Role of amnioinfusion in the management of premature rupture of the membranes at <26 weeks' gestation

Failed induction of labor and associated factors in Adama Hospital Medical College, Oromia Regional State, Ethiopia

Background:

Failed induction of labor continues to be a public health challenge throughout the world. This failed induction of labor is associated with a higher rate of maternal and fetal morbidity because it increases the unwanted effect of emergency cesarean section. It is also associated with an increased risk of numerous adverse maternal and perinatal outcomes such as uterine rupture, nonreassuring fetal heart rate tracing, postpartum hemorrhage, stillbirth, and severe birth asphyxia. Thus, this study was aimed to assess the failed induction of labor and associated factors in the Adama Hospital Medical College, Oromia Regional State, Ethiopia.

Methods:

A facility-based cross-sectional study was conducted from 1 to 30 December 2020 in Adama Hospital Medical College, Ethiopia. A total of 379 women who underwent labor induction in the Adama Hospital Medical College from December 2019 to November 2020 were enrolled in the study. The participants’ charts were selected using a simple random sampling technique. Data were collected using a pretested and validated structured questionnaire. Descriptive statistics were carried out using frequency tables, proportions, and summary measures. Predictors were assessed using a multivariable logistic regression analysis model and reported using adjusted odds ratio with 95% confidence interval. Statistical significance was considered at a p value <0.05.

Results:

Of 379 induced labor included in the study, the proportion of failed induction was found to be 29.6% (95% confidence interval (25.2, 34.3)). Prelabor rupture of the membrane was found to be the most common indication for induction of labor (46.4%) followed by a hypertensive disorder of pregnancy (21.6%). In the final model of multivariable analysis, predictors such as: nulliparity (adjusted odds ratio = 2.32, 95% confidence interval (1.08, 5.02)), unfavorable cervical status (adjusted odds ratio = 3.46, 95% confidence interval (1.51, 7.94)), prelabor rupture of membrane (adjusted odds ratio = 2.60, 95% confidence interval (1.14, 5.91)), hypertensive disorder of pregnancy (adjusted odds ratio = 3.01;95% confidence interval (1.61, 558)), preinduction membrane status (adjusted odds ratio = 3.63; 95% confidence interval (1.48, 8.86)), and birth weight of greater than 4000 g (adjusted odds ratio = 4.33; 95% confidence interval (1.44, 13.02)) were statistically associated with failed induction of labor.

Conclusion:

The prevalence of failed induction of labor was relatively high in this study area because more than a quarter of mothers who underwent induction of labor had failed induction. This calls for all stakeholders to adhere to locally available induction protocols and guidelines. In addition, pre-induction conditions must be a top priority to improve the outcome of induction of labor.

Continuous amnioinfusion for treatment of mid-trimester preterm premature rupture of membranes with oligoamnios

AIM

Given the scarcity of relevant reports, this study aimed to elucidate whether pregnancy can be prolonged by maintaining the amniotic fluid volume with continuous transabdominal amnioinfusion (TA) for patients with mid-trimester preterm premature rupture of membranes (PPROM) and oligoamnios.

METHODS

We retrospectively examined patients who were managed during hospitalization at our department after developing PPROM between week 22 day 0 and week 25 day 6 of gestation and subsequent oligoamnios (amniotic fluid index [AFI] <5 cm) within 7 days after PPROM onset. Cases between 2006 and 2011 comprised the conventional management group (n = 14); cases administered continuous TA between 2012 and 2017 comprised the continuous TA group (n = 14). The primary outcome was the number of days between PPROM and delivery. The secondary outcomes were the proportion of normal amniotic fluid volume (AFI ≥ 5 cm) maintained between PPROM and delivery and the perinatal prognosis for the mother and infant.

RESULTS

The continuous TA group had significantly more days between PPROM and delivery and a significantly higher proportion of days that a normal amniotic fluid volume was maintained during that period, regardless of antimicrobial agents administered. Although no significant differences in the perinatal prognosis of disease were found between groups, there was a decreasing trend of composite perinatal mortality and morbidity, and the incidence rates were reduced by half.

CONCLUSION

Continuous TA for PPROM with oligoamnios may allow significant prolongation of the gestation period while maintaining the amniotic fluid volume and may lead to improved perinatal prognosis.

Amnioinfusions to Treat Early Onset Anhydramnios Caused by Renal Anomalies: Background and Rationale for the Renal Anhydramnios Fetal Therapy Trial

Anhydramnios caused by early anuria is thought to be universally fatal due to pulmonary hypoplasia. Bilateral renal agenesis and early fetal renal failure leading to anhydramnios constitute early pregnancy renal anhydramnios (EPRA). There have been successful reports of amnioinfusions to promote lung growth in the setting of EPRA. Some of these successfully treated EPRA fetuses have survived the neonatal period, undergone successful dialysis, and subsequently received a kidney transplant. Conversely, there are no reports of untreated EPRA survivors. This early success of amnioinfusions to treat EPRA justifies a rigorous prospective trial. The objective of this study is to provide a review of what is known about fetal therapy for EPRA and describe the Renal Anhydramnios Fetal Therapy trial. We review the epidemiology, pathophysiology, and genetics of EPRA. Furthermore, we have performed systematic review of case reports of treated EPRA. We describe the ethical framework, logistical challenges, and rationale for the current single center (NCT03101891) and planned multicenter trial.

Perinatal outcomes after previable preterm premature rupture of membranes before 24 weeks of gestation

OBJECTIVE

A current descriptive assessment of perinatal outcomes in pregnancies complicated by previable preterm premature rupture of membranes (pPPROM) at <24 weeks of gestation, after expectant treatment.

STUDY DESIGN

Maternal and short-term neonatal data were collected for patients with pPPROM.

RESULTS

Seventy-three patients with 93 fetuses were hospitalized with pPPROM at 15-24 weeks' gestation. Among these patients, 27.4% (n=20) chose pregnancy termination, 27.4% (n=20) miscarried and 45.2% (n=33) proceeded to live births. After a median latency period of 38 days, ranging from 1 to 126 days, 24 singletons and 20 multiples were live-born, of whom 79.5% (n=35) survived the perinatal period. The main neonatal sequelae were pulmonary hypoplasia (29.5%; n=13), connatal infection (56.8%; n=25), intraventricular hemorrhage (25%; n=11; resulting in five neonatal deaths) and Potter's syndrome (15.9%; n=7). Nine newborns died, within an average of 2.8 days (range, 1-10 days). The overall neonatal survival rate was 51.5% - including miscarriages but not elective terminations. The intact survival rate was 45.5% of all live-born neonates.

CONCLUSIONS

Even with limited treatment options, overall neonatal survival is increasing. However, neonatal mortality and morbidity rates remain high. The gestational age at membrane rupture does not predict neonatal outcome.

