Preterm birth is the leading cause of perinatal mortality and neonatal morbidity worldwide. Many factors have been associated with preterm birth, including parity. The aim of the present study was to ...investigate associations between parity and risk of spontaneous preterm birth.
We conducted a retrospective study including live singleton births (≥22 weeks) of women with a first, second, third, fourth or fifth pregnancy in The Netherlands from 2010 through 2014. Our primary outcome was risk of spontaneous preterm birth < 37 weeks. Secondary outcomes were spontaneous preterm birth < 32 and < 28 weeks.
We studied 802,119 pregnancies, including 30,237 pregnancies that ended spontaneously < 37 weeks. We identified an increased risk for spontaneous preterm birth < 37 weeks in nulliparous women (OR 1.95, 95% CI 1.89-2.00) and women in their fifth pregnancy (OR 1.26, 95% CI 1.13-1.41) compared to women in their second pregnancy. Similar results were seen for spontaneous preterm birth < 32 and < 28 weeks.
Our data show an independent association between nulliparity and spontaneous preterm birth < 37, < 32 and < 28 weeks. Furthermore, we observed an increased risk for spontaneous preterm birth in women in their fifth pregnancy, with highest risk for preterm birth at early gestational age.
Background Preterm birth is in quantity and in severity the most important contributor of perinatal morbidity and mortality both in well- and low-resource countries. Cervical pessary and cervical ...cerclage are both considered as preventive treatments in women at risk for preterm birth. We aim to evaluate whether a cervical pessary can replace cervical cerclage for preventing recurrent preterm birth in women with a prior preterm birth due to cervical insufficiency or in women with a prior preterm birth and a short cervix in the current pregnancy. Methods/design A nationwide open-label multicentre randomised clinical trial will be set up to study women with a singleton pregnancy and a prior preterm birth before 34 weeks of gestation. Women are eligible in case of previous preterm birth based on cervical insufficiency (primary intervention, <16 weeks) or in case of previous preterm birth and a short cervical length in current pregnancy ≤25 mm (secondary intervention, <24 weeks). Eligible women will be randomised to either cervical pessary or cervical cerclage. Both interventions will be removed at labour or at 36 weeks of gestational age, whatever comes first. The primary outcome will be delivery before 32 weeks. Secondary outcomes will be gestational age at birth, preterm birth rate before 24, 28, 34 and 37 weeks of gestation (overall and stratified by spontaneous or indicated delivery), premature rupture of membranes, use of tocolysis and/or corticosteroids during pregnancy, mode of delivery, maternal infections, maternal side effects, neonatal and maternal hospital admissions, and a composite of adverse perinatal outcomes including both morbidity and mortality. We assume an event rate of 20% preterm birth before 32 weeks for cerclage and use a non-inferiority margin of 10% for the cervical pessary. Using an alpha of 0.05 and power of 0.80 we need 2 groups of 200 women each. Discussion The outcome of this study will indicate the effectiveness and the cost-effectiveness of a cervical cerclage and of a cervical pessary. Trial registration Netherlands Trial Registry, NTR 4415. Date registered: 29th of January 2014.
Preterm birth is in quantity and in severity the most important topic in obstetric care in the developed world. Progestogens and cervical pessaries have been studied as potential preventive ...treatments with conflicting results. So far, no study has compared both treatments.
The Quadruple P study aims to compare the efficacy of vaginal progesterone and cervical pessary in the prevention of adverse perinatal outcome associated with preterm birth in asymptomatic women with a short cervix, in singleton and multiple pregnancies separately. It is a nationwide open-label multicentre randomized clinical trial (RCT) with a superiority design and will be accompanied by an economic analysis. Pregnant women undergoing the routine anomaly scan will be offered cervical length measurement between 18 and 22 weeks in a singleton and at 16-22 weeks in a multiple pregnancy. Women with a short cervix, defined as less than, or equal to 35 mm in a singleton and less than 38 mm in a multiple pregnancy, will be invited to participate in the study. Eligible women will be randomly allocated to receive either progesterone or a cervical pessary. Following randomization, the silicone cervical pessary will be placed during vaginal examination or 200 mg progesterone capsules will be daily self-administered vaginally. Both interventions will be continued until 36 weeks gestation or until delivery, whichever comes first. Primary outcome will be composite adverse perinatal outcome of perinatal mortality and perinatal morbidity including bronchopulmonary dysplasia, intraventricular haemorrhage grade III and IV, periventricular leukomalacia higher than grade I, necrotizing enterocolitis higher than stage I, Retinopathy of prematurity (ROP) or culture proven sepsis. These outcomes will be measured up until 10 weeks after the expected due date. Secondary outcomes will be, among others, time to delivery, preterm birth rate before 28, 32, 34 and 37 weeks, admission to neonatal intensive care unit, maternal morbidity, maternal admission days for threatened preterm labour and costs.
