Evaluation of 280,000 cases in Dutch midwifery practices: a descriptive study.

OBJECTIVE: To assess the nature and outcome of intrapartum referrals from primary to secondary care within the Dutch obstetric system. DESIGN: Descriptive study. SETTING: Dutch midwifery database (LVR1), covering 95% of all midwifery care and 80% of all Dutch pregnancies (2001-03). POPULATION: Low-risk women (280,097) under exclusive care of a primary level midwife at the start of labour either with intention to deliver at home or with a personal preference to deliver in hospital under care of a primary level midwife. METHODS: Women were classified into three categories (no referral, urgent referral and referral without urgency) and were related to maternal characteristics and to neonatal outcomes. MAIN OUTCOME MEASURES: Distribution of referral categories, main reasons for urgent referral, Apgar score at 5 minutes, perinatal death within 24 hours and referral to a paediatrician within 24 hours. RESULTS: In our study, 68.1% of the women completed childbirth under exclusive care of a midwife, 3.6% were referred on an urgency basis and 28.3% were referred without urgency. Of all referrals, 11.2% were on an urgency basis. The main reasons for urgent referrals were fetal distress and postpartum haemorrhage. The nonurgent referrals predominantly took place during the first stage of labour (73.6% of all referrals). Women who had planned a home delivery were referred less frequently than women who had planned a hospital delivery: 29.3 and 37.2%, respectively (P < 0.001). On average, the mean Apgar score at 5 minutes was high (9.72%) and the peripartum neonatal mortality was low (0.05%) in the total study group. No maternal deaths occurred. Adverse neonatal outcomes occurred most frequently in the urgent referral group, followed by the group of referrals without urgency and the nonreferred group. CONCLUSIONS: Risk selection is a crucial element of the Dutch obstetric system and continues into the postpartum period. The system results in a relatively small percentage of intrapartum urgent referrals and in overall satisfactory neonatal outcomes in deliveries led by primary level midwives.

[Sensible family planning: pitfalls and dilemmas]. / Verstandige gezinsplanning: valkuilen en dilemma's.

In a recent article in this journal it was stated that Dutch women were sensible in having their first child between the ages of 25 and 35 years. One of the conclusions was that associated health risks increase after the age of 35 but are still acceptable even at the age of 40. We demonstrate that these conclusions were based on flawed assumptions. Postponing pregnancy until after the age of 30 increases the risks of infertility and breast cancer. Motherhood at a later age is associated with an increase in obstetrical complications, miscarriage and other adverse effects on the child. Therefore, for couples planning a family with 2 children or more, it would be sensible to have the first pregnancy not long after the mother reaches the age of 30 years, or even earlier. Couples should be informed on the risks of late parenthood in order to be able to take the right decisions concerning family planning.

Behavioural and emotional problems in very preterm and very low birthweight infants at age 5 years.

BACKGROUND: Children born very preterm (VP; <32 weeks' gestation) or with very low birth weight (VLBW, <1500 g; hereafter called VP/VLBW) are at risk for behavioural and emotional problems during school age and adolescence. At school entrance these problems may hamper academic functioning, but evidence on their occurrence at this age in VP/VLBW children is lacking. AIM: To provide information on academic functioning of VP/VLBW children and to examine the association of behavioural and emotional problems with other developmental problems assessed by paediatricians. DESIGN, SETTING AND PARTICIPANTS: A cohort of 431 VP/VLBW children aged 5 years (response rate 76.1%) was compared with two large national samples of children of the same age (n = 6007, response rate 86.9%). OUTCOME MEASURES: Behavioural and emotional problems measured by the Child Behavior Checklist (CBCL), and paediatrician assessment of other developmental domains among VP/VLBW children. RESULTS: The prevalence rate of a CBCL total problems score in the clinical range was higher among VP/VLBW children than among children of the same age from the general population (13.2% v 8.7%, odds ratio 1.60 (95% confidence interval 1.18 to 2.17)). Mean differences were largest for social and attention problems. Moreover, they were larger in children with paediatrician-diagnosed developmental problems at 5 years, and somewhat larger in children with severe perinatal problems. CONCLUSION: At school entrance, VP/VLBW children are more likely to have behavioural and emotional problems that are detrimental for academic functioning. Targeted and timely help is needed to support them and their parents in overcoming these problems and in enabling them to be socially successful.

