committee_on_Practice_Bulletins_--_Obstetrics/Premature_Rupture_of_Membranes

References

1. Martin JA, Hamilton BE, Ventura SJ, Osterman MJ, Wilson EC, Mathews TJ. Births: final data for 2010. Natl Vital Stat Rep 2012;61(1):1-71. (Level II-3)

2. Mathews TJ, MacDorman MF. Infant mortality statistics from the 2006 period linked birth/infant death data set. Nat Vital Stat Rep 2010;58:1-31. (Level II-3)

3. Waters TP, Mercer B. Preterm P:ROM: prediction, prevention, principles. Clin Obstet Gynecol 2011;54:307-12. (Level III)

Commentary

PROM: What have we learned since 2007?

By Sarah J. Kilpatrick, MD, PhD

Dr. Kilpatrick is the Helping Hand Endowed Chair, Department of Obstetrics and Gynecology, Cedars-Sinai Medical Center, Los Angeles, California, and a member of the Contemporary OB/GYN Editorial Board.

Practice Bulletin Number 139 replaced a 2007 Practice Bulletin and a 2011 Committee Opinion.¹ Not much has changed regarding the incidence or diagnosis of PROM, so what prompted this new document?

Six new questions or recommendations were addressed:

1. Should expectant management of preterm premature rupture of membranes (PPROM) continue after 34 weeks’ gestation?

2. Should a cerclage be removed after PPROM?

3. Should women with PPROM receive antenatal steroids between 32 and 34 weeks’ gestation just like those with other risks for imminently delivering preterm?

4. Should women with PPROM receive a rescue course of antenatal steroids?

5. Should antenatal magnesium sulfate for neuroprotection be recommended for women with PPROM?

6. What should be offered to women with a history of PPROM in their subsequent pregnancy?

The standard recommendation-that women with PPROM and no other indications for delivery should be delivered at 34 weeks-stemmed from retrospective studies suggesting that risk of infection to mother and neonate outweighed the prematurity risks by 34 weeks. Recent studies have questioned this principle and suggest that expectant management between 34 and 37 weeks’ gestation was not associated with a significant increase in neonatal infection.^2,3 However, the same studies reported a significant increase in chorioamnionitis in the expectant group.

Based on these results, the American College of Obstetricians and Gynecologists (ACOG) reaffirmed its position to recommend induction at 34 weeks’ gestation in women with PPROM. 

Cerclage after PPROM

How to manage a cerclage after PPROM is a difficult issue because data are insufficient to recommend either retention or removal, which is exactly what the current Practice Bulletin concludes. That conclusion is similar to the 2007 Practice Bulletin. However, the results of a randomized trial published this year provide little additional guidance because it was stopped before it reached its intended power.⁴ No significant difference in latency to delivery was found between women with cerclage retention and those with cerclage removal (mean 9 vs 13 days, respectively). Chorioamnionitis occurred in 42% of the women with retained cerclage versus 25% of those in whom a cerclage was removed. Although that difference was not significant, there is always the possibility of a type 2 error (ie, accepting a null hypothesis that is false).

Likewise, there was no difference in neonatal composite morbidity with incidences of 56% and 50%, respectively, in neonates born to women with retained cerclages versus removed cerclages. I have always removed cerclages in women with PPROM based on the earlier data regarding a possible association with increase in neonatal death and infection,^5,6 and this new randomized trial supports this approach.^4-6

Antenatal steroids and magnesium sulfate

Just as for any woman at risk of imminent preterm delivery, a course of antenatal steroids was recommended for women with PPROM 24 0/7 – 34 0/7 weeks’ gestation. That is a change from the 2011 Committee Opinion, which recommended antenatal steroids only for women with PPROM before 32 weeks’ gestation, based on lack of efficacy data between 32 and 34 weeks in PPROM.

The new guidance, of course, makes the general antenatal steroid recommendation much simpler: Treat all women likely to deliver imminently before 34 weeks with antenatal steroids to improve neonatal outcome. Data are insufficient to make a recommendation as to whether women with PPROM should receive a rescue course.

The concept that antenatal magnesium sulfate is associated with a reduced risk of cerebral palsy (CP) is also new since the last Practice Bulletin on PROM. The largest randomized trial, reporting a significant reduction in CP in the children of mothers who received antenatal magnesium sulfate, included a large proportion of women with PPROM.⁷ Therefore, ACOG recommended (Level A) that women with PPROM likely to deliver before 32 0/7 weeks’ gestation, just like women at risk of imminent preterm delivery without ruptured membranes, should be candidates for magnesium sulfate for neuroprotection.