Long-term neurologic outcomes after common fetal interventions

OBJECTIVE

Fetal interventions have clearly decreased mortality, but the neurological outcomes of survivors are of critical concern. Here we consolidated available data on long-term neurological outcomes after common fetal interventions to guide counseling, management, and future research.

STUDY DESIGN

Published studies assessing long-term neurological outcomes after common fetal interventions from 1990 through 2014 were collected. We included all studies with a cohort of more than 5 patients and with follow-up of 1 year or longer. We divided procedures into those performed for singletons and for multiples. Singleton procedures included amnioinfusion for preterm premature rupture of membranes, intrauterine transfusion for red cell alloimmunization-associated anemia, intrauterine transfusion for parvovirus-associated anemia, vesicoamniotic shunts, thoracoamniotic shunts, ventriculoamniotic shunts, fetal endoscopic tracheal occlusion for congenital diaphragmatic hernia, and open fetal cases by myelomeningocele and others. Multiple procedures included those done for monochorionic twins including serial amnioreduction, selective fetoscopic laser photocoagulation, and selective termination.

RESULTS

Of 1341 studies identified, 28 met the inclusion criteria. We combined available literature for all procedures. Studies varied in their length of follow-up and method of assessing neurological status. Neurological outcome after intervention varied by procedure but was normal in 40-93%, mildly impaired in 3-33%, and severely impaired in 1-40%. Follow-up to school age was rare with the exception of procedures for monochorionic twins.

CONCLUSION

Fetal treatments have been successful in achieving survival in previously hopeless cases, but success should also be determined by the outcomes of survivors. Except for monochorionic twins, there is a dearth of reported long-term outcomes. Standardized reporting of long-term neurological sequelae is imperative so that meaningful analysis and study comparisons can be made.

Severe midtrimester oligohydramnios: treatment strategies

PURPOSE OF REVIEW

Nearly 1% of pregnancies are affected by some type of midtrimester oligohydramnios. Evidence is currently accumulating that suggests the better efficacy of the new therapeutic procedures relative to conventional management. This review summarizes the available evidence.

RECENT FINDINGS

The prolongation of the period between the diagnosis of oligohydramnios and delivery following amnioinfusion and amniopatch techniques appears to be strongly associated with the gestational age and whether the situation was based on rupture of the membranes or not. Case series reveal that amnioinfusion significantly improves the perinatal outcome and prolongs the pregnancy in severe second-trimester oligohydramnios in both idiopathic cases and those involving rupture of the amniotic membranes [preterm prelabor rupture of the membranes (PPROM)]. There is clear evidence of a lower frequency of perinatal complications and successfully prolonged gestation in iatrogenic PPROM after the amniopatch technique relative to population controls.

SUMMARY

Identification of potentially modifiable risk factors for the successful prolongation of pregnancy complicated with midtrimester oligohydramnios, and previable PPROM is needed for the improvement of treatment strategies and prognosis. Randomized trials are needed to determine whether amniotic fluid-replenishing strategies can improve pregnancy outcomes.

Amnioinfusion in very early preterm prelabor rupture of membranes (AMIPROM): pregnancy, neonatal and maternal outcomes in a randomized controlled pilot study

OBJECTIVE

To assess short- and long-term outcomes of pregnant women with very early rupture of membranes randomized to serial amnioinfusion or expectant management, and to collect data to inform a larger, more definitive clinical trial.

METHODS

This was a prospective non-blinded randomized controlled trial with randomization stratified for pregnancies in which the membranes ruptured between 16 + 0 and 19 + 6 weeks' gestation and 20 + 0 and 23 + 6 weeks' gestation to minimize the risk of random imbalance in gestational age distribution between randomized groups. Intention-to-treat analysis was used. The study was conducted in four UK hospital-based fetal medicine units (Liverpool Women's NHS Trust, St Mary's Hospital Manchester, Birmingham Women's NHS Foundation Trust and Wirral University Hospitals Trust). The participants were women with confirmed preterm prelabor rupture of membranes at 16 + 0 to 24 + 0 weeks' gestation. Women with multiple pregnancy, fetal abnormality or obstetric indication for immediate delivery were excluded. Participants were randomly allocated to either serial weekly transabdominal amnioinfusions if the deepest pool of amniotic fluid was < 2 cm or expectant management until 37 weeks' gestation. Short-term maternal, pregnancy and neonatal and long-term outcomes for the child were studied. Long-term respiratory morbidity was assessed using validated respiratory questionnaires at 6, 12 and 18 months of age and infant lung function test at around 12 months of age. Neurodevelopment was assessed using the Bayley Scales of Infant Development, second edition (BSID-II) at corrected age of 2 years.

RESULTS

Fifty-eight women were randomized to the study. Two babies were excluded from the analysis because of termination of pregnancy for lethal anomaly, leaving 56 participants (28 assigned to serial amnioinfusion and 28 to expectant management) recruited between 2002 and 2009. There was no significant difference in perinatal mortality (19/28 vs 19/28; relative risk (RR) 1.0 (95% CI, 0.70-1.43)) and maternal or neonatal morbidity. The overall chance of surviving without long-term respiratory or neurodevelopmental disability was 4/56 (7.1%); 4/28 (14.3%) in the amnioinfusion group and 0/28 in the expectant group (RR 9.0 (95% CI, 0.51-159.70)).

CONCLUSIONS

This pilot study found no major differences in maternal, perinatal or pregnancy outcomes. The study was not designed to show a difference between the groups and the number of survivors was too small to draw any conclusions about long-term outcomes. It does, however, signal that a larger definitive study to evaluate amnioinfusion for improvement in healthy survival is needed. The pilot suggests that, with appropriate funding, such a study is feasible.

Amnioinfusion for third trimester preterm premature rupture of membranes

BACKGROUND

Preterm premature rupture of membranes (PPROM) is a leading cause of perinatal morbidity and mortality. Amnioinfusion aims to restore amniotic fluid volume by infusing a solution into the uterine cavity.

OBJECTIVES

The objective of this review was to assess the effects of amnioinfusion for PPROM on perinatal and maternal morbidity and mortality.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (2 December 2013).

SELECTION CRITERIA

Randomised trials of amnioinfusion compared with no amnioinfusion in women with PPROM.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed trials for inclusion. Two review authors independently assessed trial quality and extracted data. Data were checked for accuracy.