Is attrition bias a problem in neonatal follow-up?

AIM: To assess whether attrition rate influences outcome in the follow-up of very preterm infants. STUDY DESIGN: In a national follow-up study of infants born alive in 1983 in the Netherlands with a gestational age less than 32 weeks and/or a birth weight less than 1500 g, outcome was assessed separately for adolescents who responded early or late to a follow-up invitation at age 14 years. Neonatal data and outcome results of earlier assessments from early and late responders were compared to those of non-responders by univariate and nominal (polytomous logistic) regression analysis. SUBJECTS: There were 723 (76%) early responders, 130 (14%) late responders and 109 (11%) non-responders. RESULTS: We found significantly more non-Dutch origin and more disabilities and school problems at age 10 years in late- and especially in non-responders. At age 14 years, the health utility index was significantly lower in late responders compared to early responders. School outcome did not show difference in relation to the response groups. CONCLUSION: The results suggest that the incidence of adverse outcome in very preterm infants is underestimated when follow-up is incomplete and hence response rate is not a negligible problem in the assessment of late outcome. Therefore, follow-up studies should include a drop-out analysis to enable comparison to other studies.

Trends in hospital admissions among children aged 0-19 years with type I diabetes in The Netherlands.

OBJECTIVE: To determine the number and duration of hospital admissions due to diabetes in children aged 0-19 years between 1980-1991. RESEARCH DESIGN AND METHODS: Secondary analysis of data collected by the SIG Health Care Information was based on the 9th revision of the International Classification of Diseases. The subjects were all children in The Netherlands, aged 0-19 years. The main outcome measures were number and duration of hospital admissions due to type I diabetes (ICD 9 code 250.0-250.9). RESULTS: The hospital admission rate due to diabetes decreased > 30%. This decrease was statistically significant in all age subgroups. The total number of days in hospital due to diabetes decreased dramatically: from 24,961 in 1980 to 11,305 in 1991. The average duration of hospital stay length due to diabetes decreased as well from 14.5 days in 1980 to 11.9 days in 1991. CONCLUSIONS: The hospital admission rate and the length of hospital stay for diabetes in children aged 0-19 years have decreased, in spite of an increasing incidence. The hospital admission rate may decrease still further if more children with newly diagnosed diabetes can be adequately managed by team management at home in the initial phase.

Increasing incidence of type I diabetes in The Netherlands. The second nationwide study among children under 20 years of age.

OBJECTIVE: A nationwide retrospective study was conducted to assess the incidence of type I diabetes in The Netherlands among children < 20 years of age in 1988-1990. The first study with a similar design covered 1978-1980. RESEARCH DESIGN AND METHODS: The capture-recapture census method was chosen for analysis of the data. A questionnaire was sent to all Dutch pediatricians and internists, and for the ascertainment, a similar questionnaire was sent out separately to members of the Dutch Diabetes Association, which is the national patient association. RESULTS: The average achieved ascertainment rate was 81%. The ascertainment-adjusted annual incidence was 13.2/100,000 for 0- to 19-year-old children, indicating an increase of 23% compared with the 1978-1980 survey; for 0- to 14-year-olds, the increase amounted to 17%. CONCLUSIONS: This study suggests a sustained increase of type I diabetes in The Netherlands because the cumulative incidence studied previously in the 1960-1970 birth cohorts of male army conscripts 18 years of age was also found to rise. In contrast to Northern European countries, an increase in incidence for the age category 0-4 years could not be found.

Profiling the preterm or VLBW born adolescent; implications of the Dutch POPS cohort follow-up studies.