This trial will provide evidence on whether vaginal progesterone or a cervical pessary is more effective in decreasing adverse perinatal outcome in both singletons and multiples.
Trial registration number: NTR 4414 . Date of registration January 29th 2014.
The aim of this study was to study the biocompatibility of an injectable silk gel in the cervix in a rat model of pregnancy. The rationale is to study an injectable gel as an alternate treatment for ...cervical insufficiency. We further aimed to perform cervical injections via a vaginal route to mimic the clinical procedure of a cervical cerclage. We performed an in vivo study in pregnant female Sprague Dawley rats. Cervical procedures were performed using a customized speculum under general anesthesia. Injections were performed on gestational day 16. The responses to silk gel injections were compared to polyethylene terephthalate suture and saline controls on gestational day 19 and postpartum. The inflammatory response was evaluated by histology, PCR for inflammatory gene expression, and ELISA for protein levels of proinflammatory mediators. Silk gel injections were performed on 13 animals. All animals tolerated the procedure. Silk gel occupied 5% of the stroma after injection. Injected silk gel caused neither preterm birth nor prolonged pregnancy and had no effect on the kits. When comparing inflammatory responses, expression of inflammatory genes and proinflammatory proteins in the silk gel group was intermediate between saline (lowest) and cerclage suture (highest). Injectable silk gel was more inflammatory compared to saline injections but less inflammatory compared to the suture material used for cervical cerclage. This study is an important step toward development of an alternative treatment for cervical insufficiency.
Preterm birth is the leading cause of neonatal mortality and morbidity worldwide. Spontaneous preterm birth is a complex, multifactorial condition in which cervical dysfunction plays an important ...role in some women. Current treatment options for cervical dysfunction include cerclage and supplemental progesterone. In addition, cervical pessary is being studied in research protocols. However, cerclage, supplemental progesterone and cervical pessary have well known limitations and there is a strong need for alternate treatment options. In this review, we discuss two novel interventions to treat cervical dysfunction: (1) injectable, silk protein-based biomaterials for cervical tissue augmentation (injectable cerclage) and (2) a patient-specific pessary. Three-dimensional computer simulation of the cervix is performed to provide a biomechanical rationale for the interventions. Further development of these novel interventions could lead to new treatment options for women with cervical dysfunction.
Introduction
Mid‐trimester uterine artery resistance measured with Doppler sonography is predictive for iatrogenic preterm birth. In view of the emerging association between hypertensive disease in ...pregnancy and spontaneous preterm birth, we hypothesized that uterine artery resistance could also predict spontaneous preterm birth.
Material and methods
We performed a cohort study of women with singleton pregnancies. Uterine artery resistance was routinely measured at the 18‐22 weeks anomaly scan. Pregnancies complicated by congenital anomalies or intrauterine fetal death were excluded. We analyzed if the waveform of the uterine artery (no notch, unilateral notch or bilateral notch) was predictive for spontaneous and iatrogenic preterm birth, defined as delivery before 37 weeks of gestation. Furthermore, we assessed whether the uterine artery pulsatility index was associated with the risk of preterm birth.
Results
Between January 2009 and December 2016 we collected uterine Doppler indices and relevant outcome data in 4521 women. Mean gestational age at measurement was 19+6 weeks. There were 137 (3.0%) women with a bilateral and 213 (4.7%) with a unilateral notch. Mean gestational age at birth was 38+6 weeks. Spontaneous and iatrogenic preterm birth rates were 5.7% and 4.9%, respectively. Mean uterine artery resistance was 1.12 in the spontaneous preterm birth group compared with 1.04 in the term group (P = 0.004) The risk of preterm birth was increased with high uterine artery resistance (OR 2.9 per unit; 95% CI 2.4‐3.9). Prevalence of spontaneous preterm birth increased from 5.5% in women without a notch in the uterine arteries to 8.0% in women with a unilateral notch and 8.0% in women with a bilateral notch. For iatrogenic preterm birth, these rates were 3.9%, 13.6% and 23.4%, respectively. Likelihood ratios for the prediction of spontaneous preterm birth were 1.6 (95% CI 1.0‐2.6) and 1.9 (95% CI 1.0‐3.5) for unilateral and bilateral notches, respectively, and for iatrogenic preterm birth they were 3.6 (95% CI 2.5‐5.2) and 6.8 (95% CI 4.7‐9.9) for unilateral and bilateral notches, respectively. Of all women with bilateral notching, 31.4% delivered preterm.
Conclusions
Mid‐trimester uterine artery resistance measured at 18‐22 weeks of gestation is a weak predictor of spontaneous preterm birth.
PDF
