Temporizing management vs immediate delivery in early-onset severe preeclampsia between 28 and 34 weeks of gestation (TOTEM study): An open-label randomized controlled trial.

INTRODUCTION: There is little evidence to guide the timing of delivery of women with early-onset severe preeclampsia. We hypothesize that immediate delivery is not inferior for neonatal outcome but reduces maternal complications compared with temporizing management. MATERIAL AND METHODS: This Dutch multicenter open-label randomized clinical trial investigated non-inferiority for neonatal outcome of temporizing management as compared with immediate delivery (TOTEM NTR 2986) in women between 27+5 and 33+5 weeks of gestation admitted for early-onset severe preeclampsia with or without HELLP syndrome. In participants allocated to receive immediate delivery, either induction of labor or cesarean section was initiated at least 48 hours after admission. Primary outcomes were adverse perinatal outcome, defined as a composite of severe respiratory distress syndrome, bronchopulmonary dysplasia, culture proven sepsis, intraventricular hemorrhage grade 3 or worse, periventricular leukomalacia grade 2 or worse, necrotizing enterocolitis stage 2 or worse, and perinatal death. Major maternal complications were secondary outcomes. It was estimated 1130 women needed to be enrolled. Analysis was by intention-to-treat. RESULTS: The trial was halted after 35 months because of slow recruitment. Between February 2011 and December 2013, a total of 56 women were randomized to immediate delivery (n = 26) or temporizing management (n = 30). Median gestational age at randomization was 30 weeks. Median prolongation of pregnancy was 2 days (interquartile range 1-3 days) in the temporizing management group. Mean birthweight was 1435 g after immediate delivery vs 1294 g after temporizing management (P = .14). The adverse perinatal outcome rate was 55% in the immediate delivery group vs 52% in the temporizing management group (relative risk 1.06; 95% confidence interval 0.67-1.70). In both groups there was one neonatal death and no maternal deaths. In the temporizing treatment group, one woman experienced pulmonary edema and one placental abruption. Analyses of only the singleton pregnancies did not result in other outcomes. CONCLUSIONS: Early termination of the trial precluded any conclusions for the main outcomes. We observed that temporizing management resulted in a modest prolongation of pregnancy without changes in perinatal and maternal outcome. Conducting a randomized study for this important research question did not prove feasible.

The diagnostic value of fetal fibronectin testing in clinical practice.

AIM: To evaluate the clinical management to withhold treatment for preterm labor in symptomatic women with an intermediate cervical length and negative fetal fibronectin (fFN) testing. METHODS: A retrospective cohort study was performed in a tertiary care teaching hospital in the Netherlands. Pregnant women with a gestational age between 23+5 to 34+0 weeks, with the presence of regular uterine contractions accompanied by a cervical length between 15 and 30 mm and intact membranes, who underwent fFN testing were included to obtain the diagnostic value of fFN testing for preterm delivery within 7 days. RESULTS: Fetal fibronectin testing has an extremely high negative predictive value (100%) and sensitivity (100%) for delivery within 7 days, in singleton and multiple pregnancies. However, specificity (64%) and positive predictive value (10%) of fFN testing in singleton pregnancies are low. Blood present on the fFN sample does not affect the reliability of the fFN test; the negative predictive value remains 100%. CONCLUSION: Women with symptoms of early preterm labor, intact membranes, a cervical length between 15 and 30 mm and negative fFN testing do not deliver within 7 days. Administration of corticosteroids and tocolytics can safely be withhold. Furthermore, blood on the fFN sample does not change the reliability of the fFN test.

Balloon catheter for induction of labor in women with one previous cesarean and an unfavorable cervix.