In 1983, data of a unique nationwide cohort of 1338 very preterm (<32 weeks of gestation) or VLBW (birth weight<1500g) infants in the Netherlands was collected and followed at several ages until they reached the age of 19 years. At 19 years of age a more extensive follow-up study was done, including questionnaires, tests on a computer and a full physical exam. These studies provide insight into how Dutch adolescents at 19 years of age, who were born very preterm or with a very low birth weight (VLBW), reach adulthood. At 19 years, 705 POPS participants participated (74% of 959 still alive). Outcome measures at 19 years included: physical outcomes (e.g. blood pressure), cognition, behavior, quality of life, and impact of handicaps. The POPS participants showed more impairments on most outcome measures at various ages, compared to norm data. Major handicaps remained stable as the children grew older, but minor handicaps and disabilities increased. At 19 years of age, only half (47.1%) of the survivors had no disabilities and no minor or major handicaps. Especially those born small for gestational age (SGA) seem most vulnerable. These long-term results help to support preterm and SGA born children and adolescents in reaching independent adulthood, and stress the need for long term follow-up studies and to promote prevention of disabilities and of preterm birth itself.

Mortality in very preterm and very low birth weight infants according to place of birth and level of care: results of a national collaborative survey of preterm and very low birth weight infants in The Netherlands.

As part of a collaborative project in the Netherlands in 1983, for which data were collected on 1,338 newborn infants (less than 32 weeks' gestation and/or less than 1,500 g birth weight), all infants were assigned to one of three levels of care according to hospital of birth. Considerable centralization was achieved by antenatal and neonatal transport. Although the uncorrected mortality rates were similar, the mortality odds (adjusted for four and 22 potential confounding perinatal factors, respectively) were significantly higher in level 1 and level 2 hospitals compared with level 3 hospitals (tertiary perinatal care centers). By extending the facilities for full perinatal intensive care in level 3 centers and thus providing optimal care for all such infants, the overall mortality rate is expected to decrease further.

Hyperbilirubinemia in preterm infants and neurodevelopmental outcome at 2 years of age: results of a national collaborative survey.

As part of a prospective national survey of preterm and small for gestational age infants in the Netherlands, the relationship between maximal serum total bilirubin concentration in the neonatal period and neurodevelopmental outcome at the corrected age of 2 years was studied. Initially, 1,338 infants with a gestational age of less than 32 completed weeks and/or a birth weight of less than 1,500 g were enrolled in the study; 146 were subsequently excluded because of congenital malformations and 361 died during the study period. At the corrected age of 2 years, 831 children were available for follow-up. Children with minor and major handicaps had significantly greater maximal serum total bilirubin concentrations than children with a normal neurodevelopmental outcome (P = .02). A consistent increase in prevalence of handicaps was found for each 50-mumol/L (2.9 mg/dL) increase of maximal serum total bilirubin concentration. The handicaps consisted mainly of cerebral palsy. Logistic regression analysis involving seven suspected confounding factors (gestational age, birth weight, seizures, intracranial hemorrhage, respiratory distress syndrome, ventriculomegaly, and bronchopulmonary dysplasia) revealed that the odds ratio was 1.3. This indicates that, on a multiplicative scale, the risk of a handicap increased by 30% for each 50-mumol/L (2.9 mg/dL) increase of maximal serum total bilirubin concentration (P = .02). Further analysis treated bilirubin as a categorized exposure. A striking systematic increase was found, suggesting a causal relationship between maximal serum total bilirubin concentration and neurodevelopmental outcome.

Hyperbilirubinemia in low birth weight infants and outcome at 5 years of age.

The collaborative national survey on morbidity and mortality in preterm and small for gestational age infants in the Netherlands enrolled initially 1338 infants born in 1983. The relationship between maximal serum total bilirubin concentration in the neonatal period and neurodevelopmental outcome in the survivors of this cohort was studied. This relationship at the corrected age of 2 years was previously reported. A dose-response relationship between maximal serum total bilirubin concentration and risk of adverse outcome was observed in the 831 surviving children. The present study reassessed the relationship at the age of 5 years in 814 children. There was no significant difference in mean maximal serum total bilirubin concentration between the children with and without a handicap. This was confirmed by logistic regression analysis. After correction for seven suspected confounding factors (gestational age, birth weight, intracranial hemorrhage, ventriculomegaly, seizures, bronchopulmonary dysplasia, and socioeconomic status) the estimated odds ratio was 1.2 (confidence interval 0.89, 1.43) per 50 mumol/L increase of total bilirubin. However, in this analysis an interaction between bilirubin and intracranial hemorrhage was observed. Therefore, the cohort was divided into two groups according to the absence or presence of an intracranial hemorrhage. Logistic regression analysis including four suspected confounding factors (gestational age, ventriculomegaly, seizures, and socioeconomic status) was then again applied. In children who had suffered from an intracranial hemorrhage in the neonatal period the estimated odds ratio was 1.84 (confidence interval 1.08, 3.15) per 50 mumol/L increase of bilirubin. Similar results were obtained treating bilirubin as a categorized exposure. The odds ratio in children without a hemorrhage was 1.05 (confidence interval 0.80, 1.38), probably because of the small number of surviving handicapped children.

