Risk Of Preterm Prelabour Rupture Research Articles

Cervical excisional treatment increases the risk of intraamniotic infection in subsequent pregnancy complicated by preterm prelabor rupture of membranes

Excisional treatment of cervical intraepithelial neoplasia or very early stages of cervical cancer increases the risk of preterm prelabor rupture of membranes in subsequent pregnancies. The risk increases with the length of the excised cone. The subset of cases with preterm prelabor rupture of membranes and a history of cervical excisional treatment could also be at higher risk of intraamniotic infection/inflammation. However, there is a paucity of relevant information on this subject. This study aimed to assess the differences in the rates of intraamniotic infection/inflammation and early-onset neonatal sepsis between singleton preterm prelabor rupture of membranes pregnancies without and with a history of cervical excisional treatment, and to investigate the association between these complications of preterm prelabor rupture of membranes and the excised cone length. This retrospective cohort study included 770 preterm prelabor rupture of membranes pregnancies in which transabdominal amniocentesis was performed as part of standard clinical management to assess the intraamniotic environment. The maternal and perinatal medical records of all included women were reviewed to obtain information on the absence or presence of history of cervical excisional treatment and neonatal outcomes. Women whose records contained any information on history of cervical excisional treatment were contacted by phone and in writing to inform them of the study and request permission to collect relevant information from their medical records. Women were divided into 4 subgroups according to the presence of microorganisms and/or their nucleic acids (through culturing and molecular biology methods) in amniotic fluid and/or intraamniotic inflammation (through amniotic fluid interleukin-6 concentration evaluation): intraamniotic infection (presence of both), sterile intraamniotic inflammation (intraamniotic inflammation alone), microbial invasion of the amniotic cavity without inflammation (presence of microorganisms and/or their nucleic acids in amniotic fluid alone), and negative amniotic fluid for infection/inflammation (absence of both). A history of cervical excisional treatment was found in 10% (76/765) of the women. Of these, 82% (62/76) had a history of only 1 treatment, and information on cone length was available for 97% (60/62) of them. Women with a history of cervical excisional treatment had higher rates of intraamniotic infection (with, 25% [19/76] vs without, 12% [85/689]; adjusted odds ratio, 2.5; adjusted P=.004), microbial invasion of the amniotic cavity without inflammation (with, 25% [19/76] vs without, 11% [74/689]; adjusted odds ratio, 3.1; adjusted P<.0001), and early-onset neonatal sepsis (with, 8% [11/76] vs without, 3% [23/689]; adjusted odds ratio, 2.9; adjusted P=.02) compared with those without such history. Quartiles of cone length (range: 3-32 mm) were used to categorize the women into 4 quartile subgroups (first: 3-8 mm; second: 9-12 mm; third: 13-17 mm; and fourth: 18-32 mm). Cone length of ≥18 mm was associated with higher rates of intraamniotic infection (with, 29% [5/15] vs without, 12% [85/689]; adjusted odds ratio, 3.0; adjusted P=.05), microbial invasion of the amniotic cavity without inflammation (with, 40% [6/15] vs without, 11% [74/689]; adjusted odds ratio, 6.1; adjusted P=.003), and early-onset neonatal sepsis (with, 20% [3/15] vs without, 3% [23/689]; adjusted odds ratio, 5.7; adjusted P=.02). History of cervical excisional treatment increases risks of intraamniotic infection, microbial invasion of the amniotic cavity without inflammation, and development of early-onset neonatal sepsis in a subsequent pregnancy complicated by preterm prelabor rupture of membranes.

The ChorioAnchor: Design and Testing of a Novel Chorioamniotic Anchoring Device to Enable Percutaneous Fetoscopic Surgery

Introduction: Percutaneous fetoscopic surgery is hampered by an increased risk of preterm prelabor rupture of membranes (PPROM). Recent surgical techniques have shown that suturing the chorioamniotic membranes following laparotomy and uterine exteriorization is associated with a lower risk of PPROM compared to percutaneous in utero surgery. This study presents the ChorioAnchor, a novel resorbable device that percutaneously anchors the chorioamniotic membranes to the uterine wall. Methods: Human factors testing and peel tests were used to simulate the worst-case in-use loading conditions, establishing the device strength requirements. Tensile testing was used to measure the time-zero strength of the device. Porcine cadaver testing was used to examine ultrasound visibility and acute handling characteristics. Short-term host response was examined through an acute 7-day implantation study in a rabbit model. Results: With a time-zero tensile strength of 47 N, the ChorioAnchor exceeded the established 4 N strength requirement. Both the ChorioAnchor and delivery device were seen to be clearly visible under ultrasound imaging. Short-term host response to the device was well within the range expected for this type of device. Conclusion: The ChorioAnchor meets its engineering requirements in the early stages of implantation. Future studies will examine the kinetics of degradation of the device in vitro and in vivo.