INTRODUCTION: When women with a previous cesarean section and an unfavorable cervix have an indication for delivery, the choice is to induce labor or to perform a cesarean section. This study aims to assess the effectiveness and safety of a balloon catheter as a method of induction of labor in women with one previous cesarean section and an unfavorable cervix compared with an elective repeat cesarean section. MATERIAL AND METHODS: We performed a prospective cohort study in 51 hospitals in the Netherlands on term women with one previous cesarean section, a live singleton fetus in cephalic position, an unfavorable cervix and an indication for delivery. We recorded obstetric, maternal and neonatal characteristics. We compared the outcome of women who were induced with a balloon catheter with the outcome of women who delivered by elective repeat cesarean section. Main outcomes were maternal and neonatal morbidity. Mode of delivery was a secondary outcome for women who were induced. Adjusted odds ratios (aOR) were calculated using logistic regression, adjusted for potential confounders. RESULTS: Analysis was performed on 993 women who were induced and 321 women who had a repeat cesarean section (August 2011 until September 2012). Among the women who were induced, 560 (56.4%) delivered vaginally and 11 (1.1%) sustained a uterine rupture. Composite adverse maternal outcome (uterine rupture, severe postpartum hemorrhage or postpartum infection) occurred in 73 (7.4%) in the balloon and 14 (4.5%) women in the repeat cesarean section group (aOR 1.58, 95% confidence interval [CI] 0.85-2.96). Composite adverse neonatal outcome (Apgar score <7 at 5 minutes or umbilical pH <7.10) occurred in 57 (5.7%) and 10 (3.2%) neonates, respectively (aOR 1.40, 95% CI 0.87-3.48). Women who were induced had a shorter postpartum admission time (2.0 vs 3.0 days (P < 0.0001)). CONCLUSIONS: In women with a previous cesarean section and a need for delivery, induction of labor with a balloon catheter does not result in a significant increase in adverse maternal and neonatal outcomes as compared with planned cesarean section.

Continuous glucose monitoring during diabetic pregnancy (GlucoMOMS): A multicentre randomized controlled trial.

AIM: Diabetes is associated with a high risk of adverse pregnancy outcomes. Optimal glycaemic control is fundamental and is traditionally monitored with self-measured glucose profiles and periodic HbA1c measurements. We investigated the effectiveness of additional use of retrospective continuous glucose monitoring (CGM) in diabetic pregnancies. MATERIAL AND METHODS: We performed a nationwide multicentre, open label, randomized, controlled trial to study pregnant women with type 1 or type 2 diabetes who were undergoing insulin therapy at gestational age < 16 weeks, or women who were undergoing insulin treatment for gestational diabetes at gestational age < 30 weeks. Women were randomly allocated (1:1) to intermittent use of retrospective CGM or to standard treatment. Glycaemic control was assessed by CGM for 5-7 days every 6 weeks in the CGM group, while self-monitoring of blood glucose and HbA1c measurements were applied in both groups. Primary outcome was macrosomia, defined as birth weight above the 90th percentile. Secondary outcomes were glycaemic control and maternal and neonatal complications. RESULTS: Between July 2011 and September 2015, we randomized 300 pregnant women with type 1 (n = 109), type 2 (n = 82) or with gestational (n = 109) diabetes to either CGM (n = 147) or standard treatment (n = 153). The incidence of macrosomia was 31.0% in the CGM group and 28.4% in the standard treatment group (relative risk [RR], 1.06; 95% CI, 0.83-1.37). HbA1c levels were similar between treatment groups. CONCLUSIONS: In diabetic pregnancy, use of intermittent retrospective CGM did not reduce the risk of macrosomia. CGM provides detailed information concerning glycaemic fluctuations but, as a treatment strategy, does not translate into improved pregnancy outcome.

Nifedipine versus atosiban for threatened preterm birth (APOSTEL III): a multicentre, randomised controlled trial.

BACKGROUND: In women with threatened preterm birth, delay of delivery by 48 h allows antenatal corticosteroids to improve neonatal outcomes. For this reason, tocolytics are often administered for 48 h; however, there is no consensus about which drug results in the best maternal and neonatal outcomes. In the APOSTEL III trial we aimed to compare the effectiveness and safety of the calcium-channel blocker nifedipine and the oxytocin inhibitor atosiban in women with threatened preterm birth. METHODS: We did this multicentre, randomised controlled trial in ten tertiary and nine teaching hospitals in the Netherlands and Belgium. Women with threatened preterm birth (gestational age 25-34 weeks) were randomly assigned (1:1) to either oral nifedipine or intravenous atosiban for 48 h. An independent data manager used a web-based computerised programme to randomly assign women in permuted block sizes of four, with groups stratified by centre. Clinicians, outcome assessors, and women were not masked to treatment group. The primary outcome was a composite of adverse perinatal outcomes, which included perinatal mortality, bronchopulmonary dysplasia, sepsis, intraventricular haemorrhage, periventricular leukomalacia, and necrotising enterocolitis. Analysis was done in all women and babies with follow-up data. The study is registered at the Dutch Clinical Trial Registry, number NTR2947. FINDINGS: Between July 6, 2011, and July 7, 2014, we randomly assigned 254 women to nifedipine and 256 to atosiban. Primary outcome data were available for 248 women and 297 babies in the nifedipine group and 255 women and 294 babies in the atosiban group. The primary outcome occurred in 42 babies (14%) in the nifedipine group and in 45 (15%) in the atosiban group (relative risk [RR] 0·91, 95% CI 0·61-1·37). 16 (5%) babies died in the nifedipine group and seven (2%) died in the atosiban group (RR 2·20, 95% CI 0·91-5·33); all deaths were deemed unlikely to be related to the study drug. Maternal adverse events did not differ between groups. INTERPRETATION: In women with threatened preterm birth, 48 h of tocolysis with nifedipine or atosiban results in similar perinatal outcomes. Future clinical research should focus on large placebo-controlled trials, powered for perinatal outcomes. FUNDING: ZonMw (the Netherlands Organisation for Health Research and Development).

