Midtrimester preterm prelabour rupture of membranes (PPROM): expectant management or amnioinfusion for improving perinatal outcomes (PPROMEXIL - III trial)

Treatment of Classic Mid-Trimester Preterm Premature Rupture of Membranes (PPROM) with Oligo/Anhydramnion between 22 and 26 Weeks of Gestation by Means of Continuous Amnioinfusion: Protocol of a Randomized Multicentric Prospective Controlled TRIAL and Review of the Literature

Background: The classic mid-trimester preterm premature rupture of membranes (PPROM) is defined as a rupture of the fetal membranes prior to 28 weeks of gestation (WG) with oligo/anhydramnion; it complicates approximately 0.4–0.7% of all pregnancies and is associated with very high neonatal mortality and morbidity. Antibiotics have limited success to prevent bacterial growth, chorioamnionitis and fetal inflammation. The repetitive amnioinfusion does not work because fluid is lost immediately after the intervention. The continuous amnioinfusion through the transabdominal port system or catheter in patients with classic PPROM shows promise by flushing out the bacteria and inflammatory components from the amniotic cavity, replacing amniotic fluid and thus prolonging the PPROM-to-delivery interval. Objective: This multicenter trial aims to test the effect of continuous amnioinfusion on the neonatal survival without the typical major morbidities, such as severe bronchopulmonary dysplasia, intraventricular hemorrhage, cystic periventricular leukomalacia and necrotizing enterocolitis one year after the delivery. Study Design: We plan to conduct a randomized multicenter trial with a two-arm parallel design. Randomization will be between 22/0 and 26/0 SSW. The control group: PPROM patients between 20/0 and 26/0 WG who will be treated with antibiotics and corticosteroids (from 22/0 SSW) in accordance with the guidelines of German Society of Obstetrics and Gynecology (standard PPROM therapy). In the interventional group, the standard PPROM therapy will be complemented with the Amnion Flush Method, with the amnioinfusion of Amnion Flush Solution through the intra-amnial catheter (up to 100 mL/h, 2400 mL/day). Subjects: The study will include 68 patients with classic PPROM between 20/0 and 26/0 WG. TRIAL-registration: ClinicalTrials.gov ID: NCT04696003. German Clinical Trials Register: DRKS00024503, January 2021.

Prediction of adverse neonatal outcome among newborns born through meconium-stained amniotic fluid

OBJECTIVE

To study maternal and intrapartum factors associated with adverse neonatal outcome in deliveries complicated by meconium-stained amniotic fluid (MSAF).

METHODS

A retrospective cohort study of all women with singleton gestations undergoing trial of labor with MSAF during 2011-2020. Deliveries with adverse neonatal outcome were compared with deliveries without.

RESULTS

Overall, 11 329 were included; 376 (3.3%) neonates were diagnosed with adverse neonatal outcomes. Multivariable regression analysis underlined the following factors as independently associated with composite adverse neonatal outcome: pregestational diabetes (odds ratio [OR] 3.21, 95% confidence interval [CI] 1.09-9.43, P = 0.031), polyhydramnios (OR 2.14, 95% CI 1.33-3.44, P = 0.002), fever (OR 2.52, 95% CI 1.67-3.80, P < 0.001), and amnioinfusion (OR 1.73, 95% CI 1.24-2.2438, P = 0.003). When 0, 1, 2, and 3 of the independent risk factors identified were present, the rates of adverse neonatal outcome were 2.9%, 5.5%, 10.0%, and 100%, respectively.

CONCLUSION

The current study's results suggest that special attention should be payed to deliveries complicated by MSAF and with any of the following factors-polyhydramnios, intrapartum fever, amnioinfusion, and pregestational diabetes.

Is it safe to perform amnioinfusion in the presence of suspected intraamniotic infection?

OBJECTIVE

To study the effect of amnioinfusion in the presence of suspected intra-amniotic infections (SII) on maternal outcomes among women delivering at term.

METHODS

A retrospective cohort study was conducted at a tertiary medical center. All consecutive singleton term deliveries with SII during 2011-2019 were included. Cases where amnioinfusion was performed after the diagnosis of SII were compared to cases without amnioinfusion, matched by cervical dilation at diagnosis of SII. Maternal and obstetric adverse outcomes were compared.

RESULTS

After matching for cervical dilation at diagnosis of SII, the study cohort included 786 women: 62 (7.9%) women in the amnioinfusion group and 724 (92.1%) in the control group. A composite of adverse maternal outcomes occurred in 106 (13.5%) deliveries. There were no significant differences in the rates of maternal adverse outcomes between the amnioinfusion and control groups (11.0% vs 13.7%, respectively; P=0.59), including postpartum endometritis (5.0% vs 3.3%, respectively; P=0.46) and febrile morbidity (10.0% vs 6.5%, respectively; P=0.42). Neonatal blood gas outcomes and Apgar scores did not differ between groups.

