Kitty W M Bloemenkamp

Leiden University Medical Centre, Leyden, South Holland, Netherlands

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Publications (142)805.11 Total impact

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    ABSTRACT: Objective The Disproportionate Intrauterine Growth Intervention Trial at Term (DIGITAT trial) showed that in women with suspected intrauterine growth restriction (IUGR) at term, there were no substantial outcome differences between induction of labour and expectant monitoring. The objective of the present analysis is to evaluate whether maternal or fetal markers could identify IUGR fetuses who would benefit from early labour induction. Study design The DIGITAT trial was a multicenter, parallel and open-label randomised controlled trial in women who had a singleton pregnancy beyond 36 + 0 weeks’ gestation with suspected IUGR (n = 650). Women had been randomly allocated to either labour induction or expectant monitoring. The primary outcome was a composite measure of adverse neonatal outcome, defined as neonatal death before hospital discharge, Apgar score <7, umbilical artery pH <7.05, or admission to neonatal intensive care. Using logistic regression modelling, we investigated associations between outcome and 17 markers, maternal characteristics and fetal sonographic and Doppler velocimetry measurements, all collected at study entry. Results 17 (5.3%) infants in the induction group had an adverse neonatal outcome compared to 20 (6.1%) in the expectant monitoring group. The only potentially informative marker for inducing labour was maternal pre-pregnancy body mass index (BMI). Otherwise, we observed at best weak associations between a benefit from labour induction and maternal age, ethnicity, smoking, parity, pregnancy-induced hypertension or preeclampsia, Bishop score and gestational age, or fetal sonographic markers (gender, estimated fetal weight, body measurements, oligohydramnios, or umbilical artery pulsatility index and end diastolic flow). Conclusion In late preterm and term pregnancies complicated by suspected intrauterine growth restriction, most of the known prognostic markers seem unlikely to be helpful in identifying women who could benefit from labour induction, except for maternal pre-pregnancy BMI.
    European Journal of Obstetrics & Gynecology and Reproductive Biology. 01/2014; 172:20–25.
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    ABSTRACT: Objective The aim of this study is to investigate which non-classic cardiovascular biomarkers are associated with persistent endothelial dysfunction after pregnancy in women with a history of hypertensive pregnancy disorders compared to women with uncomplicated pregnancies. Study design Systematic review and meta-analysis of observational studies. A search was performed in PubMed, Embase, Cochrane and Cinahl including articles from inception to 27 February 2013. Included were cohort studies and case-control studies. Cases were women with a history of hypertension in pregnancy, control subjects were women with a history of uncomplicated pregnancies. Of the 3136 found, 21 studies on 16 non-classic cardiovascular biomarkers are described in this review; 12 studies on 5 biomarkers were included in the meta-analysis. Results Women with a history of hypertensive pregnancy disorders had a higher homocysteine level compared to women with a history of uncomplicated pregnancies (5 studies; pooled mean difference 0.77ng/ml; 95% confidence interval 0.27 to 1.26; p <0.01). For the other non-classic cardiovascular biomarkers including markers in areas of inflammation, thrombosis and angiogenesis, we found no significant differences. Conclusion This review and meta-analysis showed that women with a history of hypertensive pregnancy disorders have higher homocysteine levels compared to women with a history of uncomplicated pregnancies. These data suggest persistent endothelial alteration after pregnancies complicated by hypertensive disorders.
    American journal of obstetrics and gynecology 01/2014; · 3.28 Impact Factor
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    ABSTRACT: Objective Women with late preterm premature rupture of membranes (PROM) have an increased risk that their child will develop neonatal sepsis. We evaluated whether neonatal sepsis can be predicted from antepartum parameters in these women. Study design: We used multivariable logistic regression to develop a prediction model. Data were obtained from two recent randomized controlled trials on induction of labor versus expectant management in late preterm PROM (PPROMEXIL trials, (ISRCTN29313500 and ISRCTN05689407). Data from randomized as well as non-randomized women, who consented to the use of their medical data, were used. We evaluated 13 potential antepartum predictors for neonatal sepsis. Missing data were imputed. Discriminative ability of the model was expressed as the area under the receiver operating characteristic (ROC) curve and a calibration with both a calibration plot and the Hosmer and Lemeshow goodness-of-fit test. Overall performance of the prediction model was quantified as the scaled Brier score. Results We studied 970 women. Thirty-three (3.4%) neonates suffered neonatal sepsis. Maternal age (OR 1.09 per year), maternal CRP level (OR 1.01 per mmol/l), maternal temperature (OR 1.80 per °Celsius) and positive GBS culture (OR 2.20) were associated with an increased risk of neonatal sepsis. The model had an area under the ROC-curve of 0.71. The model had both a good calibration and accuracy. Conclusions Antepartum parameters aid in the more precise prediction of the risk of neonatal sepsis in women with late preterm PPROM.