Induction of labour at term with oral misoprostol versus a Foley catheter (PROBAAT-II): a multicentre randomised controlled non-inferiority trial.

BACKGROUND: Labour is induced in 20-30% of all pregnancies. In women with an unfavourable cervix, both oral misoprostol and Foley catheter are equally effective compared with dinoprostone in establishing vaginal birth, but each has a better safety profile. We did a trial to directly compare oral misoprostol with Foley catheter alone. METHODS: We did an open-label randomised non-inferiority trial in 29 hospitals in the Netherlands. Women with a term singleton pregnancy in cephalic presentation, an unfavourable cervix, intact membranes, and without a previous caesarean section who were scheduled for induction of labour were randomly allocated to cervical ripening with 50 µg oral misoprostol once every 4 h or to a 30 mL transcervical Foley catheter. The primary outcome was a composite of asphyxia (pH ≤7·05 or 5-min Apgar score <7) or post-partum haemorrhage (≥1000 mL). The non-inferiority margin was 5%. The trial is registered with the Netherlands Trial Register, NTR3466. FINDINGS: Between July, 2012, and October, 2013, we randomly assigned 932 women to oral misoprostol and 927 women to Foley catheter. The composite primary outcome occurred in 113 (12·2%) of 924 participants in the misoprostol group versus 106 (11·5%) of 921 in the Foley catheter group (adjusted relative risk 1·06, 90% CI 0·86-1·31). Caesarean section occurred in 155 (16·8%) women versus 185 (20·1%; relative risk 0·84, 95% CI 0·69-1·02, p=0·067). 27 adverse events were reported in the misoprostol group versus 25 in the Foley catheter group. None were directly related to the study procedure. INTERPRETATION: In women with an unfavourable cervix at term, induction of labour with oral misoprostol and Foley catheter has similar safety and effectiveness. FUNDING: FondsNutsOhra.

Women's Experiences with and Preference for Induction of Labor with Oral Misoprostol or Foley Catheter at Term.

Objective We assessed experience and preferences among term women undergoing induction of labor with oral misoprostol or Foley catheter. Study Design In 18 of the 29 participating hospitals in the PROBAAT-II trial, women were asked to complete a questionnaire within 24 hours after delivery. We adapted a validated questionnaire about expectancy and experience of labor and asked women whether they would prefer the same method again in a future pregnancy. Results The questionnaire was completed by 502 (72%) of 695 eligible women; 273 (54%) had been randomly allocated to oral misoprostol and 229 (46%) to Foley catheter. Experience of the duration of labor, pain during labor, general satisfaction with labor, and feelings of control and fear related to their expectation were comparable between both the groups. In the oral misoprostol group, 6% of the women would prefer the other method if induction is necessary in future pregnancy, versus 12% in the Foley catheter group (risk ratio: 0.70; 95% confidence interval: 0.55-0.90; p = 0.02). Conclusion Women's experiences of labor after induction with oral misoprostol or Foley catheter are comparable. However, women in the Foley catheter group prefer more often to choose a different method for future inductions.

Which Factors Contribute to False-Positive, False-Negative, and Invalid Results in Fetal Fibronectin Testing in Women with Symptoms of Preterm Labor?

Objective We assessed the influence of external factors on false-positive, false-negative, and invalid fibronectin results in the prediction of spontaneous delivery within 7 days. Methods We studied symptomatic women between 24 and 34 weeks' gestational age. We performed uni- and multivariable logistic regression to estimate the effect of external factors (vaginal soap, digital examination, transvaginal sonography, sexual intercourse, vaginal bleeding) on the risk of false-positive, false-negative, and invalid results, using spontaneous delivery within 7 days as the outcome. Results Out of 708 women, 237 (33%) had a false-positive result; none of the factors showed a significant association. Vaginal bleeding increased the proportion of positive fetal fibronectin (fFN) results, but was significantly associated with a lower risk of false-positive test results (odds ratio [OR], 0.22; 95% confidence intervals [CI], 0.12-0.39). Ten women (1%) had a false-negative result. None of the investigated factors was significantly associated with a significantly higher risk of false-negative results. Twenty-one tests (3%) were invalid; only vaginal bleeding showed a significant association (OR, 4.5; 95% CI, 1.7-12). Conclusion The effect of external factors on the performance of qualitative fFN testing is limited, with vaginal bleeding as the only factor that reduces its validity.

