Predictors for prolonged interval from premature rupture of membranes to spontaneous onset of labor at term

Prevalence of term prelabor rupture of membranes and factors associated with a longer interval of rupture: data from the 2021 French national perinatal survey

OBJECTIVES

Term prelabor rupture of membranes (term PROM) increases maternal and neonatal morbidity, but its current prevalence is unknown. This study aimed to estimate the prevalence of term PROM and to identify factors associated with a longer interval of rupture of membranes using recent national population-based data.

STUDY DESIGN

Women with singleton pregnancies and term deliveries from the 2021 French National Perinatal Survey were selected. The prevalence of term PROM, defined as the rupture of membranes from 37 weeks before spontaneous labor, and its 95 % confidence interval (CI) were estimated. The median interval of rupture, defined as the time between the rupture of membranes and the onset of spontaneous labor, induction or prelabor caesarean (whichever occurred first) was calculated. Sociodemographic and pregnancy factors related to a longer interval of rupture of membranes were analyzed using a survival analysis, adjusting for competitive risks of a spontaneous labor: induction of labor and prelabor cesarean. Adjusted Hazard Ratios (aHR) were calculated using multivariate analysis.

RESULTS

Among 10,810 eligible women, 3,052 had a term PROM, yielding a prevalence of 28.2 % (95 %CI 27.4-29.1). The median interval of rupture was 8.3 h (Interquartile 25-75[3.5-21.3]). Within the first 24 h following PROM, 90 % of women with a spontaneous labor were in labor. Factors associated with a longer interval of rupture included maternal age ≥35 (aHR = 0.82 95 %CI 0.72-0.93), primiparity (aHR = 0.73 95 %CI 0.66-0.81), Body-mass Index ≥25 (aHR = 0.87 95 %CI 0.77-0.97) or ≥30 (aHR = 0.73 95 %CI 0.62-0.85), being single (aHR = 0.66 95 %CI 0.48-0.90) and lower education (aHR = 0.82 95 %CI 0.69-0.97).

CONCLUSIONS

Term PROM affects more than one in four women. Sociodemographic factors and parity are associated with a longer interval of rupture.

Diagnostic value of Chorioquick for detecting chorioamnionitis in women with premature rupture of membranes

OBJECTIVE

To determine the accuracy of a semi-quantitative interleukin-6 (IL-6) vaginal secretion rapid test (Chorioquick) for detecting chorioamnionitis in women with premature rupture of membranes (PROM).

METHODS

A prospective cohort study in five tertiary hospitals in Nigeria involved women with confirmed PROM at term and preterm PROM with or without suspected chorioamnionitis from August 1, 2017, to October 31, 2018. Cervicovaginal fluid samples were tested for chorioamnionitis using the Chorioquick test. Samples were repeated at decision to deliver. The test was considered positive if at least the indicator 'IL-6 low' of the three Chorioquick biomarkers (low, medium, high) was positive, or negative if none of the biomarkers were positive. Chorioamnionitis was histologically confirmed post-delivery using three tissue samples. Primary outcome measures were sensitivity, specificity, and accuracy.

RESULTS

Of 73 women, on histological confirmation, 39 were true positive and 29 were true negative (for chorioamnionitis) to the Chorioquick test at repeat assessment. Overall, the Chorioquick test had a sensitivity of 97.5% (95% confidence interval [CI] 85.3-99.9), specificity 87.9% (70.9-96.0), and accuracy 93.2% (79.5-99.1). Sub-group analysis of women <37 weeks of pregnancy showed a sensitivity of 100.0% (95% CI 83.4-100.0), specificity of 91.3% (70.5-98.5), and accuracy of 95.8% (82.5-99.5). Triple positive samples were 100.0% specific in all gestations.

CONCLUSION

Chorioquick showed favorable utility for detecting chorioamnionitis in PROM and could be a reliable, non-invasive rapid tool in a real-world clinical setting.

[Term Prelabor Rupture of Membranes: CNGOF Guidelines for Clinical Practice - Definition, Epidemiology, Complications and Risk Factors]

OBJECTIVE

To synthesize current knowledge on definition, frequency, morbidity and risk factors related to term prelabor rupture of membranes.

METHODS

The MedLine database, the Cochrane Library and French and foreign guidelines from 1980 to 2019 have been consulted.

RESULTS

Term rupture of membranes is defined by the rupture of the membranes after 37 weeks of gestation (WG). Term prelabor rupture of membranes is defined by the rupture of membranes prior to the onset of labor after 37 WG. According to unpublished data from the 2016 French National Perinatal Survey, 26,5% of women with singleton pregnancies had a term rupture of membranes before their admission into labor ward. We were not able to assess if those were "prelabor" or not (LE3). Among women admitted with term rupture of membranes, 35,6% were still not in labor 12hours after the rupture i.e. 8,9% of all singleton pregnancies (LE3). Reported rates of term prelabor rupture of membranes vary between 6 and 22% in singleton pregnancies (LE3). Term prelabor rupture of membranes is associated with a risk of fever before (LE3), during (LE3) and after labor (LE3), as well as intrauterine and neonatal infection (LE3). The frequency of these complications in the context of a routine antibiotic prophylaxis is unknown. The expert group chose a delay of 12hours without spontaneous labor to differentiate a physiological situation from a potentially risky situation that could justify a medical intervention (Professional consensus). Risk factors for term prelabor rupture of membranes include history of term prelabor rupture of membranes (LE3), nulliparity (LE3), uterine contractions requiring treatment (LE3) and first trimester bleeding (LE3).

CONCLUSION

Data on frequency, risk factors and morbidity of term prelabor rupture of membranes are limited or of poor quality.

Performance indices of AmnioQuick Duo+ versus placental α-microglobulin-1 tests for women with prolonged premature rupture of membranes

OBJECTIVE

To compare AmnioQuick Duo+ versus the placental α-microglobulin-1 (PAMG-1) test for diagnosis of prolonged premature rupture of membranes (PROM).

METHODS

A multicenter prospective cohort study included women with suspected PROM at six tertiary institutions in southern Nigeria between January 1 and December 31, 2015. The inclusion criteria were features of PROM lasting at least 24 hours and a pregnancy duration of more than 24 weeks. AmnioQuick Duo+ (Biosynex, Strasbourg, France) and PAMG-1 (AmniSure International, Boston, USA) tests were used to diagnose PROM, which was confirmed after delivery by any two of the following criteria: delivery within 48 hours to 7 days, chorioamnionitis, membranes perceptibly ruptured at delivery, and adverse perinatal outcomes considerably associated with prolonged PROM.

RESULTS

Of 100 women assessed for eligibility, 99 were included. Sensitivity, specificity, and accuracy were, respectively, 97.3%, 100%, and 95.9% for AmnioQuick Duo+, and 93.2%, 100%, and 90.4% for PAMG-1. The differences were not significant and the diagnostic discordant rate between the two tests was 3.1%. In equivocal cases (i.e., negative pooling test result), AmnioQuick Duo+ and PAMG-1 performed equally (diagnostic accuracy, 100% vs 97.7%; P>0.99).

CONCLUSION

For diagnosis of PROM, AmnioQuick Duo+ was found to be non-inferior and comparable in accuracy to the PAMG-1 test, with a diagnostic discordance rate of 3.1%.