    European journal of obstetrics, gynecology, and reproductive biology 01/2014; · 1.97 Impact Factor
  • American Journal of Obstetrics and Gynecology. 01/2014; 210(1):S2–S3.
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    ABSTRACT: Objective Increasingly, maternal administration of 17-α-hydroxyprogesterone caproate (17-OHPC) is utilized to prevent preterm birth, but the fetal safety of 17-OHPC is still a matter of concern. This study aimed to assess whether exposure to 17-OHPC during the second and third trimesters of pregnancy affects fetal biometry in twin gestations. Methods This study included a subset of women with a twin pregnancy who had been previously included in a randomized clinical trial comparing the effectiveness of 17-OHPC and placebo on neonatal outcomes and preterm birth rates in multiple pregnancy. In the present study, the individual growth patterns of femur length, head circumference and abdominal circumference were compared between fetuses of women who had been randomized to receive weekly injections of either 17-OHPC (n = 52) or placebo (n = 58) at between 16–20 and 36 weeks' gestation. ResultsThe three biometric variables assessed developed similarly in fetuses in both the group exposed to 17-OHPC and the placebo group during the second half of pregnancy. Birth weight adjusted for parity and fetal sex was also comparable between groups. Conclusion The use of 17-OHPC has no adverse effects on fetal biometry and birth weight in twins. Copyright © 2013 ISUOG. Published by John Wiley & Sons Ltd.
    Ultrasound in Obstetrics and Gynecology 09/2013; 42(3). · 3.56 Impact Factor
  • Mieke Ten Eikelder, Ben Willem J Mol, Kitty Bloemenkamp
    American journal of obstetrics and gynecology 08/2013; · 3.28 Impact Factor
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    ABSTRACT: Cardiovascular disease (CVD) is the leading cause of death in women in the western world. Several studies have described the association between hypertensive pregnancy disorders and CVD in later life. Our aim was to compare postpartum cardiovascular risk factors in women who had a shorter and women who had a longer exposure to endothelial activation during their term hypertensive pregnancy. We studied a subsample of women with pregnancy-induced hypertension or mild preeclampsia at term, who had participated in the randomized HYPITAT trial comparing induction of labour (IOL cohort) (n=110) or expectant monitoring (EM cohort) (n=91). We assessed, 2.5 years postpartum, cardiovascular risk factors, i.e. blood pressure, anthropometrics, glucose, HbA1C, insulin, HOMA score, total cholesterol, HDL cholesterol, triglycerides, high sensitive CRP, micro-albumin and metabolic syndrome, and compared these risk factors between the induction and expectant groups. The mean time from randomization to delivery was 3.3 days in the induction group and 10.3 days in the expectant group (p<.001), generating a difference in exposure of 7 days. After a mean follow-up period of 2.5 years, the prevalence of hypertension (IOL 34%; EM 37%, p=.66) and metabolic syndrome (IOL 26%; EM 27%, p=1.0) was similar in both groups. Furthermore, systolic and diastolic blood pressure, BMI, waist circumference, glucose, HbA1C, insulin, HOMA score, lipids, HsCRP-levels and micro-albumin were all comparable between women who had induction of labour and those who had expectant monitoring. In women with hypertensive disorders in pregnancy at term, induction of labour does not affect the clinical and biochemical cardiovascular profile at 2.5 years postpartum.
    European journal of obstetrics, gynecology, and reproductive biology 08/2013; · 1.97 Impact Factor
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    ABSTRACT: 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. 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. 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). In unselected women with a multiple pregnancy, prophylactic use of a cervical pessary does not reduce poor perinatal outcome. The Netherlands Organisation for Health Research and Development.