Immediate delivery versus expectant monitoring for hypertensive disorders of pregnancy between 34 and 37 weeks of gestation (HYPITAT-II): an open-label, randomised controlled trial.

BACKGROUND: There is little evidence to guide the management of women with hypertensive disorders in late preterm pregnancy. We investigated the effect of immediate delivery versus expectant monitoring on maternal and neonatal outcomes in such women. METHODS: We did an open-label, randomised controlled trial, in seven academic hospitals and 44 non-academic hospitals in the Netherlands. Women with non-severe hypertensive disorders of pregnancy between 34 and 37 weeks of gestation were randomly allocated to either induction of labour or caesarean section within 24 h (immediate delivery) or a strategy aimed at prolonging pregnancy until 37 weeks of gestation (expectant monitoring). The primary outcomes were a composite of adverse maternal outcomes (thromboembolic disease, pulmonary oedema, eclampsia, HELLP syndrome, placental abruption, or maternal death), and neonatal respiratory distress syndrome, both analysed by intention-to-treat. This study is registered with the Netherlands Trial Register (NTR1792). FINDINGS: Between March 1, 2009, and Feb 21, 2013, 897 women were invited to participate, of whom 703 were enrolled and randomly assigned to immediate delivery (n=352) or expectant monitoring (n=351). The composite adverse maternal outcome occurred in four (1·1%) of 352 women allocated to immediate delivery versus 11 (3·1%) of 351 women allocated to expectant monitoring (relative risk [RR] 0·36, 95% CI 0·12-1·11; p=0·069). Respiratory distress syndrome was diagnosed in 20 (5·7%) of 352 neonates in the immediate delivery group versus six (1·7%) of 351 neonates in the expectant monitoring group (RR 3·3, 95% CI 1·4-8·2; p=0·005). No maternal or perinatal deaths occurred. INTERPRETATION: For women with non-severe hypertensive disorders at 34-37 weeks of gestation, immediate delivery might reduce the already small risk of adverse maternal outcomes. However, it significantly increases the risk of neonatal respiratory distress syndrome, therefore, routine immediate delivery does not seem justified and a strategy of expectant monitoring until the clinical situation deteriorates can be considered. FUNDING: ZonMw.

The predictive value of quantitative fibronectin testing in combination with cervical length measurement in symptomatic women.

BACKGROUND: The combination of the qualitative fetal fibronectin test and cervical length measurement has a high negative predictive value for preterm birth within 7 days; however, positive prediction is poor. A new bedside quantitative fetal fibronectin test showed potential additional value over the conventional qualitative test, but there is limited evidence on the combination with cervical length measurement. OBJECTIVE: The purpose of this study was to compare quantitative fetal fibronectin and qualitative fetal fibronectin testing in the prediction of spontaneous preterm birth within 7 days in symptomatic women who undergo cervical length measurement. STUDY DESIGN: We performed a European multicenter cohort study in 10 perinatal centers in 5 countries. Women between 24 and 34 weeks of gestation with signs of active labor and intact membranes underwent quantitative fibronectin testing and cervical length measurement. We assessed the risk of preterm birth within 7 days in predefined strata based on fibronectin concentration and cervical length. RESULTS: Of 455 women who were included in the study, 48 women (11%) delivered within 7 days. A combination of cervical length and qualitative fibronectin resulted in the identification of 246 women who were at low risk: 164 women with a cervix between 15 and 30 mm and a negative fibronectin test (<50 ng/mL; preterm birth rate, 2%) and 82 women with a cervix at >30 mm (preterm birth rate, 2%). Use of quantitative fibronectin alone resulted in a predicted risk of preterm birth within 7 days that ranged from 2% in the group with the lowest fibronectin level (<10 ng/mL) to 38% in the group with the highest fibronectin level (>500 ng/mL), with similar accuracy as that of the combination of cervical length and qualitative fibronectin. Combining cervical length and quantitative fibronectin resulted in the identification of an additional 19 women at low risk (preterm birth rate, 5%), using a threshold of 10 ng/mL in women with a cervix at <15 mm, and 6 women at high risk (preterm birth rate, 33%) using a threshold of >500 ng/mL in women with a cervix at >30 mm. CONCLUSION: In women with threatened preterm birth, quantitative fibronectin testing alone performs equal to the combination of cervical length and qualitative fibronectin. Possibly, the combination of quantitative fibronectin testing and cervical length increases this predictive capacity. Cost-effectiveness analysis and the availability of these tests in a local setting should determine the final choice.