MAIN RESULTS

We included five trials, of moderate quality, but we only analysed data from four studies (with a total of 241 participants). One trial did not contribute any data to the review.Transcervical amnioinfusion improved fetal umbilical artery pH at delivery (mean difference 0.11; 95% confidence interval (CI) 0.08 to 0.14; one trial, 61 participants) and reduced persistent variable decelerations during labour (risk ratio (RR) 0.52; 95% CI 0.30 to 0.91; one trial, 86 participants).Transabdominal amnioinfusion was associated with a reduction in neonatal death (RR 0.30; 95% CI 0.14 to 0.66; two trials, 94 participants), neonatal sepsis (RR 0.26; 95% CI 0.11 to 0.61; one trial, 60 participants), pulmonary hypoplasia (RR 0.22; 95% CI 0.06 to 0.88; one trial, 34 participants) and puerperal sepsis (RR 0.20; 95% CI 0.05 to 0.84; one trial, 60 participants). Women in the amnioinfusion group were also less likely to deliver within seven days of membrane rupture (RR 0.18; 95% CI 0.05 to 0.70; one trial, 34 participants). These results should be treated with circumspection as the positive findings were mainly due to one trial with unclear allocation concealment.

AUTHORS' CONCLUSIONS

These results are encouraging but are limited by the sparse data and unclear methodological robustness, therefore further evidence is required before amnioinfusion for PPROM can be recommended for routine clinical practice.

Prenatal incarceration of caput succedaneum: A case report

Caput succedaneum is relatively common at birth but infrequently diagnosed in utero. We report the first case of a prenatal incarcerated caput succedaneum after cervical cerclage in a patient with premature rupture of the membranes (PPROM). A 41-year-old woman was referred and admitted to our hospital due to PPROM at 19 wk of gestation. Aggressive therapy, including amnioinfusion, cervical cerclage, and administration of antibiotics and tocolysis, was initiated. At 24 wk of gestation, a thumb tip-sized and polyp-like mass, which was irreducible, was delineated with a vaginal examination, vaginal speculum, and transvaginal ultrasonography, leading to the diagnosis of incarcerated caput succedaneum. Under general anesthesia, the incarcerated caput succedaneum was repositioned with fingers after cutting the string to avoid necrosis, and then, placement of a McDonald cervical cerclage was undertaken again. At 26 wk of gestation, she delivered a 678 g girl through an emergency cesarean section performed due to profuse bleeding and prolonged decelerations. A slight bulge with hair was observed on the head by palpation at birth. Cephalic ultrasonography, X-ray, magnetic resonance imaging and electroencephalogram confirmed no abnormality. Although the baby needed oxygen (0.2 L/min) at the time of hospital discharge, she has grown favorably at three years of corrected age.

Amniopatch procedure after previable iatrogenic rupture of the membranes: a two-center review

OBJECTIVE

This study aimed to analyze success rates and pregnancy outcomes of amniopatch procedures for previable iatrogenic preterm prelabour rupture of the membranes (PPROM) with associated oligohydramnios.

METHODS

Retrospective analysis of amniopatch procedures performed at the University Hospitals Leuven, Belgium, and the Mount Sinai Hospital Toronto, Canada. Cases were analyzed overall and in two sub-groups: PPROM after a needle-based procedure (NP group, n = 13) or after fetoscopic intervention (FI group, n = 11). Complete technical success was defined as cessation of leakage and normalization of amniotic fluid volume, partial success as cessation of leakage, or re-establishment of volume. Further outcomes were pregnancy duration and outcome, fetal/neonatal morbidity and mortality, and maternal morbidity.

RESULTS

Gestational age at amniopatch was comparable in both groups (NP: 20.1, FI: 21.0 weeks). Amniopatch was completely and partially successful in 29% (NP: 31%; FI: 27%) and 29% (NP: 15%; FI: 45%), respectively. Mean gestational age at delivery was 27.5 weeks (NP: 25.5; FI: 29.4 weeks). Overall neonatal survival was 17/31 (55%) (NP: 4/13 (31%), FI: 13/18 (72%); p = .02). Chorioamnionitis occurred in three cases, two associated with maternal sepsis. Severe neonatal morbidity occurred in two survivors.

CONCLUSION

Amniopatch for iPPROM was successful in 58%, with an overall live birth rate of 68% and survival to discharge of 55%.

Transabdominal amnioinfusion for preterm premature rupture of membranes: a systematic review and metaanalysis of randomized and observational studies

OBJECTIVE

The purpose of this study was to review systematically the efficacy of transabdominal amnioinfusion (TA) in early preterm premature rupture of membranes (PPROM).

STUDY DESIGN

We conducted a literature search of EMBASE, MEDLINE, and ClinicalTrials.gov databases and identified studies in which TA was used in cases of proven PPROM and oligohydramnios. Risk of bias was assessed for observational studies and randomized controlled trials. Primary outcomes were latency period and perinatal mortality rates.

RESULTS

Four observational studies (n = 147) and 3 randomized controlled trials (n = 165) were eligible. Pooled latency period was 14.4 (range, 8.2-20.6) and 11.41 (range -3.4 to 26.2) days longer in the TA group in the observational and the randomized controlled trials, respectively. Perinatal mortality rates were reduced among the treatment groups in both the observational studies (odds ratio, 0.12; 95% confidence interval, 0.02-0.61) and the randomized controlled trials (odds ratio, 0.33; 95% confidence interval, 0.10-1.12).

CONCLUSION

Serial TA for early PPROM may improve early PPROM-associated morbidity and mortality rates. Additional adequately powered randomized control trials are needed.

Amnioinfusion for preterm premature rupture of membranes

BACKGROUND

Preterm premature rupture of membranes (PPROM) is a leading cause of perinatal morbidity and mortality. Amnioinfusion aims to restore amniotic fluid volume by infusing a solution into the uterine cavity.

OBJECTIVES

The objective of this review was to assess the effects of amnioinfusion for PPROM on perinatal and maternal morbidity and mortality.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 September 2011).

SELECTION CRITERIA

Randomised trials of amnioinfusion compared to no amnioinfusion in women with PPROM.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed trials for inclusion. Two review authors independently assessed trial quality and extracted data. Data were checked for accuracy.

MAIN RESULTS

We included five trials but we only analysed data from four studies (with a total of 241 participants). One trial did not contribute any data to the review.Transcervical amnioinfusion improved fetal umbilical artery pH at delivery (mean difference 0.11; 95% confidence interval (CI) 0.08 to 0.14; one trial, 61 participants) and reduced persistent variable decelerations during labour (risk ratio (RR) 0.52; 95% CI 0.30 to 0.91; one trial, 86 participants).Transabdominal amnioinfusion was associated with a reduction in neonatal death (RR 0.30; 95% CI 0.14 to 0.66; two trials, 94 participants), neonatal sepsis (RR 0.26, 95% CI 0.11 to 0.61; one trial, 60 participants), pulmonary hypoplasia (RR 0.22; 95% CI 0.06 to 0.88; one trial, 34 participants) and puerperal sepsis (RR 0.20; 95% CI 0.05 to 0.84; one trial, 60 participants). Women in the amnioinfusion group were also less likely to deliver within seven days of membrane rupture (RR 0.18; 95% CI 0.05 to 0.70; one trial, 34 participants). These results should be treated with circumspection as the positive findings were mainly due to one trial with unclear allocation concealment.