CONCLUSION

The use of amnioinfusion for alleviating non-reassuring fetal heart rate in the presence of SII is safe and does not increase the rate of maternal adverse outcome.

Questionnaire survey on the management of pregnant women with preterm premature rupture of membranes

Objective

The aim of this survey was to study the status of the actual practice in the management of preterm premature rupture of membranes (PPROM) between 34.0 and 36.6 weeks of gestation.

Methods

This survey was designed for obstetricians who work in secondary or tertiary medical institutions and attended the Korean Society of Maternal Fetal Medicine conference held on July 1, 2017, in Korea, using a structured questionnaire consisting of 5 questions.

Results

The most commonly used antibiotic was cephalosporin monotherapy (34.5%). Antenatal corticosteroids were applied up to 34.0 weeks of gestation in half of the respondents. The frequency of expectant management was higher than that of immediate delivery in women with PPROM between 34.0 and 36.6 weeks of gestation (57.4%). The most important factor in determining immediate delivery was the symptoms of chorioamnionitis.

Conclusion

The present survey showed a considerable variation in the actual management of PPROM in women, especially the optimal timing of delivery. More evidenced-based studies with statistical power are required to decrease the heterogeneity of clinical practice.

Child outcomes after amnioinfusion compared with no intervention in women with second-trimester rupture of membranes: a long-term follow-up study of the PROMEXIL-III trial

OBJECTIVE

To assess the effect of transabdominal amnioinfusion or no intervention on long-term outcomes in children born after second-trimester prelabour rupture of the membranes (PROM between 16^+0/7 -24^+0/7  weeks) and oligohydramnios.

POPULATION

Follow up of infants of women who participated in the randomised controlled trial: PPROMEXIL-III (NTR3492).

METHODS

Surviving infants were invited for neurodevelopmental assessment up to 5 years of corrected age using a Bayley Scales of Infant and Toddler Development or a Wechsler Preschool and Primary Scale of Intelligence. Parents were asked to complete several questionnaires.

MAIN OUTCOME MEASURES

Neurodevelopmental outcomes were measured. Mild delay was defined as -1 standard deviation (SD), severe delay as -2 SD. Healthy long-term survival was defined as survival without neurodevelopmental delay or respiratory problems.

RESULTS

In the amnioinfusion group, 18/28 children (64%) died versus 21/28 (75%) in the no intervention group (relative risk 0.86; 95% confidence interval [CI] 0.60-1.22). Follow-up data were obtained from 14/17 (82%) children (10 amnioinfusion, 4 no intervention). In both groups, 2/28 (7.1%) had a mild neurodevelopmental delay. No severe delay was seen. Healthy long-term survival occurred in 5/28 children (17.9%) after amnioinfusion versus 2/28 (7.1%) after no intervention (odds ratio 2.50; 95% CI 0.53-11.83). When analysing data for all assessed survivors, 10/14 (71.4%) survived without mild neurodevelopmental delay and 7/14 (50%) were classified healthy long-term survivor.

CONCLUSIONS

In this small sample of women suffering second-trimester PROM and oligohydramnios, amnioinfusion did not improve long-term outcomes. Overall, 71% of survivors had no neurodevelopmental delay.

TWEETABLE ABSTRACT

Healthy long-term survival was comparable for children born after second-trimester PROM and treatment with amnioinfusion or no intervention.

Amnioinfusion Compared With No Intervention in Women With Second-Trimester Rupture of Membranes: A Randomized Controlled Trial

OBJECTIVE

To assess the effectiveness of amnioinfusion in women with second-trimester preterm prelabor rupture of membranes.

METHODS

We performed a nationwide, multicenter, open-label, randomized controlled trial, the PPROM: Expectant Management versus Induction of Labor-III (PPROMEXIL-III) trial, in women with singleton pregnancies and preterm prelabor rupture of membranes at 16 0/7 to 24 0/7 weeks of gestation with oligohydramnios (single deepest pocket less than 20 mm). Participants were allocated to transabdominal amnioinfusion or no intervention in a one-to-one ratio by a web-based system. If the single deepest pocket was less than 20 mm on follow-up visits, amnioinfusion was repeated weekly until 28 0/7 weeks of gestation. The primary outcome was perinatal mortality. We needed 56 women to show a reduction in perinatal mortality from 70% to 35% (β error 0.20, two-sided α error 0.05).