Early nasogastric tube feeding in optimising treatment for hyperemesis gravidarum: the MOTHER randomised controlled trial (Maternal and Offspring outcomes after Treatment of HyperEmesis by Refeeding).

BACKGROUND: Hyperemesis gravidarum (HG), or intractable vomiting during pregnancy, is the single most frequent cause of hospital admission in early pregnancy. HG has a major impact on maternal quality of life and has repeatedly been associated with poor pregnancy outcome such as low birth weight. Currently, women with HG are admitted to hospital for intravenous fluid replacement, without receiving specific nutritional attention. Nasogastric tube feeding is sometimes used as last resort treatment. At present no randomised trials on dietary or rehydration interventions have been performed. Small observational studies indicate that enteral tube feeding may have the ability to effectively treat dehydration and malnutrition and alleviate nausea and vomiting symptoms. We aim to evaluate the effectiveness of early enteral tube feeding in addition to standard care on nausea and vomiting symptoms and pregnancy outcomes in HG patients. METHODS/DESIGN: The MOTHER trial is a multicentre open label randomised controlled trial ( www.studies-obsgyn.nl/mother ). Women ≥ 18 years hospitalised for HG between 5 + 0 and 19 + 6 weeks gestation are eligible for participation. After informed consent participants are randomly allocated to standard care with intravenous rehydration or early enteral tube feeding in addition to standard care. All women keep a weekly diary to record symptoms and dietary intake until 20 weeks gestation. The primary outcome will be neonatal birth weight. Secondary outcomes will be the 24-h Pregnancy Unique Quantification of Emesis and nausea score (PUQE-24), maternal weight gain, dietary intake, duration of hospital stay, number of readmissions, quality of life and side-effects. Also gestational age at birth, placental weight, umbilical cord plasma lipid concentration and neonatal morbidity will be evaluated. Analysis will be according to the intention to treat principle. DISCUSSION: With this trial we aim to clarify whether early enteral tube feeding is more effective in treating HG than intravenous rehydration alone and improves pregnancy outcome. TRIAL REGISTRATION NUMBER: NTR4197 . Date of registration: October 2(nd) 2013.

From Postpartum Haemorrhage Guideline to Local Protocol: A Study of Protocol Quality.

Objective Postpartum hemorrhage (PPH) has a continuously rising incidence worldwide, suggesting suboptimal care. An important step in optimizing care is the translation of evidence-based guidelines into comprehensive hospital protocols. However, knowledge about the quality of these protocols is lacking. The objective of this study was to evaluate the quality of PPH-protocols on structure and content in the Netherlands. Methods We performed an observational multicenter study. Eighteen PPH-protocols from 3 University Hospitals (UH), 8 Teaching Hospitals (TH) and 7 Non-Teaching hospitals (NTH) throughout the Netherlands were acquired. The structure of the PPH-protocols was assessed using the Appraisal of Guidelines for Research and Evaluation (AGREE-II) Instrument. The content was appraised using previously developed quality indicators, based on international guidelines and Advance-Trauma-Life-Support (ATLS)-based course instructions. Results The quality of the protocols for postpartum hemorrhage for both structure and content varied widely between different hospitals, but all of them showed room for improvement. The protocols scored mainly below average on the different items of the AGREE-II instrument (8 of the 10 items scored <4 on a 1-7 scale). Regarding the content, adoption of guideline recommendations in protocols was 46 %. In addition, a timely indication of 'when to perform' a recommendation was lacking in three-fourths of the items. Conclusion This study shows that the quality of the PPH-protocols for both structure and content in the Netherlands is suboptimal. This makes adherence to the guideline and ATLS-based course instructions difficult.

The capacity of mid-pregnancy cervical length to predict preterm birth in low-risk women: a national cohort study.