AUTHORS' CONCLUSIONS

These results are encouraging but are limited by the sparse data and unclear methodological robustness, therefore further evidence is required before amnioinfusion for PPROM can be recommended for routine clinical practice.

Management of oligohydramnios in pregnancy

The finding of oligohydramnios in pregnancy is problematic. The various mechanisms that control amniotic fluid, the inability to precisely measure and quantify the amount, and the relevance of a "decreased" amount of fluid make the management of this finding unclear. Given the limited amount of data, the single deepest vertical pocket may be a better method than the amniotic fluid index to define oligohydramnios. A large prospective study is needed to develop the most optimal management recommendations, especially for idiopathic oligohydramnios at or near term.

Management of premature prelabor rupture of the membranes

Premature prelabor rupture of the fetal membranes affects about 3% of pregnancies. The cause is usually infection, especially at earlier gestations. The prognosis and the risks of delivery are both much worse at earlier gestations. Before viable pregnancy, termination may be offered. Once the fetus is viable, steroids to mature the fetal lungs and antibiotics to reduce infection are the mainstays of treatment. Delivery is recommended in the presence of signs of clear-cut infection at early gestational ages. At later ones, balancing the risks of infection from conservative treatment against the risk of prematurity from delivery is difficult. Published trials to date have not given clear guidance, but a number are ongoing.

Transabdominal amnioinfusion in preterm premature rupture of membranes

OBJECTIVE

To evaluate the effect of transabdominal amnioinfusion on prolongation of pregnancy, and maternal and neonatal outcomes in preterm premature rupture of membranes (pPROM).

METHODS

We conducted a prospective randomized controlled study of women with pPROM during singleton live pregnancy-between 26 and 33+6weeks-whose amniotic fluid index (AFI) was less than the 5th percentile. The study group underwent transabdominal amnioinfusion at admission and then weekly if their AFI fell below the 5th percentile again. The control group received expectant management.

RESULTS

The difference in the mean interval from pPROM to delivery between the groups was not statistically significant. Neonatal and maternal outcomes were significantly improved in the study group compared with the control group (fetal distress [10% vs 37%]; early neonatal sepsis [17% vs 63%]; neonatal mortality [17% vs 63%]; spontaneous delivery [83% vs 53%]; and postpartum sepsis [7% vs 33%]).

CONCLUSION

Transabdominal amnioinfusion reduced fetal distress, early neonatal sepsis, and neonatal mortality. In the study group, more participants delivered spontaneously and there were fewer cases of postpartum sepsis, although the pPROM-delivery interval was not increased.

Prenatal factors in the development of chronic lung disease

Chronic lung disease (CLD), defined as chronic oxygen dependency, is a common outcome of neonatal intensive care. It occurs most frequently in infants born very prematurely, but also in infants born at term who had severe lung disease and those with abnormal antenatal lung growth due particularly to reduction in fetal breathing movements, amniotic fluid volume or intrathoracic space. There are, however, other causes and the importance of antenatal infection/inflammation regarding impairment of antenatal lung growth is increasingly recognised. Affected infants can suffer chronic respiratory morbidity including an excess of respiratory symptoms and lung function abnormalities even in adulthood. Antenatal interventions directed at improving lung growth are available, but require testing inappropriately designed trials with pulmonary function at follow-up as an outcome.

Gestational age at glucocorticoids administration after premature rupture of membranes and cerebral white matter damage

OBJECTIVE

We investigated whether gestational age at glucocorticoids administration in very preterm premature rupture of membranes (PROM) affects the occurrence of neonatal cerebral white matter damage (WMD).

METHODS

In a cohort of singleton neonates born at 24.0-33.6 weeks after PROM who underwent at least one full course of glucocorticoids (n = 130), we compared the gestational age at first and last course of glucocorticoids between those who developed WMD (n = 8) and those who did not (n = 122) after adjusting for gestational age at PROM using logistic regression with P < 0.05 considered significant.

RESULTS

Gestational age at first course of glucocorticoids (P = 0.2), at last course of glucocorticoids (P = 0.2) and at delivery (P = 0.2), were not significantly different between those who developed WMD and those who did not. Although latency between PROM and first course of glucocorticoids was protective against WMD (P = 0.02), the significance was lost after controlling for gestational age at PROM, which was significantly lower in cases that developed WMD (P < 0.01).

CONCLUSIONS

In very preterm PROM, the beneficial effect of glucocorticoids on occurrence of WMD is not related to gestational age at steroid administration.

Amniotic fluid abnormalities

The complex nature of amniotic fluid reflects contributions from many fetal systems, many functional roles, and multiple interactions with fetal maturation, obstetric, and maternal factors. Simple ultrasound measurement, probably done best with the maximum vertical pocket method, has a clinical role in fetal surveillance, substantiated by extensive level II and some level I evidence. Interventions (amnioinfusion for oligohydramnios, amnioreduction for polyhydramnios) have not been studied effectively in controlled fashion, with the exception of intrapartum applications, where effective reduction of cesarean delivery for fetal distress and perinatal impacts of meconium aspiration may follow amnioinfusion. A wealth of research opportunities exists into regulation of amniotic fluid constituents and their relation to preterm delivery.

Treatment with amniopatch of premature rupture of membranes after first-trimester chorionic villus sampling

OBJECTIVE

To assess the amniopatch procedure when premature rupture of membranes occurs after first-trimester chorionic villus sampling (CVS).

STUDY DESIGN

From May 2001 to June 2004, the amniopatch procedure was offered in cases of premature rupture of membranes after CVS when severe oligohydramnios was present (largest vertical pocket < 2 cm) and persistent (more than 1 week).

RESULTS

The amniopatch was placed in five pregnancies at 12-18 weeks of gestation, resulting in amniotic fluid restoration in all but one pregnancy. In three pregnancies, fetal demise was observed at 1, 2 and 36 days after the procedure. The last procedure resulted in a healthy newborn.

CONCLUSION

Although the amniopatch restored normal amniotic fluid levels in all cases, 4 of the 5 cases resulted in fetal demise.

The experience of amnioinfusion for oligohydramnios during the early second trimester

OBJECTIVE

In the past, oligohydramnios occurring early during the secondary trimester was the reason to terminate the pregnancy because of poor prognosis. Even though amnioinfusion has been reported for improving the prognosis of the infant, it is still not frequently used because of unfavorable results. We present our experience with amnioinfusion for oligohydramnios with or without preterm premature rupture of membranes.