Streptococcus agalactiae do not penetrate human chorioamniotic membranes in vitro but alter their biomechanical properties.

Vaginal colonization with Streptococcus agalactiae (group B streptococci) is hypothesized to constitute a risk factor for preterm prelabor rupture of membranes. In vitro studies have shown that S. agalactiae strains isolated from infants with neonatal sepsis adhere to chorion cells of the human chorioamniotic membrane. However, it is still unknown whether S. agalactiae strains penetrate the chorioamniotic membranes and whether S. agalactiae colonization affects the biomechanical properties of the membranes and thus contributes to increased risk of preterm prelabor rupture. The aim of this in vitro study was to explore if different strains of S. agalactiae penetrate and affect the biomechanical properties of human chorioamniotic membranes. Three different strains of S. agalactiae were obtained, one from an early-onset neonatal infection, one from a case of preterm prelabor rupture of membranes and one from a healthy pregnant carrier. Chorioamniotic membranes from elective cesarean deliveries were either incubated with S. agalactiae or mounted in a two-chamber incubation cell generating a "maternal" and a "fetal" chamber and incubated with S. agalactiae in the maternal chamber. Subsequently the membranes were examined to evaluate S. agalactiae attachment, penetration and the effect on the biomechanical properties. At 5h after incubation, S. agalactiae adhered to the chorioamniotic membranes with increased number at 20h. Streptococcus agalactiae did not penetrate the membranes even after 20h of incubation. Streptococcus agalactiae increased the ultimate tensile stress needed to rupture the membranes and increased the work needed to rupture the membranes as well as the elastic modulus. Human chorioamniotic membranes constitute a physical barrier against S. agalactiae infections. Moreover, S. agalactiae infection leads to increased strength of the membranes.

Antibiotic prophylaxis during the second and third trimester to reduce adverse pregnancy outcomes and morbidity.

Several studies have suggested that prophylactic antibiotics given during pregnancy improved maternal and perinatal outcomes, while others have shown no benefit and some have reported adverse effects. To determine the effect of prophylactic antibiotics on maternal and perinatal outcomes during the second and third trimester of pregnancy for all women or women at risk of preterm delivery. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 April 2015) and reference lists of retrieved articles. Randomised controlled trials comparing prophylactic antibiotic treatment with placebo or no treatment for women in the second or third trimester of pregnancy before labour. We assessed trial quality and extracted data. The review included eight randomised controlled trials. Approximately 4300 women were recruited to detect the effect of prophylactic antibiotic administration on pregnancy outcomes. Primary outcomesAntibiotic prophylaxis did not reduce the risk of preterm prelabour rupture of membranes (risk ratio (RR) 0.31; 95% confidence interval (CI) 0.06 to 1.49 (one trial, 229 women), low quality evidence) or preterm delivery (RR 0.88; 95% CI 0.72 to 1.09 (six trials, 3663 women), highquality evidence). However, preterm delivery was reduced in the subgroup of pregnant women with a previous preterm birth who had bacterial vaginosis (BV) during the current pregnancy (RR 0.64; 95% CI 0.47 to 0.88 (one trial, 258 women)), but there was no reduction in the subgroup of pregnant women with previous preterm birth without BV during the pregnancy (RR 1.08; 95% CI 0.66 to 1.77 (two trials, 500 women)). A reduction in the risk of postpartum endometritis (RR 0.55; 95% CI 0.33 to 0.92 (one trial, 196 women)) was observed in high-risk pregnant women (women with a history of preterm birth, low birthweight, stillbirth or early perinatal death) and in all women (RR 0.53; 95% CI 0.35 to 0.82 (three trials, 627 women), moderate quality evidence). There was no difference in low birthweight (RR 0.86; 95% CI 0.53 to 1.39 (four trials; 978 women)) or neonatal sepsis (RR 11.31; 95% CI 0.64 to 200.79) (one trial, 142 women)); and blood culture confirming sepsis was not reported in any of the studies. Secondary outcomesAntibiotic prophylaxis reduced the risk of prelabour rupture of membranes (RR 0.34; 95% CI 0.15 to 0.78 (one trial, 229 women), low quality evidence) and gonococcal infection (RR 0.35; 95% CI 0.13 to 0.94 (one trial, 204 women)). There were no differences observed in other secondary outcomes (congenital abnormality; small-for-gestational age; perinatal mortality), whilst many other secondary outcomes (e.g. intrapartum fever needing treatment with antibiotics) were not reported in included trials.Regarding the route of antibiotic administration, vaginal antibiotic prophylaxis during pregnancy did not prevent infectious pregnancy outcomes. The overall risk of bias was low, except that incomplete outcome data produced high risk of bias in some studies. The quality of the evidence using GRADE was assessed as low for preterm prelabour rupture of membranes, high for preterm delivery, moderate for postpartum endometritis, low for prelabour rupture of membranes, and very low for chorioamnionitis. Intrapartum fever needing treatment with antibiotics was not reported in any of the included studies. Antibiotic prophylaxis did not reduce the risk of preterm prelabour rupture of membranes or preterm delivery (apart from in the subgroup of women with a previous preterm birth who had bacterial vaginosis). Antibiotic prophylaxis given during the second or third trimester of pregnancy reduced the risk of postpartum endometritis, term pregnancy with pre-labour rupture of membranes and gonococcal infection when given routinely to all pregnant women. Substantial bias possibly exists in the review's results because of a high rate of loss to follow-up and the small numbers of studies included in each of our analyses. There is also insufficient evidence on possible harmful effects on the baby. Therefore, we conclude that there is not enough evidence to support the use of routine antibiotics during pregnancy to prevent infectious adverse effects on pregnancy outcomes.