Like women with prior spontaneous preterm delivery, those with a history of prior PPROM are at increased risk of subsequent preterm delivery. Women with a history of PPROM were included in the randomized trials of progesterone for reduction of subsequent preterm delivery and they are candidates for progesterone treatment beginning at 16 to 24 weeks’ gestation in a subsequent pregnancy.⁸

Obstetric principles

Interesting affirmations of basic obstetric principles also appear in this Practice Bulletin. We are reminded to allow sufficient time (12-18 hours) for latent labor to progress before proceeding with a failed induction in women induced at term with PPROM.

This is a timely reminder, given our national efforts to decrease the rate of nulliparous term singleton vertex cesarean delivery. We are reminded to avoid digital exams in women with PPROM who are not in labor. And, we are reminded that there is no consensus or reasonable data to direct the frequency of fetal assessment or assessment for infection in women with viable PPROM.

So, in this time of medicine moving toward value-based care, perhaps we should minimize if not eliminate any routine laboratory evaluation of women with asymptomatic PPROM?

This Practice Bulletin recommends proceeding with induction because in randomized trials and meta-analysis, induction was associated with reduced time to delivery and reduced chorioamnionitis.^9,10 However, the Practice Bulletin states that expectant management may be appropriate if a patient declines induction, and she is informed of the potential increased risks of delayed delivery.

There continues to be recommendation for delivery at 34 weeks’ gestation in women with PPROM. However, the Practice Bulletin goes on to state that if expectant management is undertaken after 34 weeks, then the risk: benefit balance should be considered and discussed with the patient, and delivery should not be delayed past 37 weeks.

References

1. American College of Obstetricians and Gynecologists. Practice Bulletin No. 139: Premature rupture of membranes. Obstet Gynecol. 2013;122:918-930.

2. van der Ham DP, van der Heyden JL, Opmeer BC, Mulder AL, Moonen RM, van Beek JH, et al. Management of late-preterm premature rupture of membranes: the PPROMEXIL-2 trial. Am J Obstet Gynecol. 2012;207:276.

3. van der Ham DP, Vijgen SM, Nijhuis JG, van Beek JJ, Opmeer BC, Mulder AL, et al. Induction of labor versus expectant management in women with preterm prelabor rupture of membranes between 34 and 37 weeks: a randomized controlled trial. PPROMEXIL trial group. PLoS Med. 2012;9:e1001208.

4. Galyean A, Garite TJ, Maurel K, Abril D, Adair CD, Browne P, et al. Removal versus retention of cerclage in preterm premature rupture of membranes: a randomized controlled trial. Am J Obstet Gynecol. 2014 [Epub ahead of print].

5. Giraldo-Isaza MA, Berghella V. Cervical cerclage and preterm PROM. Clin Obstet Gynecol. 2011;54:313–320.

6. Laskin MD, Yinon Y, Whittle WL. Preterm premature rupture of membranes in the presence of cerclage: is the risk for intra-uterine infection and adverse neonatal outcome increased? J Matern Fetal Neonatal Med. 2012;25:424–428.

7. Rouse DJ, Hirtz DG, Thom E, Varner MW, Spong CY, Mercer BM, et al. A randomized, controlled trial of magnesium sulfate for the prevention of cerebral palsy. Eunice Kennedy Shriver NICHD Maternal-Fetal Medicine Units Network. N Engl J Med. 2008;359:895–905.

8. Meis PJ, Klebanoff M, Thom E, Dombrowski MP, Sibai B, Moawad AH, et al. Prevention of recurrent preterm delivery by 17 alpha-hydroxyprogesterone caproate. National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network [published erratum appears in N Engl J Med 2003;349:1299]. N Engl J Med. 2003;348:2379–2385.

9. Hannah ME, Ohlsson A, Farine D, Hewson SA, Hodnett ED, Myhr TL, et al. Induction of labor compared with expectant management for prelabor rupture of the membranes at term. TERMPROM Study Group. N Engl J Med. 1996;334:1005–1010.

10. Dare MR, Middleton P, Crowther CA, Flenady V, Varatharaju B. Planned early birth versus expectant management (waiting) for prelabour rupture of membranes at term (37 weeks or more). Cochrane Database of Systematic Reviews. 2006, Issue 1. Art. No.: CD005302. DOI: 10.1002/14651858.CD005302.pub2.