RESULTS

Between June 15, 2012, and January 13, 2016, we randomized 28 women to amnioinfusion and 28 to no intervention. One woman was enrolled before the trial registration date (June 19, 2012). Perinatal mortality rates were 18 of 28 (64%) in the amnioinfusion group vs 21 of 28 (75%) in the no intervention group (relative risk 0.86, 95% CI 0.60-1.22, P=.39).

CONCLUSION

In women with second-trimester preterm prelabor rupture of membranes and oligohydramnios, we found no reduction in perinatal mortality after amnioinfusion.

CLINICAL TRIAL REGISTRATION

NTR Dutch Trial Register, NTR3492.

Mid-trimester preterm premature rupture of membranes (PPROM): etiology, diagnosis, classification, international recommendations of treatment options and outcome

Mid-trimester preterm premature rupture of membranes (PPROM), defined as rupture of fetal membranes prior to 28 weeks of gestation, complicates approximately 0.4%-0.7% of all pregnancies. This condition is associated with a very high neonatal mortality rate as well as an increased risk of long- and short-term severe neonatal morbidity. The causes of the mid-trimester PPROM are multifactorial. Altered membrane morphology including marked swelling and disruption of the collagen network which is seen with PPROM can be triggered by bacterial products or/and pro-inflammatory cytokines. Activation of matrix metalloproteinases (MMP) have been implicated in the mechanism of PPROM. The propagation of bacteria is an important contributing factor not only in PPROM, but also in adverse neonatal and maternal outcomes after PPROM. Inflammatory mediators likely play a causative role in both disruption of fetal membrane integrity and activation of uterine contraction. The "classic PPROM" with oligo/an-hydramnion is associated with a short latency period and worse neonatal outcome compared to similar gestational aged neonates delivered without antecedent PPROM. The "high PPROM" syndrome is defined as a defect of the chorio-amniotic membranes, which is not located over the internal cervical os. It may be associated with either a normal or reduced amount of amniotic fluid. It may explain why sensitive biochemical tests such as the Amniosure (PAMG-1) or IGFBP-1/alpha fetoprotein test can have a positive result without other signs of overt ROM such as fluid leakage with Valsalva. The membrane defect following fetoscopy also fulfils the criteria for "high PPROM" syndrome. In some cases, the rupture of only one membrane - either the chorionic or amniotic membrane, resulting in "pre-PPROM" could precede "classic PPROM" or "high PPROM". The diagnosis of PPROM is classically established by identification of nitrazine positive, fern positive watery leakage from the cervical canal observed during in specula investigation. Other more recent diagnostic tests include the vaginal swab assay for placental alpha macroglobulin-1 test or AFP and IGFBP1. In some rare cases amniocentesis and infusion of indigo carmine has been used to confirm the diagnosis of PPROM. The management of the PPROM requires balancing the potential neonatal benefits from prolongation of the pregnancy with the risk of intra-amniotic infection and its consequences for the mother and infant. Close monitoring for signs of chorioamnionitis (e.g. body temperature, CTG, CRP, leucocytes, IL-6, procalcitonine, amniotic fluid examinations) is necessary to minimize the risk of neonatal and maternal complications. In addition to delayed delivery, broad spectrum antibiotics of penicillin or cephalosporin group and/or macrolide and corticosteroids have been show to improve neonatal outcome [reducing risk of chorioamnionitis (average risk ratio (RR)=0.66), neonatal infections (RR=0.67) and abnormal ultrasound scan of neonatal brain (RR=0.67)]. The positive effect of continuous amnioinfusion through the subcutaneously implanted perinatal port system with amniotic fluid like hypo-osmotic solution in "classic PPROM" less than 28/0 weeks' gestation shows promise but must be proved in future prospective randomized studies. Systemic antibiotics administration in "pre-PPROM" without infection and hospitalization are also of questionable benefit and needs to be further evaluated in well-designed randomized prospective studies to evaluate if it is associated with any neonatal benefit as well as the relationship to possible adverse effect of antibiotics on to fetal development and neurological outcome.

Maternal and neonatal outcomes following expectant management of preterm prelabour rupture of membranes before viability

AIM

To assess the contemporary maternal and neonatal outcomes following expectant management of preterm premature rupture of membranes (PPROM) prior to 24 weeks' gestation and to identify prognostic indicators of this morbid presentation.

METHODS

We performed a systematic review in the Pubmed and EMBASE databases to identify the primary (perinatal mortality, severe neonatal morbidity and serious maternal morbidity) and secondary (neonatal survival and morbidity) outcomes following expectant management of previable PPROM.