    The Lancet 08/2013; · 39.06 Impact Factor
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    ABSTRACT: Pregnancies complicated by intrauterine growth restriction (IUGR) are at increased risk for neonatal morbidity and mortality. The Dutch nationwide disproportionate intrauterine growth intervention trial at term (DIGITAT trial) showed that induction of labour and expectant monitoring were comparable with respect to composite adverse neonatal outcome and operative delivery. In this study we compare the costs of both strategies. A cost analysis was performed alongside the DIGITAT trial, which was a randomized controlled trial in which 650 women with a singleton pregnancy with suspected IUGR beyond 36 weeks of pregnancy were allocated to induction or expectant management. Resource utilization was documented by specific items in the case report forms. Unit costs for clinical resources were calculated from the financial reports of participating hospitals. For primary care costs Dutch standardized prices were used. All costs are presented in Euros converted to the year 2009. Antepartum expectant monitoring generated more costs, mainly due to longer antepartum maternal stays in hospital. During delivery and the postpartum stage, induction generated more direct medical costs, due to longer stay in the labour room and longer duration of neonatal high care/medium care admissions. From a health care perspective, both strategies generated comparable costs: on average €7106 per patient for the induction group (N=321) and €6995 for the expectant management group (N=329) with a cost difference of €111 (95%CI: €-1296 to 1641). Induction of labour and expectant monitoring in IUGR at term have comparable outcomes immediately after birth in terms of obstetrical outcomes, maternal quality of life and costs. Costs are lower, however, in the expectant monitoring group before 38 weeks of gestation and costs are lower in the induction of labour group after 38 weeks of gestation. So if induction of labour is considered to pre-empt possible stillbirth in suspected IUGR, it is reasonable to delay until 38 weeks, with watchful monitoring.
    European journal of obstetrics, gynecology, and reproductive biology 08/2013; · 1.97 Impact Factor
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    ABSTRACT: To assess the safety and effectiveness of a transcervical Foley catheter compared to vaginal prostaglandin E2 inserts for term induction of labour. We conducted an open-label randomized controlled trial in five hospitals in the Netherlands. Women with a singleton term pregnancy in cephalic presentation, intact membranes, unfavourable cervix, and no prior caesarean section were enrolled. Participants were randomly allocated by a web-based randomization system to induction of labour with a 30ml Foley catheter or 10mg slow-release vaginal prostaglandin E2 inserts in a 1:1 ratio. Due to the nature of the intervention this study was not blinded. The primary outcome was the caesarean section rate. Secondary outcomes were maternal and neonatal morbidity and time from intervention to birth. Additionally, we carried out a systematic review and meta-analysis of similar studies. We analyzed 226 women: 107 received a Foley catheter and 119 inserts. Caesarean section rates were comparable (20% versus 22%, RR 0.90, 95% CI 0.54-1.50). Secondary outcomes showed no differences. We observed no serious maternal or neonatal morbidity. Meta-analysis showed comparable caesarean section rates, but significantly fewer cases of hyperstimulation during the ripening phase when a Foley catheter was used. We found, in this relatively small study, no differences in effectiveness and safety of induction of labour with a Foley catheter and 10mg slow release vaginal prostaglandin E2 inserts. Meta-analysis confirmed a comparable caesarean section rate, and showed fewer cases of hyperstimulation when a Foley catheter was used.