Sex difference in disability and handicap at five years of age in children born at very short gestation.

OBJECTIVE: The objective of this study was to examine the relationship between sex and disabilities or handicaps at 5 years of age in infants born at less than 32 weeks gestation. DESIGN: From the nationwide collaborative survey starting in 1983, including perinatal data obtained during routine perinatal care and follow-up assessments by the attending pediatricians, data from 1008 infants fulfilling the criteria were used. At age 5 years, a detailed assessment was performed by three specially trained pediatricians in 96% surviving infants (n = 648), of which 345 were boys. Each child was categorized as disabled or handicapped, using World Health Organization definitions. RESULTS: The prevalence of handicaps was three times greater in boys than in girls (21% vs 7%, odds ratio 3.2). Adjustment for gestational age and birth weight (logistic regression analysis) did not change this (odds ratio 3.5). Further adjustment by including perinatal variables such as idiopathic respiratory distress syndrome did not alter the odds ratios. The male excess in handicaps was not related to lower mortality, and therefore was not a mere consequence of a higher survival rate. The excess in handicaps was found in all assessed areas. CONCLUSIONS: Infants' sex seems to be an important determinant of handicaps. The perinatal variables used in the present study do not explain the difference in handicaps. These findings emphasize the need to include the sex distribution of a study population more systematically in analyses in future studies concerning long-term outcome of very preterm birth or low birth weight.

Measuring health status using the Health Utilities Index: agreement between raters and between modalities of administration.

The aim of this study was to evaluate interrater and intermodality agreement in assessing health status using the Health Utilities Index. A random sample from a Dutch cohort of 14-year-old Very Low Birth Weight children and their parents were invited to participate in a face-to-face (n = 150) or telephone (n = 150) interview. All 300 participants were also sent a questionnaire by mail. Response rate was 68%. Interrater and intermodality agreement were high for the physical HUI3 attributes and poor for the psychological attributes. Children and parents reported more dysfunction in the psychological attributes when interviewed than when completing the mailed questionnaire. High agreement on the physical attributes may have resulted from the fact that hardly any dysfunction was reported in these attributes, and poor agreement in the psychological attributes may have been a result of the fact that in these attributes much more dysfunction was reported. In measuring children's health status using the HUI3, the results and their interpretation vary with the source of information and the modality of administration. For maximum comparability between studies, written self-report questionnaires seem the preferred option.

Differential misclassification of alcohol and cigarette consumption by pregnancy outcome.

BACKGROUND: The validity of the results of studies using retrospectively collected information on exposures is often criticized, because cases may report differently from controls even if their true exposure status is the same. This study was performed to quantify the extent to which this effect (differential misclassification) may occur for alcohol and cigarette consumption by pregnancy outcome. METHODS: Prospective as well as retrospective information on alcohol and cigarette consumption was collected for 2806 mothers resident in all 12 provinces of the Netherlands, who gave birth between 1978 and 1979. Changes in mean reported consumption and changes from user to non-user based on retrospective and prospective information were compared for cases and controls. This was done by calculating absolute differences (retrospective minus prospective) in reported consumption and by calculating 'misclassification odds ratios'. Further, conventional odds ratios based on retrospective information were compared with those based on prospective information. Outcome measures were stillbirth, small for gestational age (SGA), congenital malformations, preterm birth and low birthweight. RESULTS: The only statistically significant result was found for smoking and SGA. Mothers with an SGA child retrospectively reported a higher number of cigarettes smoked than they had prospectively, more so than mothers of a control child. However, the odds ratios of the relation between SGA and smoking based on prospective and retrospective information, respectively, were virtually the same. CONCLUSIONS: Our results suggest that information bias is unlikely to have a large influence on effect estimates in studies using retrospective information on alcohol and cigarette consumption.