RESULTS

Mean latency between PPROM and delivery ranged between 20 and 43 days. Women with PPROM <24 weeks had an overall live birth rate of 63.6% and a survival-to-discharge rate of 44.9%. The common neonatal morbidities were respiratory distress syndrome, bronchopulmonary dysplasia and sepsis. The majority of neonatal deaths within 24 h post birth were associated with pulmonary hypoplasia, severe intraventricular haemorrhage and neonatal sepsis. The common maternal outcomes were chorioamnionitis and caesarean sections. The major predictors of neonatal survival were later gestational age at PPROM, adequate residual amniotic fluid levels, C-reactive protein <1 mg/dL within 24 h of admission and PPROM after invasive procedures.

CONCLUSION

Pregnancy latency and neonatal survival following previable PPROM has improved in recent years, although neonatal morbidity remains unchanged despite recent advances in obstetric and neonatal care. There is heterogeneity in management practices across centres worldwide.

Amnioinfusion for chorioamnionitis

BACKGROUND

Chorioamnionitis is a leading cause of perinatal morbidity and mortality. Amnioinfusion aims at reducing the adverse effects of chorioamnionitis by dilution of the infective organisms or by an anti-microbial effect of the fluid infused.

OBJECTIVES

The objective of this review was to determine the effect of amnioinfusion on clinical and sub-clinical chorioamnionitis, fetal well-being, fetal heart rate characteristics and perinatal and maternal morbidity and mortality.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (6 July 2016), PubMed, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (6 July 2016) and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised clinical trials (RCTs) of amnioinfusion (treatment group) versus no amnioinfusion in women with chorioamnionitis.We would have also considered trials comparing amnioinfusion with sham amnioinfusion; different types or volumes of amnioinfusion fluid but none were identified.Cluster-RCTs and quasi-RCTs were eligible for inclusion but none were identified. We identified one study published in abstract form but it did not contain any numerical data and has therefore been excluded. Studies using a cross-over design are not an appropriate study design and thus were not eligible for inclusion in this review.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed potential studies for inclusion and assessed trial quality. Both review authors independently extracted data and data were checked for accuracy.

MAIN RESULTS

We included one small trial (with data from 34 participants) comparing transcervical amnioinfusion with no amnioinfusion. The trial was considered to be at a high risk of bias overall, due to small numbers, inconsistency in the reporting and lack of information on blinding. Meta-analysis was not possible. Transcervical amnioinfusion was with room temperature saline at 10 mL per minute for 60 minutes, then 3 mL per minute until delivery versus no amnioinfusion. All women received intrauterine pressure catheter, acetaminophen and antibiotics (ampicillin or, if receiving Group B beta streptococcal prophylaxis, penicillin and gentamycin). We did not identify any trials that used transabdominal amnioinfusion.Compared to no amnioinfusion, transcervical amnioinfusion had no clear effect on the incidence of postpartum endometritis (risk ratio (RR) 1.50, 95% confidence interval (CI) 0.29 to 7.87; absolute risk 176/1000 (95% CI 34 to 96) versus 118/1000;low-quality evidence). Nor was there a clear effect in the incidence of neonatal infection (RR 3.00, 95% CI 0.13 to 68.84; absolute risk 0/1000 (95% CI 0 to 0) versus 0/1000; low-quality evidence). The outcome of perinatal death or severe morbidity (such as neonatal encephalopathy, intraventricular haemorrhage, admission to intensive/high care) was not reported in the included trial.In terms of this review's secondary outcomes, the rate of caesarean section was the same in both groups (RR 1.00, 95% CI 0.35 to 2.83; absolute risk 294/1000 (95% CI 103 to 832) versus 294/1000; low-quality evidence). There was no clear difference in the duration of maternal antibiotic treatment between the amnioinfusion and no amnioinfusion control group (mean difference (MD) 16 hours, 95% CI -1.75 to 33.75); nor in the duration of hospitalisation (MD 3.00 hours, 95% CI -15.49 to 21.49). The study did not report any information about how many babies had a low Apgar score at five minutes after birth.Women in the amnioinfusion group had a lower temperature at delivery compared to women in the control group (MD -0.38°C, 95% CI -0.74 to -0.02) but this outcome was not pre-specified in the protocol for this review.The majority of this review's secondary outcomes were not reported in the included study.