    European journal of obstetrics, gynecology, and reproductive biology 07/2013; · 1.97 Impact Factor
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    ABSTRACT: Preeclampsia is associated with increased levels of the circulating antiangiogenic factor sFlt-1 and with an excessive shedding of placenta-derived multinucleated syncytial aggregates into the maternal circulation. However, it remains unclear whether these aggregates are transcriptionally active in the maternal organs and can, therefore, contribute to the systemic manifestations of preeclampsia. In this study, we measured placental soluble fms-like tyrosine kinase-1 (sFlt-1) mRNA levels in preeclamptic- and control placentas and performed RNA in situ hybridization to localize the main placental expression site of sFlt-1 mRNA. Because the maternal lung is the first capillary bed that circulating syncytial aggregates traverse, we studied the presence and persistence of placental material in lungs of preeclamptic and control subjects. To confirm the placental origin of these aggregates in maternal lungs, immunohistochemistry for the placenta-specific marker hCG (human chorionic ghonadotropin) and Y chromosome in situ hybridization were performed. Using human placental tissue, we found that syncytial knots are the principal site of expression of the antiangiogenic factor sFlt-1. In addition, autopsy material obtained from women with preeclampsia (n=9) showed significantly more placenta-derived syncytial aggregates in the lungs than in control subjects (n=26). Importantly, these aggregates still contained the antiangiogenic factor sFlt-1 after their entrapment in the maternal lungs. The current study confirms the important role of syncytial knots in placental sFlt-1 mRNA production. In addition, it shows a significant association between preeclampsia and larger quantities of sFlt-1 containing syncytial aggregates in maternal lungs, suggesting that the transfer of syncytial aggregates to the maternal compartment may contribute to the systemic endothelial dysfunction that characterizes preeclampsia.
    Hypertension 07/2013; · 6.87 Impact Factor
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    ABSTRACT: Objectives To assess effectiveness and safety of Foley catheter versus vaginal misoprostol for term induction of labor.Study Design This trial randomly allocated women with singleton term pregnancy to 30-mL Foley catheter or 25-μg vaginal misoprostol tablets. Primary outcome was cesarean delivery rate. Secondary outcomes were maternal and neonatal morbidity and time to birth. Additionally, a systematic review was conducted.Results Fifty-six women were allocated to Foley catheter, 64 to vaginal misoprostol tablets. Cesarean delivery rates did not differ significantly (25% Foley versus 17% misoprostol; relative risk [RR] 1.46, 95% confidence interval [CI] 0.72 to 2.94), with more cesarean deliveries due to failure to progress in the Foley group (14% versus 3%; RR 4.57, 95% CI 1.01 to 20.64). Maternal and neonatal outcomes were comparable. Time from induction to birth was longer in the Foley catheter group (36 hours versus 25 hours; p < 0.001). Meta-analysis showed no difference in cesarean delivery rate and reduced vaginal instrumental deliveries and hyperstimulation in the Foley catheter group. Other outcomes were not different.Conclusion Our trial and meta-analysis showed no difference in cesarean delivery rates and less hyperstimulation with fetal heart rate changes and vaginal instrumental deliveries when using Foley catheter, thereby supporting potential advantages of the Foley catheter over misoprostol as ripening agent.
    American Journal of Perinatology 04/2013; · 1.57 Impact Factor
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    ABSTRACT: Introduction In preeclampsia (PE), the kidney is one of the major target organs. Growing evidence suggests PE increases the risk of subsequent microalbuminuria and end-stage renal disease (ESRD). Endotheliosis and podocyte changes due to anti-angiogenic factors seem to be salient features of PE. However, it is unknown whether chronic lesions are present in PE patients that could contribute to this increased risk. Objectives We hypothesized that women with PE and young women with chronic hypertension might show similarity in renal lesions. Furthermore, we investigated if the number of podocytes within the kidney is decreased under these different circumstances. Methods We performed a search for renal autopsy-tissues using a nationwide computerized database (PALGA) to collect a unique large cohort of preeclamptic patients (n = 11). Three control groups were included consisting of young women who died during pregnancy without hypertension (n = 25) and non-pregnant controls with (n = 14) and without (n = 13) chronic hypertension. WT-1 staining was used to quantify the number of podocytes. Results Women with PE had MPGN-like lesions without immune-deposits. Tram tracking and podocyte changes were exclusively observed in these patients. Endotheliosis was significantly more present in PE, but sporadically seen in pregnant- and hypertensive controls. Chronic ischaemic lesions were predominantly found in young women with chronic hypertension, and not in PE and other controls. No differences were found in glomerular podocyte number between the study groups. Conclusion All women with PE had MPGN-like lesions in their kidneys which was therefore regarded characteristic for PE. In contrast, no chronic lesions were observed in PE which could explain the increased risk of impaired renal function later in life. Interestingly, we demonstrated no difference in podocyte number between study groups. These results might suggest that neither persistent hypertension or dysbalance in angiogenic factors (i.e. preeclampsia) cause an observable change in podocyte number within the kidney.