Antibiotic prophylaxis during the second and third trimester to reduce adverse pregnancy outcomes and morbidity.

Several studies have suggested that prophylactic antibiotics given during pregnancy improved maternal and perinatal outcomes, while others have shown no benefit and some have reported adverse effects. To determine the effect of prophylactic antibiotics on maternal and perinatal outcomes during the second and third trimester of pregnancy for all women or women at risk of preterm delivery. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 July 2014) and reference lists of retrieved articles. Randomised controlled trials comparing prophylactic antibiotic treatment with placebo or no treatment for women in the second or third trimester of pregnancy before labour. We assessed trial quality and extracted data. The review included seven randomised controlled trials. Approximately 2100 women were recruited to detect the effect of prophylactic antibiotic administration on pregnancy outcomes. Primary outcomesAntibiotic prophylaxis did not reduce the risk of preterm prelabour rupture of membranes (risk ratio (RR) 0.31; 95% confidence interval (CI) 0.06 to 1.49 (one trial, 229 women) low quality evidence) or preterm delivery (RR 0.85; 95% CI 0.64 to 1.14 (five trials, 1480 women) low quality evidence). However, preterm delivery was reduced in the subgroup of pregnant women with a previous preterm birth who had bacterial vaginosis (BV) during the current pregnancy (RR 0.64; 95% CI 0.47 to 0.88 (one trial, 258 women), but there was no reduction in the subgroup of pregnant women with previous preterm birth without BV during the pregnancy (RR 1.08; 95% CI 0.66 to 1.77 (two trials, 500 women)). A reduction in the risk of postpartum endometritis (RR 0.55; 95% CI 0.33 to 0.92 (one trial, 196 women)) was observed in high-risk pregnant women (women with a history of preterm birth, low birthweight, stillbirth or early perinatal death) and in all women (RR 0.53; 95% CI 0.35 to 0.82 (three trials, 627 women) moderate quality evidence). There was no difference in low birth weight (RR 0.86; 95% CI 0.53 to 1.39 (four trials; 978 women) or neonatal sepsis (RR 11.31; 95% CI 0.64 to 200.79); and blood culture confirming sepsis was not reported in any of the studies. Secondary outcomesAntibiotic prophylaxis reduced the risk of prelabour rupture of membranes (RR 0.34; 95% CI 0.15 to 0.78 (one trial, 229 women) low quality evidence) and gonococcal infection (RR 0.35; 95% CI 0.13 to 0.94 (one trial, 204 women)). There were no differences observed in other secondary outcomes (congenital abnormality; small-for-gestational age; perinatal mortality), whilst many other secondary outcomes (e.g. intrapartum fever needing treatment with antibiotics) were not reported in included trials.Regarding the route of antibiotic administration, vaginal antibiotic prophylaxis during pregnancy did not prevent infectious pregnancy outcomes. The overall risk of bias was low except that incomplete outcome data produced high risk of bias in some studies. The quality of the evidence using GRADE was assessed as low for preterm prelabour rupture of membranes, low for preterm delivery, moderate for postpartum endometritis, low for prelabour rupture of membranes, and very low for chorioamnionitis. Intrapartum fever needing treatment with antibiotics was not reported in any of the included studies. Antibiotic prophylaxis did not reduce the risk of preterm prelabour rupture of membranes or preterm delivery (apart from in the subgroup of women with a previous preterm birth who had bacterial vaginosis). Antibiotic prophylaxis given during the second or third trimester of pregnancy reduced the risk of postpartum endometritis, preterm rupture of membranes and gonococcal infection when given routinely to all pregnant women. Substantial bias possibly exists in the review's results because of a high rate of loss to follow-up and the small numbers of studies included in each of our analyses. There is also insufficient evidence on possible harmful effects on the baby. Therefore, we conclude that there is not enough evidence to recommend the use of routine antibiotics during pregnancy to prevent infectious adverse effects on pregnancy outcomes.