MATERIALS AND METHODS

A retrospective study was performed from July 2005 to December 2006 in our hospital. Amnioinfusions were performed in pregnant women found with oligohydramnios during their second trimesters. Chromosomal studies were recommended and performed under informed consent. Level II sonography was performed after each amnioinfusion. Magnetic resonance imaging was arranged for those with suggested urinary tract malformations.

RESULTS

Seventeen cases were included in our study. No mother was exposed to drugs that have been associated with oligohydramnios. The women received one to six procedures of amnioinfusion separately with a total of 28 procedures. Only one procedure failed. No chromosomal anomalies were found. Fetal anomalies were found after amnioinfusion in five cases. One woman had preterm delivery within 1 week after amnioinfusion. In the four cases of oligohydramnios with rupture of membranes, one case had a healthy full-term baby delivered. In the 13 cases of oligohydramnios without rupture of membranes, there were two preterm infants delivered before 34 weeks of gestation, including pulmonary hypoplasia in one neonate, and three healthy babies delivered after 35 weeks of gestation.

CONCLUSION

Amnioinfusion performed the first time might provide some benefits for those with early-onset oligohydramnios, such as to provide confirmation of rupture of membranes, detailed sonography examination and further counseling. We would recommend that this procedure be considered once for these cases.

Predictors of perinatal survival in a cohort of pregnancies with severe oligohydramnios due to premature rupture of membranes at <26 weeks managed with serial amnioinfusions

OBJECTIVE

To evaluate whether successful amnioinfusion is an independent predictor of perinatal survival in a cohort of cases with extreme and persistent oligohydramnios due to preterm premature rupture of membranes (pPROM) who reached viability and were managed with serial amnioinfusions.

STUDY DESIGN

We included all consecutive singleton pregnancies with pPROM at <26 weeks and oligohydramnios lasting >4 days between 1/1991 and 12/2001 and who consented to undergo amnioinfusion (n=77). Women received serial transabdominal amnioinfusions in an attempt to maintain a pocket of fluid >2 cm. The procedure was deemed successful if the median deepest pocket of fluid during the latency period was >2 cm. Excluded were miscarriages (n=10), fetal deaths before viability (24 weeks) (n=15), and cases that did not develop oligohydramnios (n=17). Prenatal predictors of outcome were compared between cases who survived the perinatal period and those who did not using Wilcoxon rank-sum test, Fisher's exact test and stepwise logistic regression analysis, with a two-tailed P<0.05 considered significant.

RESULTS

Of the 35 patients fulfilling the study criteria, 20 (57%) survived the perinatal period. Perinatal survivors had similar gestational age at pPROM (P=0.68) and at first amnioinfusion (P=0.53) as those who died in the perinatal period, but longer latency (P=0.013). Consequently, median gestational age at delivery [29.2 (25.4-35.3) weeks versus 26.1 (24.0-34.0) weeks, P<0.001] and median birth weight [1220 (650-2240) g versus 863 (520-2200) g, P=0.001] were significantly greater among survivors than among those who died. Significant predictors of survival at univariate analysis were entered into a stepwise logistic regression analysis in the chronological order in which they normally occur. The analysis demonstrated that successful amnioinfusion (OR=6.9, 95% CI 1.2-40.4) and administration of steroids (OR=14.6, 95% CI 1.5-144.1) were independent and significant predictors of perinatal survival.

CONCLUSION

In a cohort of women with pPROM at <26 weeks and severe oligohydramnios managed with serial amnioinfusions, successful procedures and prenatal administration of corticosteroids are the only independent predictors of perinatal survival.

Risk factors for previable premature rupture of membranes or advanced cervical dilation: a case control study

OBJECTIVE

The purpose of this study was to identify risk factors for second trimester premature preterm rupture of membranes or advanced cervical dilation in a high-risk population.

STUDY DESIGN

A retrospective case control study was performed that compared women with premature preterm rupture of membranes or advanced cervical dilation to term control subjects. The cases included all singleton pregnancies between 14 and 24 weeks of gestation with premature preterm rupture of membranes or advanced cervical dilation between 1996 and 2000. The next 2 term deliveries were chosen as control subjects. The variables compared between cases and control subjects included pregnancy history, infectious and medical histories, cervical/uterine procedures, and habits. This study had institutional review board approval.

RESULTS

There were 102 women with premature preterm rupture of membranes, 56 women with advanced cervical dilation, and 316 control subjects. The mean gestational ages for premature preterm rupture of membranes or advanced cervical dilation were 20 +/- 2.6 and 19.9 +/- 2.6 weeks. Tobacco use, history of or current cervical incompetence, previous second trimester delivery, previous termination at <20 weeks of gestation, and previous premature preterm rupture of membranes were associated significantly with premature preterm rupture of membranes or advanced cervical dilation compared with term control subjects. When controlled for parity, age, marital status, and race, these variables remained significant. Bacterial vaginosis in current pregnancy was associated significantly with only advanced cervical dilation but not premature preterm rupture of membranes compared with control subjects. A history of Chlamydia was most common in the term control subjects (19.6%).

CONCLUSION

In a high-risk population of inner city women, only pregnancy history and tobacco use distinguished women with second trimester premature preterm rupture of membranes or advanced cervical dilation from term control subjects. No infectious risk factors distinguished control women from women with premature preterm rupture of membranes. The only modifiable risk identified was tobacco use.

Gestational age at preterm premature rupture of membranes: a risk factor for neonatal white matter damage

OBJECTIVE

Gestational age at delivery and spontaneous prematurity are independent risk factors for white matter damage (WMD). However, among infants delivered spontaneously after preterm premature rupture of membranes (PPROM), latency of PPROM has been inconsistently correlated with risk of WMD. We have explored whether gestational age at membrane rupture is independently associated with WMD.

STUDY DESIGN

Using a cohort of 196 liveborn singleton nonanomalous neonates born at 24.0 to 33.6 weeks from January 1993 to December 2002 after pPROM and who survived 7 days, we compared the characteristics of those who developed WMD (n = 15) with those who did not (n = 181) using Fisher exact test, Student t test, and logistic regression analysis, with a 2-tailed P < .05 or odds ratio (OR) with 95% CI not inclusive of the unity considered significant.

RESULTS

Stepwise logistic regression analysis demonstrated that gestational age at PPROM (P < .001, OR 0.79) was significantly associated with WMD. The association was independent of corticosteroid administration (P = .016), latency interval (P = .69), gestational age at delivery (P = .99), and birth weight (P = .62).

CONCLUSION

Among premature infants born at <34 weeks after pPROM, gestational age at diagnosis is independently associated with WMD.