INTRODUCTION: We investigated the predictive capacity of mid-trimester cervical length (CL) measurement for spontaneous and iatrogenic preterm birth. MATERIAL AND METHODS: We performed a prospective observational cohort study in nulliparous women and low-risk multiparous women with a singleton pregnancy between 16(+0) and 21(+6) weeks of gestation. We assessed the prognostic capacity of transvaginally measured mid-trimester CL for spontaneous and iatrogenic preterm birth (<37 weeks) using likelihood ratios (LR) and receiver-operating-characteristic analysis. We calculated numbers needed to screen to prevent one preterm birth assuming different treatment effects. Main outcome measures were preterm birth <32, <34 and <37 weeks. RESULTS: We studied 11,943 women, of whom 666 (5.6%) delivered preterm: 464 (3.9%) spontaneous and 202 (1.7%) iatrogenic. Mean CL was 44.1 mm (SD 7.8 mm). In nulliparous women, the LRs for spontaneous preterm birth varied between 27 (95% CI 7.7-95) for a CL ≤ 20 mm, and 2.0 (95% CI 1.6-2.5) for a CL between 30 and 35 mm. For low-risk multiparous women, these LRs were 37 (95% CI 7.5-182) and 1.5 (95% CI 0.97-2.2), respectively. Using a cut-off for CL ≤ 30 mm, 28 (6.0%) of 464 women with spontaneous preterm birth were identified. The number needed to screen to prevent one case of preterm birth was 618 in nulliparous women and 1417 for low-risk multiparous women (40% treatment effect, cut-off 30 mm). CONCLUSION: In women at low risk of preterm birth, CL predicts spontaneous preterm birth. However, its isolated use as a screening tool has limited value due to low sensitivity.

Risk stratification with cervical length and fetal fibronectin in women with threatened preterm labor before 34 weeks and not delivering within 7 days.

OBJECTIVE: To stratify the risk of spontaneous preterm delivery using cervical length (CL) and fetal fibronectin (fFN) in women with threatened preterm labor who remained pregnant after 7 days. DESIGN: Prospective observational study. SETTING: Nationwide cohort of women with threatened preterm labor from the Netherlands. POPULATION: Women with threatened preterm labor between 24 and 34 weeks with a valid CL and fFN measurement and remaining pregnant 7 days after admission. METHODS: Kaplan-Meier and Cox proportional hazards models were used to estimate cumulative percentages and hazard ratios (HR) for spontaneous delivery. MAIN OUTCOME MEASURES: Spontaneous delivery between 7 and 14 days after initial presentation and spontaneous preterm delivery before 34 weeks. RESULTS: The risk of delivery between 7 and 14 days was significantly increased for women with a CL < 15 mm or a CL ≥15 to <30 mm and a positive fFN, compared with women with a CL ≥30 mm: HR 22.3 [95% confidence interval (CI) 2.6-191] and 14 (95% CI 1.8-118), respectively. For spontaneous preterm delivery before 34 weeks the risk was increased for women with a CL < 15 mm [HR 6.3 (95% CI 2.6-15)] or with a CL ≥15 to <30 mm with either positive fFN [HR 3.6 (95% CI 1.5-8.7)] or negative fFN [HR 3.0 (95% CI 1.2-7.1)] compared with women with a CL ≥ 30 mm. CONCLUSIONS: In women remaining pregnant 7 days after threatened preterm labor, CL and fFN results can be used in risk stratification for spontaneous delivery.

Pharmacokinetics of nifedipine slow-release during sustained tocolysis.

OBJECTIVE: The pharmacokinetics of nifedipine as a tocolytic agent has not been studied in great detail in pregnant women and has instead focused on immediate release tablets and gastrointestinal therapeutic system (GITS) tablets. The aim of this study was to determine nifedipine slow-release half-life and distribution volume in pregnant women and to compare these with pharmacokinetic parameters of nifedipine in non-pregnant subjects described in the literature. MATERIALS: This is a study parallel to a trial studying women with threatened preterm labor between 26 + 0 and 32 + 2 weeks after initial tocolysis and a completed course of corticosteroids, who were randomly allocated to maintenance nifedipine (slow-release tablets 20 mg 4 times daily) or placebo. Exclusion criteria for the pharmacokinetic study were contra-indications for nifedipine, impaired liver function, and concomitant intake of inhibitors or inducers of the cytochrome P450 3A4 isoenzyme. Blood samples for measuring nifedipine plasma concentrations were drawn at t = 0, t = 12 hours, t = 24 hours, t = 48 hours, t = 72 hours, t = 7 days, and t = 9 days. METHODS: Pharmacokinetic parameters were estimated using iterative two-stage Bayesian population pharmacokinetic analysis by MWPharm© software. The study was designed to establish a correlation between body weight and nifedipine plasma level. RESULTS: The pharmacokinetic parameters of nifedipine slow-release tablets were determined from the data of 8 pregnant women. Nifedipine slow-release had a half-life of 2 - 5 hours, a mean distribution volume of 6.2 ± 1.9 L/kg (calculated while using a fixed biological availability of 0.45 taken from the literature due to lack of intravenous data in this population) compared to a half-life of 6 - 11 hours, and a distribution volume of 1.2 - 1.3 L/kg described in non-pregnant subjects in the literature. None of the women delivered during study medication. Study medication was continued for the duration of the pharmacokinetic study (9 days) in all women. A correlation between nifedipine plasma levels and maternal body weight was not demonstrated. This may have been caused by lack of power. CONCLUSION: Pregnant subjects in this study, using nifedipine slow-release tablets, showed a larger volume of distribution and a shorter elimination half-life than for non-pregnant subjects as published in the literature.