    Pregnancy Hypertension: An International Journal of Women's Cardiovascular Health. 04/2013; 3(2):79.
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    ABSTRACT: BACKGROUND: Induction of labour is a common obstetric procedure. At present, different methods are used for induction of labour in women with an unfavourable cervix. Recently, we showed that in term women with an unfavorable cervix the use of a Foley catheter in comparison with vaginal Prostaglandin E2 gel, results in a comparable vaginal delivery rate. A meta-analysis on the subject indicated lower rates of hyperstimulation, and probably as a sequel fewer cases of postpartum haemorrhage. Misoprostol (PgE1) is another type of prostaglandin frequently used for labour induction, recommended by the international federation of gynaecology and obstetrics (FIGO). Misoprostol can be administered by vaginal, rectal and oral route. There is evidence that oral administration results in less asphyxia and hyperstimulation than vaginal administration. At present, valid comparisons between oral misoprostol and Foley catheter are lacking. Therefore, we propose a randomised controlled trial comparing Foley catheter to oral misoprostol in order to assess safety and cost-effectiveness. METHODS: We plan a multicentre, randomised, controlled, open-label clinical trial among term pregnant women with a vital singleton in cephalic presentation, unfavorable cervix, intact membranes and an indication for induction of labour. After informed consent, women will be randomly allocated by a webbased randomisation system to transcervical Foley catheter or oral misoprostol (50 mcg every 4 hours). The primary outcome will be a composite of complications of uterine hyperstimulation, i.e. post partum haemorrhage and asphyxia. Secondary outcomes are mode of delivery, maternal and neonatal morbidity, costs and women's preference. Serious adverse events such as severe maternal or neonatal morbitity or mortality will be monitored and reported to an independent data safety monitory board. With a sample size of 1860 women we will be able to demonstrate a 5% non-inferiority of the Foley catheter as compared to misoprostol for the composite outcome. DISCUSSION: Worldwide, various methods are being used for labour induction. Results of the proposed trial will contribute to the answer which method of induction of labour is most safe, cost-effective, and patient friendly and will help to construct evidence based guidelines.Trial registration: The Netherlands Trial Register NTR3466,
    BMC Pregnancy and Childbirth 03/2013; 13(1):67. · 2.52 Impact Factor
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    ABSTRACT: OBJECTIVE: The purpose of this study was to determine cardiovascular risk factors in women with a history of hypertensive pregnancy disorders at term, 2.5 years after pregnancy. STUDY DESIGN: In a multicenter cohort study in the Netherlands between June 2008 and November 2010, cardiovascular risk factors were compared between women with a history of hypertensive pregnancy disorders at term (HTP cohort, n=306) and women with a history of normotensive pregnancies at term (NTP cohort, n=99). HTP women had participated in a randomized, longitudinal trial assessing the effectiveness of induction of labor in women with hypertensive pregnancy disorders at term. All women were assessed 2.5 years after pregnancy for blood pressure, anthropometrics, glucose, HbA1C, insulin, HOMA score, total cholesterol, HDL cholesterol, triglycerides, high sensitive CRP and micro-albumin and metabolic syndrome. RESULTS: After a mean follow-up period of 2.5 years, hypertension (HTP, 34%; NTP, 1%; P<.001) and metabolic syndrome (HTP, 25%; NTP, 5%; P<.001) were more prevalent in HTP women compared with NTP women. HTP women had significantly higher systolic and diastolic blood pressure, higher BMI and waist circumference. Glucose, HbA1C, insulin, HOMA score, total cholesterol, triglycerides and high sensitive CRP-levels were significantly higher and HDL cholesterol was significantly lower in HTP women. CONCLUSIONS: In women with a history of hypertensive pregnancy disorders at term hypertension and metabolic syndrome are more common, and they have higher levels of biochemical cardiovascular risk factors 2.5 years after pregnancy.
