Perinatal Outcomes and Influence of Amniotic Fluid Volume Following Previable, Preterm Prelabor Rupture of Membranes (pPPROM): A Historical Cohort Study

Abstract

Purpose To determine perinatal outcomes and influence of amniotic fluid volume in pregnancies complicated by previable, preterm prelabor rupture of membranes (pPPROM). Patients and methods This was a historical cohort study from two tertiary-level maternity hospitals (January 1, 2009 to December 31, 2015). All pregnancies complicated by pPPROM were identified using ICD coding of discharge abstracts. Hospital charts were reviewed to collect maternal demographics, pregnancy and delivery events, and immediate postnatal outcomes (including survival). Post-processing review of stored ultrasound images was performed to evaluate the relationship between amniotic fluid volume and outcomes. Results A total of 113 pregnancies were eligible and 99 were included in the final analysis (74 with “expectant management” and 25 opting for elective termination). The median gestational age at pPPROM was 20+6 weeks [IQR 19+4 to 21+5]. For those choosing expectant management, the median latency between pPPROM and delivery was 7 days, median gestational at delivery was 23+1 weeks, and neonatal survival to discharge was 27.5% overall. There was a trend towards higher rates of pregnancy termination at one hospital (31.7%) compared to the other (15.4%), but no difference between sites with respect to latency, mode of delivery, or survival amongst those managed expectantly. There was a relationship between survival and gestational age at pPPROM ( p <0.04), as well as initial amniotic fluid volume category: 52.6% of survivors had normal initial amniotic fluid volumes whereas the majority of previable losses had oligohydramnios and the majority of stillbirths had anhydramnios. Conclusion After expectant management, more than one in four newborns following pPPROM survived to hospital discharge. While gestational age at rupture was most strongly correlated with survival, normal initial amniotic fluid volumes were mostly seen in survivors whereas stillbirths more frequently had anhydramnios. These findings will help to improve counseling and care of patients with pPPROM and in guiding long-term follow-up studies.

Early Neurodevelopmental Outcomes after Previable Preterm Prelabour Rupture of Membranes (pPPROM)

“…This was a secondary analysis of a subset of infants born between January 1, 2009, and December 31, 2015, following pPPROM from a previously published retrospective cohort [ 10 ]. Those infants presenting to a regional neonatal follow-up clinic with stored developmental outcomes at 18–24 months CA (June 1, 2011 to December 31, 2017) were eligible for inclusion.…”

“…From the original cohort of pregnant patients diagnosed with pPPROM prior to 24 + 0 weeks of gestation during the study period, those neonates surviving to hospital discharge were assessed for possible inclusion [ 10 ]. To start, all pregnancies complicated by PPROM had been identified using the International Classification of Disease–Ninth Revision (ICD-9) coding by hospital discharge abstracts [ 10 ].…”

“…Low amniotic fluid is associated with adverse outcomes, but the association between amniotic fluid volumes and developmental outcomes is currently unknown [ 10 – 12 ]. For instance, there was a higher frequency of stillbirth and previable delivery with complete anhydramnios postrupture [ 10 ]. In another study, a minimum single deepest vertical pocket of at least 1 centimeter or more was associated with longer latency and greater neonatal survival [ 11 ].…”

“…In another study, a minimum single deepest vertical pocket of at least 1 centimeter or more was associated with longer latency and greater neonatal survival [ 11 ]. There was also a higher risk of caesarean section, postpartum hemorrhage, and maternal sepsis after pPPROM [ 7 , 10 ]. However, less is known about the long-term, postnatal outcomes of neonates following pPPROM.…”

“…There are also challenges with ascertaining whether the intrauterine infection precedes membrane rupture or follows as a consequence of ascending infection through an opening in the membranes. In our original study with over 113 cases of pPPROM, there were higher rates of chorioamnionitis in the expectant management group versus those undergoing termination, suggesting that not all cases of preterm membrane rupture necessarily occur as a consequence of infection [ 10 ]. While latency does seem to be associated with risk of chorioamnionitis, one study did not find any obvious difference in prevalence of severe impairment by categorical latency duration of greater that 3 weeks (versus <3 weeks) [ 17 ].…”