What is the risk of preterm delivery after arrested preterm labor?

OBJECTIVE: The aim of this study is to assess if women with arrested preterm labor (PTL) have an increased risk of preterm delivery (PTD) compared with healthy pregnant women, and if digital examination, fetal fibronectin (fFn) and cervical length (CL) are prognostic markers for PTD after arrested PTL. STUDY DESIGN: Prospective-matched cohort study among women with arrested PTL (cases) and healthy pregnant women (controls). RESULTS: We included 74 index cases and 74 controls. PTD occurred in 20 (27%) index cases and in 5 (7%) controls (hazard ratio [HR], 4.5; 95% confidence interval [CI], 1.7-12). A dilatation of the cervix ≥ 1 cm (HR, 9.1 [95% CI, 3.3-25], an fFn positive status (HR, 13 [95% CI, 4.3-40]), and a CL < 15 mm (HR, 11 [95% CI, 3.1-38]) increased this risk in cases compared with controls. Knowledge of the fFn result had additional value over the cervical dilatation or CL in the prediction of persistent PTD, with an increased risk in case of a positive fFn test. CONCLUSION: Women stay at increased risk for PTD after arrested PTL. This risk further increased in case of ≥ 1 cm cervical dilatation, CL < 15 mm and/or a positive fFn status.

Randomized comparison of nifedipine and placebo in fibronectin-negative women with symptoms of preterm labor and a short cervix (APOSTEL-I Trial).

OBJECTIVE: To evaluate whether tocolysis with nifedipine can be omitted in women with symptoms of preterm labor, a shortened cervix, and negative fetal fibronectin test. STUDY DESIGN: A randomized noninferiority trial was performed in all Dutch perinatal centers. Women with symptoms of preterm labor between 24 and 34 weeks, intact membranes, cervical length between 10 and 30 mm, and negative fibronectin test were randomly allocated to nifedipine (80 mg/day) or placebo. The primary outcome was delivery within 7 days. Secondary outcomes were severe neonatal morbidity and mortality. We also followed all eligible nonrandomized women. RESULTS: We allocated 37 women to nifedipine and 36 women to placebo. In the nifedipine group, three women (8.1%) delivered within 7 days, compared with one woman (2.8%) in the placebo group (difference -5.3%; one-sided 95% confidence limit 4.5%). Median gestational age at delivery were respectively 37 + 0 (interquartile range [IQR] 34 + 6 to 38 + 5) and 38 + 2 (IQR 37 + 0 to 39 + 6) weeks (p = 0.008). In the nifedipine group, three pregnancies (8.1%) had a poor outcome; there were no poor outcomes in the placebo group. We observed similar trends in eligible nonrandomized women. CONCLUSION: In symptomatic women with preterm labor, a shortened cervix, and negative fibronectin test, placebo treatment is not inferior to tocolysis with nifedipine.

Cervical pessaries for prevention of preterm birth in women with a multiple pregnancy (ProTWIN): a multicentre, open-label randomised controlled trial.

BACKGROUND: In women with a multiple pregnancy, spontaneous preterm delivery is the leading cause of perinatal morbidity and mortality. Interventions to reduce preterm birth in these women have not been successful. We assessed whether a cervical pessary could effectively prevent poor perinatal outcomes. METHODS: We undertook a multicentre, open-label randomised controlled trial in 40 hospitals in the Netherlands. We randomly assigned women with a multiple pregnancy between 12 and 20 weeks' gestation (1:1) to pessary or control groups, using a web-based application with a computer-generated list with random block sizes of two to four, stratified by hospital. Participants and investigators were aware of group allocation. For women in the pessary group, a midwife or obstetrician inserted a cervical pessary between 16 and 20 weeks' gestation. Women in the control group did not receive the pessary, but otherwise received similar obstetrical care to those in the pessary group. The primary outcome was a composite of poor perinatal outcome: stillbirth, periventricular leucomalacia, severe respiratory distress syndrome, bronchopulmonary dysplasia, intraventricular haemorrhage, necrotising enterocolitis, proven sepsis, and neonatal death. Analyses were by modified intention to treat. This trial is registered in the Dutch trial registry, number NTR1858. FINDINGS: Between Sept 21, 2009, and March 9, 2012, 813 women underwent randomisation, of whom 808 were analysed (401 in the pessary group; 407 in the control group). At least one child of 53 women (13%) in the pessary group had poor perinatal outcome, compared with 55 (14%) in the control group (relative risk 0·98, 95% CI 0·69-1·39). INTERPRETATION: In unselected women with a multiple pregnancy, prophylactic use of a cervical pessary does not reduce poor perinatal outcome. FUNDING: The Netherlands Organisation for Health Research and Development.