    American journal of obstetrics and gynecology 02/2013; · 3.28 Impact Factor
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    ABSTRACT: BACKGROUND Pre-eclampsia has a clear familial component, suggesting that the condition may be partly attributable to genetic susceptibility. The search for susceptibility genes has led to a drastic increase in the number of published studies associating genetic factors with pre-eclampsia. However, attempts to replicate these findings have yielded inconsistent results. This meta-analysis assessed the pooled effect of each genetic variant that is reproducibly associated with pre-eclampsia.METHODS Studies that assessed the association between genes and pre-eclampsia were searched in PubMed, Embase and Web of Science. We selected all genetic variants that were significantly associated with pre-eclampsia in an initial study and were subsequently independently reproduced in at least one additional study. All studies that assessed these reproduced variants were then included. The association between genetic variants and pre-eclampsia was calculated at the allele level, and the main measure of effect was a pooled odds ratio in a random-effects model.RESULTSThe literature search yielded 2965 articles, of which 542 investigated genetic associations in pre-eclampsia. We identified 22 replicated genetic variants, of which 7 remained significantly associated with pre-eclampsia following meta-analysis. These variants were in or near the following genes: ACE, CTLA4, F2, FV, LPL and SERPINE1.CONCLUSIONS This meta-analysis identified seven genetic variants associated with pre-eclampsia. Importantly, many of these variants are also risk factors for developing cardiovascular disease, revealing that pre-eclampsia and cardiovascular disease have shared genetic risk factors. The contribution of the identified genetic variants in the pathogenesis of pre-eclampsia should be the focus of future studies.
    Human Reproduction Update 01/2013; · 9.23 Impact Factor
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    ABSTRACT: In threatened preterm labor, maintenance tocolysis with nifedipine, after an initial course of tocolysis and corticosteroids for 48 hours, may improve perinatal outcome. To determine whether maintenance tocolysis with nifedipine will reduce adverse perinatal outcomes due to premature birth. APOSTEL-II (Assessment of Perinatal Outcome with Sustained Tocolysis in Early Labor) is a double-blind, placebo-controlled trial performed in 11 perinatal units including all tertiary centers in The Netherlands. From June 2008 to February 2010, women with threatened preterm labor between 26 weeks (plus 0 days) and 32 weeks (plus 2 days) gestation, who had not delivered after 48 hours of tocolysis and a completed course of corticosteroids, were enrolled. Surviving infants were followed up until 6 months after birth (ended August 2010). Randomization assigned 406 women to maintenance tocolysis with nifedipine orally (80 mg/d; n = 201) or placebo (n = 205) for 12 days. Assigned treatment was masked from investigators, participants, clinicians, and research nurses. Primary outcome was a composite of adverse perinatal outcomes (perinatal death, chronic lung disease, neonatal sepsis, intraventricular hemorrhage >grade 2, periventricular leukomalacia >grade 1, or necrotizing enterocolitis). Analyses were completed on an intention-to-treat basis. Mean (SD) gestational age at randomization was 29.2 (1.7) weeks for both groups. Adverse perinatal outcome was not significantly different between groups: 11.9% (24/201; 95% CI, 7.5%-16.4%) for nifedipine vs 13.7% (28/205; 95% CI, 9.0%-18.4%) for placebo (relative risk, 0.87; 95% CI, 0.53-1.45). In patients with threatened preterm labor, nifedipine-maintained tocolysis did not result in a statistically significant reduction in adverse perinatal outcomes when compared with placebo. Although the lower than anticipated rate of adverse perinatal outcomes in the control group indicates that a benefit of nifedipine cannot completely be excluded, its use for maintenance tocolysis does not appear beneficial at this time. Identifier: NTR1336.