Antibiotics for treating bacterial vaginosis in pregnancy

Bacterial vaginosis is an imbalance of the normal vaginal flora with an overgrowth of anaerobic bacteria and a lack of the normal lactobacillary flora. Women may have symptoms of a characteristic vaginal discharge but are often asymptomatic. Bacterial vaginosis during pregnancy has been associated with poor perinatal outcomes and, in particular, preterm birth (PTB). Identification and treatment may reduce the risk of PTB and its consequences. To assess the effects of antibiotic treatment of bacterial vaginosis in pregnancy. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 May 2012), searched cited references from retrieved articles and reviewed abstracts, letters to the editor and editorials. Randomised trials comparing antibiotic treatment with placebo or no treatment, or comparing two or more antibiotic regimens in pregnant women with bacterial vaginosis or intermediate vaginal flora whether symptomatic or asymptomatic and detected through screening. Two review authors independently assessed trials for inclusion, trial quality and extracted data. We contacted study authors for additional information. We included 21 trials of good quality, involving 7847 women diagnosed with bacterial vaginosis or intermediate vaginal flora.Antibiotic therapy was shown to be effective at eradicating bacterial vaginosis during pregnancy (average risk ratio (RR) 0.42; 95% confidence interval (CI) 0.31 to 0.56; 10 trials, 4403 women; random-effects, T² = 0.19, I² = 91%). Antibiotic treatment also reduced the risk of late miscarriage (RR 0.20; 95% CI 0.05 to 0.76; two trials, 1270 women, fixed-effect, I² = 0%).Treatment did not reduce the risk of PTB before 37 weeks (average RR 0.88; 95% CI 0.71 to 1.09; 13 trials, 6491 women; random-effects, T² = 0.06, I² = 48%), or the risk of preterm prelabour rupture of membranes (RR 0.74; 95% CI 0.30 to 1.84; two trials, 493 women). It did increase the risk of side-effects sufficient to stop or change treatment (RR 1.66; 95% CI 1.02 to 2.68; four trials, 2323 women, fixed-effect, I² = 0%).In this updated review, treatment before 20 weeks' gestation did not reduce the risk of PTB less than 37 weeks (average RR 0.85; 95% CI 0.62 to 1.17; five trials, 4088 women; random-effects, T² = 0.06, I² = 49%).In women with a previous PTB, treatment did not affect the risk of subsequent PTB (average RR 0.78; 95% CI 0.42 to 1.48; three trials, 421 women; random-effects, T² = 0.19, I² = 72%).In women with abnormal vaginal flora (intermediate flora or bacterial vaginosis), treatment may reduce the risk of PTB before 37 weeks (RR 0.53; 95% CI 0.34 to 0.84; two trials, 894 women).One small trial of 156 women compared metronidazole and clindamycin, both oral and vaginal, with no significant differences seen for any of the pre-specified primary outcomes. Statistically significant differences were seen for the outcomes of prolongation of gestational age (days) (mean difference (MD) 1.00; 95% CI 0.26 to 1.74) and birthweight (grams) (MD 75.18; 95% CI 25.37 to 124.99) however these represent relatively small differences in the clinical setting.Oral antibiotics versus vaginal antibiotics did not reduce the risk of PTB (RR 1.09; 95% CI 0.78 to 1.52; two trials, 264 women). Oral antibiotics had some advantage over vaginal antibiotics (whether metronidazole or clindamycin) with respect to admission to neonatal unit (RR 0.63; 95% CI 0.42 to 0.92, one trial, 156 women), prolongation of gestational age (days) (MD 9.00; 95% CI 8.20 to 9.80; one trial, 156 women) and birthweight (grams) (MD 342.13; 95% CI 293.04 to 391.22; one trial, 156 women).Different frequency of dosing of antibiotics was assessed in one small trial and showed no significant difference for any outcome assessed. Antibiotic treatment can eradicate bacterial vaginosis in pregnancy. The overall risk of PTB was not significantly reduced. This review provides little evidence that screening and treating all pregnant women with bacterial vaginosis will prevent PTB and its consequences. When screening criteria were broadened to include women with abnormal flora there was a 47% reduction in preterm birth, however this is limited to two included studies.