Prediction of postpartum hemorrhage in women with gestational hypertension or mild preeclampsia at term.

OBJECTIVE: To assess whether postpartum hemorrhage can be predicted in women with gestational hypertension or mild preeclampsia at term. DESIGN: A cohort study in which we used data from our multicentre randomized controlled trial (HYPITAT trial). SETTING: The study was conducted in 38 hospitals in the Netherlands between 2005 and 2008. POPULATION: Women with gestational hypertension or mild preeclampsia at term (n = 1132). METHODS: An antepartum model (model A) and an antepartum/intrapartum model (model B) were created using logistic regression. The predictive capacity of the models was assessed with receiver operating characteristic analysis and calibration. MAIN OUTCOME MEASURE: Postpartum hemorrhage, defined as blood loss >1000 mL within 24 h after delivery. RESULTS: Postpartum hemorrhage occurred in 118 (10.4%) women. Maternal age (odds ratio 1.03), prepregnancy body mass index (odds ratio 0.96), and women with preeclampsia (odds ratio 1.5) were independent antepartum prognostic variables of postpartum hemorrhage. Intrapartum variables incorporated in the model were gestational age at delivery (odds ratio 1.2), duration of dilatation stage (odds ratio 1.1), and episiotomy (odds ratio 1.5). Model A and model B showed moderate discrimination, with areas under the receiver operating characteristic curve of 0.59 (95% confidence interval 0.53-0.64) and 0.64 (95% confidence interval 0.59-0.70), respectively. Calibration was moderate for model A (Hosmer-Lemeshow p = 0.26) but better for model B (Hosmer-Lemeshow p = 0.36). The rates of postpartum hemorrhage ranged from 4% (lowest 10%) to 22% (highest 10%). CONCLUSION: In the assessment of performance of a prediction model, calibration is more important than discriminative capacity. Our prediction model shows that for women with gestational hypertension or mild preeclampsia at term, distinction between low and high risk of developing postpartum hemorrhage is possible when antepartum and intrapartum variables are combined.

Nifedipine versus atosiban in the treatment of threatened preterm labour (Assessment of Perinatal Outcome after Specific Tocolysis in Early Labour: APOSTEL III-Trial).

BACKGROUND: Preterm birth is the most common cause of neonatal morbidity and mortality. Postponing delivery for 48 hours with tocolytics to allow for maternal steroid administration and antenatal transportation to a centre with neonatal intensive care unit facilities is the standard treatment for women with threatening preterm delivery in most centres. However, there is controversy as to which tocolytic agent is the drug of first choice. Previous trials have focused on tocolytic efficacy and side effects, and are probably underpowered to detect clinically meaningfull differences in neonatal outcome. Thus, the current evidence is inconclusive to support a balanced recommendation for clinical practice. This multicenter randomised clinical trial aims to compare nifedipine and atosiban in terms of neonatal outcome, duration of pregnancy and maternal side effects. METHODS/DESIGN: The Apostel III trial is a nationwide multicenter randomised controlled study. Women with threatened preterm labour (gestational age 25 - 34 weeks) defined as at least 3 contractions per 30 minutes, and 1) a cervical length of ≤ 10 mm or 2) a cervical length of 11-30 mm and a positive Fibronectin test or 3) ruptured membranes will be randomly allocated to treatment with nifedipine or atosiban. Primary outcome is a composite measure of severe neonatal morbidity and mortality. Secondary outcomes will be time to delivery, gestational age at delivery, days on ventilation support, neonatal intensive care (NICU) admittance, length admission in neonatal intensive care, total days in hospital until 3 months corrected age, convulsions, apnoea, asphyxia, proven meningitis, pneumothorax, maternal side effects and costs. Furthermore, an economic evaluation of the treatment will be performed. Analysis will be by intention to treat principle. The power calculation is based on an expected 10% difference in the prevalence of adverse neonatal outcome. This implies that 500 women have to be randomised (two sided test, ß 0.2 at alpha 0.05). DISCUSSION: This trial will provide evidence on the optimal drug of choice in acute tocolysis in threatening preterm labour. CLINICAL TRIAL REGISTRATION: NTR2947, date of registration: June 20th 2011.