    JAMA The Journal of the American Medical Association 01/2013; 309(1):41-7. · 29.98 Impact Factor
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    ABSTRACT: To investigate the association between overweight and severe acute maternal morbidity (SAMM) in a low-risk pregnant population. Nationwide case-control study. The Netherlands, august 2004 to august 2006. 1567 cases from initially primary care and 2994 women from primary care practices as controls, out of 371 012 women delivering in the Netherlands during the study period. Cases were women with SAMM obtained from a nationwide prospective study. All women in this cohort who initially had low-risk pregnancies were compared with low-risk women without SAMM to calculate odd ratios (ORs) to develop SAMM by body mass index (BMI) category. We divided body mass index in three overweight categories and calculated the ORs (95% CI) of total SAMM and per specific endpoint by logistic regression, with normal weight as reference. We adjusted for age, parity and socio-economic status. SAMM, defined as Intensive Care Unit (ICU)-admission, Uterine Rupture, Eclampsia or Major Obstetric Haemorrhage (MOH). SAMM was reported in 1567 cases which started as low-risk pregnancies. BMI was available in 1097 (70.0%) cases and 2994 control subjects were included. Analysis showed a dose response relation for overweight (aOR, 1.3; 95% CI, 1.0-1.5), obese (aOR, 1.4; 95% CI, 1.1-1.9) and morbidly obese (aOR, 2.1; 95% CI, 1.3-3.2) women to develop SAMM compared to normal weight. Sub analysis showed the same dose response relation for ICU-admission, Uterine Rupture and Eclampsia. We found no association for MOH. Overweight without pre-existent co-morbidity is an important risk-indicator for developing SAMM. This risk increases with an increasing body mass index.
    PLoS ONE 01/2013; 8(9):e74494. · 3.73 Impact Factor
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    ABSTRACT: Postpartum haemorrhage is a leading cause of maternal morbidity and mortality worldwide. Identifying risk indicators for postpartum haemorrhage is crucial to predict this life threatening condition. Another major contributor to maternal morbidity and mortality is pre-eclampsia. Previous studies show conflicting results in the association between pre-eclampsia and postpartum haemorrhage. The primary objective of this study was to investigate the association between pre-eclampsia and postpartum haemorrhage. Our secondary objective was to identify other risk indicators for postpartum haemorrhage in the Netherlands. A nationwide cohort was used, containing prospectively collected data of women giving birth after 19 completed weeks of gestation from January 2000 until January 2008 (n = 1 457 576). Data were extracted from the Netherlands Perinatal Registry, covering 96% of all deliveries in the Netherlands. The main outcome measure, postpartum haemorrhage, was defined as blood loss of ≥1000 ml in the 24 hours following delivery. The association between pre-eclampsia and postpartum haemorrhage was investigated with uni- and multivariable logistic regression analyses. Overall prevalence of postpartum haemorrhage was 4.3% and of pre-eclampsia 2.2%. From the 31 560 women with pre-eclampsia 2 347 (7.4%) developed postpartum haemorrhage, compared to 60 517 (4.2%) from the 1 426 016 women without pre-eclampsia (odds ratio 1.81; 95% CI 1.74 to 1.89). Risk of postpartum haemorrhage in women with pre-eclampsia remained increased after adjusting for confounders (adjusted odds ratio 1.53; 95% CI 1.46 to 1.60). Women with pre-eclampsia have a 1.53 fold increased risk for postpartum haemorrhage. Clinicians should be aware of this and use this knowledge in the management of pre-eclampsia and the third stage of labour in order to reach the fifth Millenium Developmental Goal of reducing maternal mortality ratios with 75% by 2015.
    PLoS ONE 01/2013; 8(12):e81959. · 3.73 Impact Factor

Publication Stats

1k Citations
805.11 Total Impact Points


  • 1995–2014
    • Leiden University Medical Centre
      • • Department of Obstetrics
      • • Department of Clinical Epidemiology
      Leyden, South Holland, Netherlands
  • 2011–2013
    • Academisch Medisch Centrum Universiteit van Amsterdam
      • • Academic Medical Center
      • • Department of Obstetrics & Gynecology
      Amsterdam, North Holland, Netherlands
    • Groene Hart Ziekenhuis
      Guda, South Holland, Netherlands
  • 2010–2013
    • VU University Medical Center
      • Department of Obstetrics and Gynecology
      Amsterdam, North Holland, Netherlands
  • 2012
    • Bronovo Hospital
      's-Gravenhage, South Holland, Netherlands
  • 2007–2011
    • University of Groningen
      • Department of Obstetrics and Gynaecology
      Groningen, Province of Groningen, Netherlands
  • 2004–2011
    • Erasmus MC
      • • Department of Internal Medicine
      • • Department of Obstetrics and Gynaecology
      Rotterdam, South Holland, Netherlands
  • 1997–1998
    • St. Joseph's Hospital
      Savannah, Georgia, United States
    • Leiden University
      Leyden, South Holland, Netherlands