Transabdominal amnioinfusion in preterm premature rupture of membranes: a randomised controlled trial

OBJECTIVE

To evaluate the role of transabdominal amnioinfusion in improving the perinatal outcomes of pregnancies complicated by preterm premature rupture of membranes (pPROM).

DESIGN

A randomised controlled trial.

SETTING

A teaching hospital in Italy, obstetric unit. Population Women with singleton pregnancies complicated by pPROM, between 24 + 0 and 32 + 6 weeks of gestation.

METHODS

Patients were randomised 24 hours after admission to our referral hospital, to expectant management with transabdominal amnioinfusion or expectant management only.

MAIN OUTCOME MEASURES

The effects of transabdominal amnioinfusion on pPROM-delivery interval and on perinatal outcomes.

RESULTS

Of the 65 women with pPROM 34 met the inclusion criteria. Seventeen women were assigned to amnioinfusion (the amnioinfusion group) and the other 17 to expectant management. Compared with the control group (median: 8 days; range: 3-14), the pPROM-delivery period was significantly longer in women who underwent amnioinfusion (median: 21 days; range: 15-29) (P < 0.05). Women with amnioinfusion were less likely to deliver within seven days since pPROM (RR: 0.18; range: 0.04-0.69 95% CI) or within two weeks (RR: 0.46; range: 0.21-1.02 95% CI). In the amnioinfusion group the neonatal survival was significantly higher at each gestational age (P < 0.01, Yates's correction for Log Rank Test) with a reduction in pulmonary hypoplasia.

CONCLUSIONS

We demonstrated that compared with standard expectant management the treatment with transabdominal amnioinfusion after pPROM resulted in significant prolongation of pregnancy and better neonatal outcomes.

The Use of Ultrasound Measurement of Fetal Lung Length to Predict Neonatal Respiratory Outcome after Prolonged Premature Rupture of the Membranes

OBJECTIVE

The purpose of this study was to investigate the use of fetal lung length estimation by ultrasound in the prediction of adverse neonatal respiratory outcome after prolonged preterm rupture of the membranes.

METHODS

From the hospital database of all cases of spontaneous membrane rupture </=28 weeks' gestation, normal singleton pregnancies with membrane rupture for at least 7 days and delivery after 24 weeks' gestation where lung length measurements were available were studied. The study period was 5 years. At least one lung length measurement >/=7 days after membrane rupture needed to be available and the last lung length prior to delivery was used to predict adverse respiratory outcome. Complete neonatal follow-up was available on all babies. Neonatal outcome measures included survival, bronchopulmonary dysplasia defined as an oxygen requirement at 36 weeks' gestation, and neonatal respiratory death in non-survivors. Two groups, good and poor outcomes, were defined. A comparison of the last lung length before delivery (corrected for gestation) between the good and poor outcome groups was made to determine whether lung length could predict neonatal outcome.

RESULTS

There were 43 live births. All had received antenatal corticosteroids as part of the management of prematurity. There were no differences in maternal age, ethnicity, parity and the incidence of antepartum haemorrhage between the good and poor outcome groups. Parameters significantly associated with good outcome included gestation at membrane rupture, large pool of amniotic fluid and gestation at delivery. The last fetal lung length did not predict adverse neonatal respiratory outcome. In the 28 babies where membrane rupture was >/=21 days the findings were the same.

CONCLUSION

Fetal lung length determined by antenatal ultrasound does not predict adverse neonatal respiratory outcome and the prediction of pulmonary hypoplasia in live borns after prolonged preterm rupture of the membranes remains an elusive goal.

Is There Significant Improvement in Neonatal Outcome after Treating pPROM Mothers with Amnio-Infusion?

The aim of this study was to determine the effects of amnio-infusion treatment on fetal and neonatal mortality and neonatal pulmonary development in women with singleton pregnancies and premature rupture of the membranes occurring at a gestational age of <26 weeks and who had severe oligohydramnios. The treated group of 45 consenting women received serial amnio-infusion and was compared with the control group of 44 women who underwent waiting treatment. Our study confirmed a higher number of live births in the treated group, especially in cases with a gestational age at rupture (GAR) of <20 weeks. Furthermore, even if GAR is an important factor for predicting pulmonary hypoplasia, amnio-infusion treatment reduces the probability of pulmonary hypoplasia. In fact, over 20 weeks, amnio-infusion treatment significantly reduces the risk of pulmonary hypoplasia even if normal lung development cannot be guaranteed.

Successful patching of iatrogenic rupture of the fetal membranes

Rupture of the fetal membranes is a common, but potentially serious complication of invasive fetal procedures. Quintero described a technique to seal the fetal membrane defect by means of a bloodpatch, usually called 'amniopatch' in this application. The successful use in two consecutive patients with ruptured membranes after a fetoscopic intervention at respectively 17 and 22 weeks' gestational age is described, together with a literature review of published experience.

Transabdominal amnioinfusion treatment of severe oligohydramnios in preterm premature rupture of membranes at less than 26 gestational weeks

OBJECTIVE

To evaluate the efficacy of transabdominal amnioinfusion on feto-neonatal and maternal morbidity and feto-neonatal mortality.

METHODS

We studied 71 patients with preterm premature rupture of membranes (pPROM) at <26 weeks of gestational age. Thirty-four patients were managed expectantly and 37 underwent serial transabdominal amnioinfusion with saline every 7 days in case of persistent oligohydramnios.

RESULTS

Latency period pPROM delivery, week of delivery (26.0 vs. 22.4, p<0.001), neonatal weight (922 vs. 602, p<0.01) and the percentage of intrauterine fetal survival were higher in treated than in control groups (64.8 vs. 32.3%, p<0.01). In amnioinfusion-treated patients, we did not note a higher rate of complications from infection during both pregnancy and puerperium. In the amnioinfusion group, fluid loss within 6 h after infusion is the main variable in predicting pulmonary hypoplasia and neonatal survival.

CONCLUSIONS

Our data suggest that amnioinfusion seems to be a low fetal and maternal risk technique that modifies the natural history of pPROM, improving fetal intrauterine stay and survival.

Sacrococcygeal teratoma: prenatal assessment, fetal intervention, and outcome

PURPOSE

To understand the natural history and define indications for fetal intervention in sacrococcygeal teratoma (SCT), the authors reviewed all cases of fetal SCT presenting for evaluation.

METHODS

Prenatal diagnostic studies including ultrasound scan, magnetic resonance imaging (MRI), echocardiography and pre- and postnatal outcomes were reviewed in 30 cases of SCT that presented between September 1995 and January 2003.