AUTHORS' CONCLUSIONS

There is insufficient evidence to fully evaluate the effectiveness of using transcervical amnioinfusion for chorioamnionitis and to assess the safety of this intervention or women's satisfaction. We did not identify any trials that used transabdominal amnioinfusion. The evidence in this review can neither support nor refute the use of transcervical amnioinfusion outside of clinical trials. We included one small study that reported on a limited number of outcomes of interest in this review. The numbers included in this review are too small for meaningful assessment of substantive outcomes, where reported. For those outcomes we assessed using GRADE (postpartum endometritis, neonatal infection, and caesarean section), we downgraded the quality of the evidence to low - with downgrading decisions based on small numbers and a lack of information on blinding. The included study did not report on this review's other primary outcome (perinatal death or severe morbidity).The reduction in pyrexia, though not a pre-specified outcome of this review, may be of relevance in terms of benefits to the fetus of reduced exposure to heat. We postulate that the temperature reduction found may be a direct cooling effect of amnioinfusion with room temperature fluid, rather than reduction of infection. Larger trials are needed to confirm and extend the findings of the trial reviewed here. These should be randomised controlled trials; participants, women with chorioamnionitis; interventions, amnioinfusion; comparisons, no amnioinfusion; outcomes, maternal and perinatal outcomes including neurodevelopmental measures.Further research is justified to determine possible benefits or risks of amnioinfusion for chorioamnionitis, and to investigate possible benefits of reducing temperature in fetuses considered at risk of neurological damage. Research should include randomised trials to examine transcervical or transabdominal amnioinfusion compared with no infusion for chorioamnionitis and examine outcomes listed in the methods of this review.

A new antibiotic regimen treats and prevents intra-amniotic inflammation/infection in patients with preterm PROM

OBJECTIVES

To determine whether a new antibiotic regimen could reduce the frequency of intra-amniotic inflammation/infection in patients with preterm PROM.

STUDY DESIGN

This retrospective cohort study was conducted to evaluate the effect of antibiotics on the frequency of intra-amniotic inflammation/infection based on the results of follow-up transabdominal amniocenteses from 89 patients diagnosed with preterm PROM who underwent serial amniocenteses. From 1993-2003, ampicillin and/or cephalosporins or a combination was used ("regimen 1"). A new regimen (ceftriaxone, clarithromycin and metronidazole) was used from 2003-2012 ("regimen 2"). Amniotic fluid was cultured and matrix metalloproteinase-8 (MMP-8) concentrations were measured.

RESULTS

(1) The rates of intra-amniotic inflammation and intra-amniotic inflammation/infection in patients who received regimen 2 decreased during treatment from 68.8% to 52.1% and from 75% to 54.2%, respectively. In contrast, in patients who received regimen 1, the frequency of intra-amniotic inflammation and infection/inflammation increased during treatment (31.7% to 55% and 34.1% to 58.5%, respectively); and (2) intra-amniotic inflammation/infection was eradicated in 33.3% of patients who received regimen 2, but in none who received regimen 1.

CONCLUSION

The administration of ceftriaxone, clarithromycin and metronidazole was associated with a more successful eradication of intra-amniotic inflammation/infection and prevented secondary intra-amniotic inflammation/infection more frequently than an antibiotic regimen which included ampicillin and/or cephalosporins in patients with preterm PROM.

Preterm prelabor rupture of membranes and outcome of very-low-birth-weight infants in the German Neonatal Network

OBJECTIVE

It was the aim of our study to evaluate the independent effect of preterm prelabor rupture of membranes (PPROM) as a cause of preterm delivery on mortality during primary hospital stay and significant morbidities in very-low-birth-weight (VLBW) infants < 32 weeks of gestation.

DESIGN

Observational, epidemiological study design.

SETTING

Population-based cohort, German Neonatal Network (GNN).

POPULATION

6102 VLBW infants were enrolled in GNN from 2009-2012, n=4120 fulfilled criteria for primary analysis (< 32 gestational weeks, no pre-eclampsia, HELLP (highly elevated liver enzymes and low platelets syndrome) or placental abruption as cause of preterm birth).

METHODS

Multivariable logistic regression analyses included PPROM as potential risk factors for adverse outcomes and well established items such as gestational age in weeks, birth weight, antenatal steroids, center, inborn delivery, multiple birth, gender and being small-for-gestational-age.

RESULTS

PPROM as cause of preterm delivery had no independent effect on the risk of early-onset sepsis, clinical sepsis and blood-culture proven sepsis, while gestational age proved to be the most important contributor to sepsis risk. The diagnosis of PPROM was associated with an increased risk for bronchopulmonary dysplasia (BPD; OR: 1.25, 95% CI: 1.02-1.55, p=0.03) but not with other major outcomes.

CONCLUSIONS

The diagnosis of PPROM per se is not associated with adverse outcome in VLBW infants < 32 weeks apart from a moderately increased risk for BPD. Randomized controlled trials with primary neonatal outcomes are needed to determine which subgroup of VLBW infants benefit from expectant or intentional management of PPROM.