Identification and management of psychosocial problems by preventive child health care.

OBJECTIVES: To assess the degree to which physicians and nurses working in preventive child health care (child health professionals [CHPs]) identify and manage psychosocial problems in children, and to determine its association with parent-reported behavioral and emotional problems, sociodemographic factors, and general and mental health history of children. DESIGN: The CHPs examined the child and interviewed parents and child during their routine health assessments. The parents completed the Child Behavior Checklist. SETTING: Nineteen child health care services across the Netherlands, serving nearly all school-aged children routinely. SUBJECTS: Of 4970 children aged 5 through 15 years, eligible for a routine health assessment, 4480 (90.1%) participated. MAIN OUTCOME MEASURES: Identification and management of psychosocial problems by CHPs. RESULTS: In 25% of all children, CHPs identified 1 or more psychosocial problems. One in 5 identified children were referred for further diagnosis and treatment. Identification of psychosocial problems and subsequent referral were 6 times more likely in children with serious parent-reported problem behavior according to the Child Behavior Checklist total problem score (8% of total sample). However, CHPs identified no psychosocial problems in 43% of these children and therefore undertook no action. Other child factors associated with CHPs' identification and referral were past treatment for psychosocial problems, life events, and academic problems. After adjustment for these, sociodemographic characteristics did not predict referral. CONCLUSIONS: The CHPs identify psychosocial problems in school-aged children frequently and undertake actions for most of them. Screening for psychosocial problems may be a promising option to reduce these problems, but accurate identification should be enhanced.

Five-year outcome of preterm and very low birth weight infants: a comparison between maternal and neonatal transport.

OBJECTIVE: To determine the 5-year outcome of very low birth weight infants referred to tertiary perinatal centers. METHODS: This study was part of a Dutch national collaborative survey of 1338 newborn infants younger than 32 weeks' gestation and/or with a birth weight of less than 1500 g born in 1983. Comparisons were made between maternal transport to university hospital perinatal centers versus delivery in local hospitals, and between neonatal transport to these centers versus treatment in local hospitals. For the 252 survivors meeting the entry criteria for this part of the study, adverse outcome at 5 years of age was evaluated by logistic regression analysis, including 26 perinatal risk factors as confounding variables. Outcome variables were disabilities and handicaps at 5 years as defined by the World Health Organization. RESULTS: There were no differences in handicaps and disabilities between infants born after maternal transport and those born in local hospitals. Handicaps and disabilities in neonates transported versus those treated in local hospitals were also not statistically different despite selection bias. CONCLUSIONS: The previously reported decrease in neonatal mortality risk after maternal transfer is not accompanied by an increased risk of adverse outcome for the survivors. In threatening very preterm delivery, maternal transport to a tertiary center is recommended.

School absence and treatment in school children with respiratory symptoms in The Netherlands: data from the Child Health Monitoring System.

STUDY OBJECTIVE: To assess the prevalence of respiratory problems, and the relation of these problems with school attendance, medicine use, and medical treatment. DESIGN: The Child Health Monitoring System. SETTING: Nineteen public health services across the Netherlands. PARTICIPANTS: 5186 school children aged 4-15 years, who were eligible for a routine health assessment in the 1991/1992 school year. MAIN RESULTS: Respiratory symptoms were present in 12% of the children. Recent symptoms suggestive of asthma (wheezing or episodes of shortness of breath with wheezing in the past 12 months, or chronic cough, or a combination of these) were reported for 8%. These symptoms were most frequent in the younger children, and in children at school in towns with less than 20,000 inhabitants. Of the children with recent symptoms suggestive of asthma, 37% reported school absence for at least one week during the past 12 months, compared with 16% in children without respiratory symptoms. School absence because of respiratory illness was reported for 22%, and medicine use for respiratory problems for 38% of the children with recent symptoms suggestive of asthma. Of these children, 21% were receiving medical treatment, compared with 15% of the asymptomatic children. CONCLUSIONS: Respiratory symptoms are a common health problem in children, and they are an important cause of school absence and medicine use. However, the percentage of children receiving medical treatment seemed quite low, indicating that proper diagnosis and treatment are probably still a problem.