RESULTS

The mean gestational age (GA) at presentation was 23.9 weeks (range, 19 to 38.5) with 3 sets of twins (10%). Overall outcomes included 4 terminations, 5 fetal demises, 7 neonatal deaths, and 14 survivors. Significant obstetric complications occurred in 81% of the 26 continuing pregnancies: polyhydramnios (n = 7), oligohydramnios (n = 4), preterm labor (n = 13), preeclampsia (n = 4), gestational diabetes (n = 1), HELLP syndrome (n = 1), and hyperemesis (n = 1). Fetal intervention included cyst aspiration (n = 6), amnioreduction (n = 3), amnioinfusion (n = 1), and open fetal surgical resection (n = 4). Indications for cyst aspiration and amnioreduction were maternal discomfort, preterm labor, and prevention of tumor rupture at delivery. Although 15 SCTs were solid causing risk for cardiac failure, only 4 fetuses met criteria for fetal debulking based on ultrasonographic and echocardiographic evidence of impending high output failure and favorable anatomy at 21, 23.6, 25, and 26 weeks' gestation. Intraoperative events included maternal blood transfusion (n = 1), fetal blood transfusion (n = 2), chorioamniotic membrane separation (n = 2), and fetal arrest requiring successful cardiopulmonary resuscitation (CPR) (n = 1). In the fetal resection group, 3 of 4 survived with mean GA at delivery of 29 weeks (range, 27.6 to 31.7 weeks), mean birth weight of 1.3 kg, hospital stay ranging from 16 to 34 weeks, and follow-up ranging from 20 months to 6 years. Postnatal complications in the fetal surgery group included neonatal death (n = 1, secondary to premature closure of ductus arteriosus with cardiac failure), embolic event (n = 1, resulting in unilateral renal agenesis, jejunal atresia), chronic lung disease (n = 1), and tumor recurrence (n = 1).

CONCLUSIONS

For fetal SCT, the rapidity at which cardiac compromise can develop and the high incidence of obstetric complications warrant close prenatal surveillance. Amnioreduction, cyst aspiration, and surgical debulking are potentially life-saving interventions.

Transabdominal antepartum amnioinfusion

OBJECTIVES

The purpose of our study was to evaluate whether transabdominal antepartum amnioinfusion is associated with maternal complications during pregnancy and at childbirth.

METHODS

Fifty-three pregnant women, hospitalized for oligohydramnios and submitted to transabdominal antepartum amnioinfusion between 16 and 34 weeks' gestational age, were compared with a historic group of 42 pregnant women treated conservatively.

RESULTS

The study population was divided into two groups of women with ruptured and unruptured membranes (Groups A and B, respectively). The latency period between time of admission and term of pregnancy was more favorable in amnioinfused patients (Group A: 22 vs. 11 days; Group B: 30 vs. 9 days), and none of the maternal adverse events under study was significantly more common in amnioinfused patients. By contrast, maternal temperature over 38 degrees C was more frequent among controls than among amnioinfused patients with ruptured membranes (23% vs. 4%); so was the number of cesarean sections for fetal distress in Group B (50 vs. 11%).

CONCLUSIONS

Antepartum amnioinfusion does not appear to induce greater complications than conservative treatment for oligohydramnios, with or without premature rupture of membranes. On the contrary, this procedure seems to offer several benefits to pregnant women.

Test amnioinfusion to determine suitability for serial therapeutic amnioinfusion in midtrimester premature rupture of membranes

OBJECTIVE

To evaluate whether a test amnioinfusion procedure is useful in selecting cases of midtrimester preterm premature rupture of membranes (PPROM) which may benefit from serial amnioinfusions if the initial fluid is retained.

STUDY DESIGN

The Centre for Fetal Care database between 1992 and 2000 was reviewed for women with PPROM <26 weeks who had undergone amnioinfusion. Amniotic fluid index (AFI) was assessed before and after a test amnioinfusion procedure. Those who retained fluid > or =48 h underwent serial AFI assessment with a view to serial amnioinfusion when oligohydramnios recurred.

RESULTS

Eighty-five amnioinfusion procedures were performed in 60 women with oligohydramnios. Nineteen of these women presented with confirmed PPROM at a median gestation of 19 (range 15-22) weeks and severe olighohydramnios (median AFI 1, range 0-3 cm), in whom 20 test amnioinfusions were carried out. Two amnioinfusions were abandoned during the procedure because of fetal bradycardia and both mothers opted for termination of pregnancy. Only 4 women retained fluid during the test amnioinfusion, 1 of whom miscarried at 19 weeks before serial amnioinfusion could be started. The remaining 3 underwent a median of 4 (range 1-6) serial amnioinfusion procedures; none had evidence of pulmonary hypoplasia. Thirteen (68%) leaked fluid within 48 h; within this group there was 1 subsequent miscarriage and 9 pregnancy terminations. The remaining 3 pregnancies resulted in livebirths 2 of which had pulmonary hypoplasia with 1 early neonatal death. Overall survival was poor (4/19), largely attributed to the high incidence of terminations in the presence of persistent severe oligohydramnios. In continuing pregnancies reaching viability survival was 67% (4 of 6).

CONCLUSION

Three quarters of women with mid-trimester PPROM lose fluid at test amnioinfusion and therefore would not be suitable candidates for serial amnioinfusion. However, if infused fluid is retained, this allows subsequent serial amnioinfusion and prolongation of pregnancy in about 75%, with an attendant decrease in the risk of pulmonary hypoplasia. However, even successful serial amnioinfusion remains associated with procedure-related complications (i.e. chorioamnionitis, placental abruption) which themselves may predispose to preterm delivery.

Survival in second trimester oligohydramnios secondary to bilateral pelviureteral junction obstruction

The extent and onset of obstruction in hydronephrosis determine the varying degrees of renal impairment. Bilateral hydronephrosis, especially in combination with oligohydramnios, is considered a negative predictor for pregnancy outcome. We describe a case of bilateral pelviureteral junction obstruction causing severe oligohydramnios between 25 and 29 weeks of gestation. The prenatal and postnatal findings and treatment are demonstrated. In the presence of bilateral renal impairment and oligohydramnios, our patient had an unfavorable prognosis. The respiratory and renal function, however, were better than expected. We show how urinary tract reconstruction and neonatal intensive therapy can result in an acceptable outcome.

An aggressive interventional protocol for early midtrimester premature rupture of the membranes using gelatin sponge for cervical plugging

OBJECTIVE

This study was performed to evaluate a protocol for treatment of previable premature rupture of membranes (PROM) that includes the administration of gelatin sponge to retard the loss of fluid from the amniotic cavity.

STUDY DESIGN

Women with PROM at <or=21 weeks' gestation with a structurally normal singleton; having no evidence of infection, active bleeding, or labor; and a maximum vertical fluid pocket of less than 1.5 cm were candidates. Interventions included hospital admission, amnioinfusion, cervical cerclage, administration of gelatin sponge (Gelfoam) into the amniotic cavity, antibiotic administration, and perioperative tocolysis. Weekly assessment of fluid status was performed and if oligohydramnios returned, patients were offered repeat amnioinfusion.