Plasma vitamin C levels and risk of preterm prelabour rupture of membranes

Preterm prelabour rupture of membranes (PPROM) is a leading cause of preterm births. Its attendant contribution to maternal and perinatal morbidity and mortality makes it imperative to identify factors that may help prevent this condition. This study examined the association between plasma vitamin C concentration and the risk of (PPROM) amongst pregnant women in a tertiary hospital setting. This was a prospective cross sectional study conducted at the Obstetric and Gynaecology Department of University of Benin Teaching Hospital (UBTH), Benin City. The study was in two phases, first a pilot study to determine baseline plasma vitamin C concentration amongst pregnant women in UBTH was conducted. In the main study 80 pregnant women were recruited into two groups of those with PPROM (40 cases) and those without PPROM (40 controls) matched for gestational age. Plasma vitamin C concentration was determined for all study participants and their sociodemographic characters were used to generate a database for analysis. In the pilot study, plasma vitamin C concentration decreased with increasing gestational age of pregnancy. In the main study plasma vitamin C concentration was significantly lower in women with PPROM than controls without PPROM, 0.53 ± 0.05 vs. 0.58 ± 0.05 mg/dl; P = 0.0001. Both groups (case and control) were comparably matched in age, parity and social class. There was a significant association between low vitamin C levels and the occurrence of PPROM (95% CI 1.53-11.88; P = 0.008). Plasma vitamin C was found to be lower in women with PPROM. Low plasma vitamin C concentration may thus be an associated risk factor for PPROM. Hence improved dietary or drug supplements may be a useful adjunctive strategy to reducing the incidence of PPROM and its attendant adverse sequelae. While this intervention is advocated, further multicentre investigation of the effects of vitamin C on risk of preterm PROM is suggested.

Cord occlusion techniques for selective termination in monochorionic twins.

We wished to determine the optimal method for cord obliteration to perform selective reduction in complicated monochorionic (MC) twin pregnancies under different clinical conditions. For this purpose, we reviewed our experience and the available published literature and unpublished reports. Indications were a cardiac twin pregnancy, twins discordant for fetal anomaly, and severe feto-fetal transfusion syndrome where one twin had a very poor prognosis. Data were available for the following techniques: cord embolization, fetoscopic cord ligation, laser coagulation, monopolar coagulation and bipolar cautery. Unfortunately the data are heterogeneous, incomplete and reports are only sporadic. Cord embolization using coils or sclerosants has a high failure rate and can no longer be recommended. In 23 published cases of fetoscopic cord ligation a failure rate of 10% was reported. After successful ligation an overall fetal survival rate of 71% but a risk of preterm prelabor rupture of the membranes (PPROM) of 30% was documented. Four cases of monopolar coagulation have been published--all in a cardiac twin pregnancies. In three cases the abdominal aorta was coagulated prior to 20 weeks and complete cessation of flow was demonstrated. In 10 cases of bipolar cord coagulation, all procedures were technically successful. Nine of 10 were performed under ultrasound guidance through a single port. In 2 cases, frank PPROM occurred, leading to induction of labor. The other eight fetuses were born at 35 weeks or more. Nd:YAG coagulation of the cord was much more sporadically described; the success of the procedure seems to be clearly dependant on gestational age. In all our attempts prior to 20 weeks, we failed in only one out of 6 cases. In summary, there is little data to perform meaningful comparisons of available techniques for umbilical cord occlusion. Based on practical and technical considerations we use the following clinical algorithm: prior to 21 weeks, we attempt to coagulate the cord with Nd:YAG laser. If this is unsuccessful, or for gestations beyond 21 weeks, bipolar cord coagulation is currently our other method of choice. Sonoendoscopic cord ligation is reserved as backup procedure if neither of these methods are successful.