Prevalence of self-reported food hypersensitivity among school children in The Netherlands.

OBJECTIVES: To provide national figures on the prevalence of self-reported food hypersensitivity (S-FH), and the association with socio-demographic variables and some health indicators in schoolchildren in The Netherlands. DESIGN: As part of the Child Health Monitoring System, data were collected from 4450 children, who were invited for a routine health assessment (response 97%). A questionnaire on food hypersensitivity was completed by the parents of the children in primary school and by the children in secondary school themselves. The measurements on health status were taken by the school physician or nurse during the school health assessment. SUBJECTS: Children aged 4-15 y in The Netherlands in three groups in primary school, and in the second year of secondary school. RESULTS: The prevalence of S-FH was 7.2%. Food additives and chocolate were most frequently avoided. Of the children with S-FH, 40% avoided food exclusively either on their own accord or on advice of relatives. School absence due to illness, use of medication, and medical treatment were more prevalent in children with S-FH, and their health status was more often considered moderate or poor by the school physician or nurse. CONCLUSION: Seven percent of school-aged children avoid certain types of food or ingredients because of S-FH. The prevalence of food allergy or food intolerance is probably lower, since many children with S-FH had not undergone any diagnostic tests. To prevent unnecessary food restriction, more information for parents is needed about the possible effects of food restriction on the health of their children, and they should be encouraged to seek further diagnosis.

Comparison of mortality and rates of cerebral palsy in two populations of very low birthweight infants.

Comparisons of mortality and rates of cerebral palsy in different populations can be confusing. This is illustrated by comparing two populations of very low birthweight infants born in the 1980s, one from the Netherlands, the other from the UK (Oxford region). Although a number of biases were controlled for while comparing two large geographically defined populations, by assessing the survivors at similar ages and describing their health status in a standard way, some problems in interpretation of outcome remained. Differences in registration practice of live births at early gestational ages, as well as differences in withholding or withdrawing treatment, which occurred in about half of the cases of neonatal death in the Netherlands and in about one third of those in the Oxford region, may have influenced the incidence of registered live births, neonatal mortality, and the rate of cerebral palsy.

Looking back in time: outcome of a national cohort of very preterm infants born in The Netherlands in 1983.

In 1983, Dutch pediatricians collaborated on a national level and collected perinatal data on 1338 liveborn infants with a gestational age <32 weeks and/or a birthweight <1500 g (project on preterm and small for gestational age infants, POPS). Their outcome was assessed at 2 years of age by their pediatricians, at 5 years by a team of investigators, and at 9-14 years by questionnaires completed by parents, teachers, and children themselves. The overall picture that emerges from this 14-year follow-up is that a low percentage of these very preterm infants (10%) has a severe disability or handicap at school age. Although 90% of the children are without severe disabilities at school age, many of them meet serious difficulties in everyday life and the burden of mild developmental abnormalities, behavioral and learning disorders increases with age. In adolescents, it is likely that as many as 40% of the survivors will not be able to become fully independent adults. Abnormalities found during early, standardized clinical neurological examination are highly predictive for these later problems.

Prenatal risk factors for cot death in very preterm and small for gestational age infants.

In a nationwide prospective survey on very preterm and very-low-birthweight infants in The Netherlands, the incidence of cot death in infants discharged alive was 15%. The postnatal age at death in these infants did not differ significantly from age at death in other cot death infants. Using a case-control design, possible risk factors associated with cot death were identified: lower maternal age at first pregnancy; maternal smoking during pregnancy; hypothermia of the infant immediately after birth; decreased number of white blood cells and thrombocytes in the infant on the first day of life. Intrauterine hypoxia is hypothesized as the entity common to these factors.