RESULTS

Fifteen women with PROM at 17.9 +/- 2.2 weeks' gestation (range 13-21 weeks) underwent this protocol. Spontaneous PROM was diagnosed in 14 patients and one had iatrogenic PROM after fetoscopy. Eight fetuses reached a viable gestational age (>or=24 weeks, 53%), with six of these newborn infants surviving to hospital discharge (30%) and two suffering intrauterine death. The average gestational age of delivery for survivors was 31.8 +/- 4.3 weeks, range 25 to 36 weeks. Talipes equivarus was observed in three survivors (50%). Bilateral hip dysplasia and torticollis were also diagnosed in two infants. Respiratory distress syndrome was diagnosed in all cases delivered at less than 32 weeks but was not observed thereafter. No adverse sequelae have been attributed to gelatin sponge exposure.

CONCLUSION

The observed survival rate with this interventional approach in a population at highest risk for pregnancy loss justifies further study of this treatment strategy. This protocol may not reduce the rate of musculoskeletal abnormalities.

A case controlled study of serial transabdominal amnioinfusions in the management of second trimester oligohydramnios due to premature rupture of membranes

OBJECTIVE

The aim of this study was to evaluate the role of transabdominal amnioinfusion in relieving oligohydramnios and improving pregnancy outcome.

STUDY DESIGN

Pregnant women with oligohydramnios amniotic fluid index (AFI<5) and premature rupture of membranes (PROM) from <27 weeks gestation were managed with serial transabdominal amnioinfusions. Under ultrasonic guidance, a 20-gauge needle was instilled in the uterine cavity and normal saline was infused until the AFI was normal. Repeat amnioinfusion was done weekly if oligohydramnios recurred. Amnioinfused cases were compared to cases with pPROM and oligohydramnios who had standard management.

RESULTS

The mean gestational age at first procedure was 22 weeks. The mean pre-procedure AFI was 1.1cm and post-procedure was 12 cm. The mean number of infusions was 2.4. The mean first infusion to delivery interval was 33 days. The amnioinfused group when compared to the control group had decreased perinatal mortality of 33% versus 83% (P=0.036, OR=0.4, 95% CI=0.17-0.93), neonatal mortality of 17% versus 71% (P=0.049, OR=0.26, 95% CI=0.07-0.97) and neonatal sepsis 86% versus 27%(P=0.049, OR=0.32, 95% CI=0.12-0.87) with no statistical difference in gestational age at rupture and delivery nor birthweight. Babies discharged home compared to non-survivors had a significant increase in gestational age at delivery, birthweight, NICU days and transabdominal amnioinfusions. Logistic regression showed that only transabdominal amnioinfusion and gestational age correlated with survival.

CONCLUSION

In selected cases of oligohydramnios with pPROM, transabdominal amnioinfusions may be associated with fluid retention and improved neonatal survival.

Antepartum prophylactic transabdominal amnioinfusion in preterm pregnancies complicated by oligohydramnios

OBJECTIVE

To assess the role of amnioinfusion in preterm pregnancies with oligohydramnios.

METHOD

29 women between 23 and 35 weeks' gestation were enrolled in the study. Transabdominal amnioinfusion was performed in 15 pregnancies, 14 patients were managed expectantly. The latency period and perinatal outcome of both groups were compared using the Mann-Whitney U-test and chi(2)-test.

RESULT

The amniotic fluid index significantly increased from a median value of 6 to 11 cm (P<0.0001) in the amnioinfusion group after amnioinfusion. The latency period of the amnioinfusion group was significantly longer (median 15 vs. 8 days P<0.05). Gestational week of the amnioinfusion group was earlier on admission (median 30.6 vs. 33.4 weeks, P=0.01) but at delivery this diversity disappeared (median 33.4 vs. 34.8 weeks, P=0.10). The perinatal outcomes of the two groups were similar.

CONCLUSION

Transabdominal amnioinfusion prolongs the latency period and improves perinatal outcome in preterm pregnancies complicated by oligohydramnios.

Neonatal complications of preterm premature rupture of membranes. Pathophysiology and management

Midtrimester PROM is an infrequent, yet potentially disastrous complication of pregnancy. The most likely neonatal complication is preterm delivery with associated morbidity and mortality risks. Unique neonatal complications following PPROM include skeletal deformations and pulmonary hypoplasia related to prolonged oligohydramnios exposure. A systematic approach to an infant with respiratory insufficiency following PPROM delivery is possible with an understanding of the pathophysiology of pulmonary hypoplasia. Neonatal management should include immediate resuscitation including surfactant replacement, with careful attention to techniques of mechanical ventilation to avoid early volutrauma. Adjunctive therapies directed at pulmonary hypertension may now permit survival of some infants with less severe forms of pulmonary hypoplasia.

Preterm premature rupture of the fetal membranes complicated by oligohydramnios

Preterm premature rupture of the fetal membranes complicated by oligohydramnios may have significant impact and sequelae on pregnancy outcome. In this article the role of amniotic fluid in fetal development, especially lung development, is reviewed; complications resulting from oligohydramnios are outlined; and the evaluated therapeutics and management schemes are delineated.

An in vitro model and case report that used gelatin sponge to restore amniotic fluid volume after spontaneous premature rupture of the membranes

OBJECTIVE

The purpose of this project was to study an in vitro model for plugging membrane defects with gelatin sponge and to develop a method with which to use this material to treat premature rupture of the membranes.

STUDY DESIGN

Fetal membranes were fixed over the opening of a flask that was filled with saline solution and gelatin sponge. Defects of various sizes were created, and the usefulness of differing sizes of gelatin sponge to obstruct the defects was observed. This technique was then applied to a case of previable, spontaneous premature rupture of the membranes.

RESULTS

Fifteen amniotomies were performed in the in vitro model. The gelatin sponge obstructed all defects less than 7 mm in length, when pieces up to 1 x 1 cm in dimension (n = 8 amniotomies) were used. For larger defects or those defects with a complex shape (such as cruciate), gelatin sponge was not effective at arresting fluid loss (n = 4 amniotomies). An inspection of larger gelatin sponge pieces, after instillation through a 12-gauge angiocatheter, revealed 36% (15 of 42 pieces) of 1 x 1 - cm pieces remained intact. A case of spontaneous, previable premature rupture of the membranes was treated with this material. A favorable outcome was observed.

CONCLUSION

Gelatin sponge is successful at arresting the egress of fluid through membrane defects when smaller defects are present. Complex or larger linear defects may not be treated by this method alone and necessitate adjuvant therapies. This therapeutic strategy can be applied to cases of previable, spontaneous premature rupture of the membranes.