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© International Epidemiological Association 1997 Printed in Great Britain
EDEN (Etude du Developpement des Nouveau-nés— Study of the Development of Newborns) is an ongoing prospective study which will determine the incidence and prevalence of chronic conditions from all causes at 18 months and 4 years of age in a geographically de-fined region (Canton of Vaud, Switzerland). As treat-ment of fragile newborns in intensive care units improves their chance of survival, concerns are being raised by professionals and parents about the quality of life for those who survive into childhood and adulthood.
The infant mortality rate in Switzerland is one of the lowest in the world (5.1 per 1000),1 but as in most industrialized countries, controversies still hold about the trends in the incidence of disability.2,3Differences in the definition of study populations and in the meas-urement of outcomes make comparisons between popu-lations and periods difficult.4,5 Although the need for population-based follow-up studies has regularly been emphasized in the literature, few have been conducted6–9 because the recruitment and follow-up efforts are much greater than for hospital cohorts. Those studies that do exist focus almost exclusively on very-low-birthweight infants, usually survivors of one NICU, and on neuro-developmental disability.10,11
This paper reports on the recruitment and initial results of a cohort of newborns at increased risk of de-veloping a chronic condition, describing how caveats encountered in previous studies have been avoided. * Health Services Unit, Institute of Social and Preventive Medicine,
University of Lausanne, Switzerland.
** Neonatal and Developmental Units, Department of Pediatrics, CHUV, Lausanne, Switzerland.
†Pediatrics Association of Canton of Vaud, Obstetrics and Gynecology Association of Canton of Vaud, residents, nurses and midwives of the pediatrics and obstetrics departments of the participating hospitals.
Enrolment of a Population-Based
Cohort of Newborns at Higher Risk
of Developing a Chronic Condition:
the EDEN Study
V ADDOR,* B SANTOS-EGGIMANN,* C-L FAWER,** F PACCAUD,* A CALAME** AND THE EDEN STUDY GROUP†
Addor V (Health Services Unit, Institute of Social and Preventive Medicine, University of Lausanne, Switzerland), Santos-Eggimann B, Fawer C-L, Paccaud F, Calame A and the EDEN Study Group. Enrolment of a population-based cohort of newborns at higher risk of developing a chronic condition: the EDEN study. International Journal of Epidemiology 1997;
26: 340–348.
Objective. To describe the methods used at birth to recruit a population-based cohort of newborns of all birthweights at higher risk of having a chronic condition, and to present baseline results.
Methods. Screening of all newborns at hospital discharge for five non-exclusive criteria: (1) low birthweight (LBW), (2) con-genital anomalies or genetic disease, (3) specified conditions associated with a high probability of chronicity, (4) referral to a neonatal intensive care unit (NICU), (5) or defined social problems. Calculation of Hobel risk scores for children satis-fying ù1 criterion.
Subjects. All 6477 live births delivered in the 19 maternity hospitals of a geographically defined region (Vaud, Swit-zerland) to resident mothers in 1993–1994.
Results. Twelve per cent (n = 760) of newborns met ù1 criterion: 6.3% of all newborns had an LBW (criterion 1), 2.4% had a birth defect, 0.9% met criterion (3), 4.4% stayed in an NICU and 1.6% had serious social problems. Hobel prenatal score was high (ù10 points) for 41% of children with ù1 criterion, the intrapartum score for 87% and the neonatal score for 68%.
Conclusions. Most newborns identified by the above simple criteria also had elevated perinatal risks. The validity of the criteria will later be tested against the results of the examinations of children with ù1 criterion at 18 months and 4 years of age, but the assessment at birth already shows that normal birthweight (NBW) children, in agreement with previous studies, contribute half the children at high risk perinatally.
METHODS Setting
The EDEN study builds on a long-term follow-up programme of preterm (ø34 weeks) or ,1500 g infants which has been conducted by the Lausanne Develop-mental Unit since 1971.12All 18 maternity hospitals in the Canton of Vaud and an additional hospital in a border canton agreed to participate in the data collec-tion (Figure 1). The number of births attended at each facility ranged from 47 to 1800 in 1993–1994. The only tertiary hospital (1800 births) is located in Lausanne, the main city (20% of the 600 000 Vaud residents). This hospital is the referral centre for smaller facilities as well as for three neighbouring cantons.
Study Population
To optimize the follow-up rate, two border districts out of 19 were excluded because more than 35% of their residents received obstetric care outside Vaud in 1992,13 mostly because facilities were closer in a neighbouring canton. Excluded districts accounted for 4.9% of new-borns from Vaud residents (n = 377).14 Consequently,
1441 liveborn and six stillborn babies delivered in the participating hospitals were excluded from EDEN be-cause their mother lived in the excluded areas or out-side Vaud at the time of delivery (Figure 2). On the other hand, one maternity hospital located just beyond the border of Vaud (Figure 1, empty triangle) offers al-ternative methods of delivery and thus attracts a number
FIGURE1 EDEN study area
of women from Vaud who later obtain paediatric care in Vaud. Home births (5.5/1000 livebirths in Vaud in 199315) were not part of the data collection because hospitals have no information about them. However, nine infants born in the car or at home were included because they had at least one hospital contact on the first day of life. Between 1 October 1993 and 30 Sep-tember 1994, 6497 newborns of mothers living in the defined area were delivered in the participating hos-pitals, including 20 stillbirths. The EDEN cohort is thus made up of 6477 liveborn infants resulting from 6379 pregnancies (Figure 2).
Design
Predetermined non-exclusive criteria were used to identify a group of newborns at higher risk of having a chronic condition, who will be followed up. Two exam-inations are planned at 18 months and 4 years. These criteria were:
1. Birthweight ,2500 g.
2. Congenital birth defect or genetic disease using the definitions of the European Registration of Congenital Anomalies and Twins (EUROCAT).
3. Condition associated with a high probability of chronicity, with special or frequent health care needs compared to healthy peers.
4. Referral to NICU.
5. Serious social problems defined as mother’s age
,18, parent ex- or current- drug addict (including
alco-hol), psychiatric disease of a parent, or known family violence.
The rationale for these criteria was twofold. On the one hand, criteria 1 and 4 (in the absence of criteria 2 and 3) target newborns who do not have a lasting condition at discharge, but are known to experience more health problems in infancy or beyond, due to their prematurity and/or to transient neonatal morbidity. Criterion 5 stands along the line of studying chronic conditions from all
causes, taking into account environmental influences during childhood.16,17On the other hand, criteria 2 and 3 should detect any health problem appearing in the early neonatal period that might affect the child’s functional status, without trying to predict its exact duration. Cri-terion 3 was adapted to the situation at birth from Perrin et al.18 These authors favour a generic approach to
illness that emphasizes the consequences of the disease for the child, as opposed to the traditional disease-specific biomedical model.19They suggest that a condi-tion be considered chronic if it is expected to last more than 3 months, and the level of functional impairment or the use of medical care will be greater than that expected for a child of the same age. Criterion 3 covers maternally-transmitted infectious diseases, severe con-genital anomalies and consequences of prematurity such as retinopathy and broncho-dysplasia. This method based on health services utilization avoids long and fastidious lists of conditions that may or may not be-come chronic.19,20Such lists cannot be comprehensive and do not account for the consequences of the disease: a given condition may be benign or lead to serious im-pairment, depending on its severity as well as on the presence of associated illnesses. Because of the dif-ficulty of predicting the duration of the condition at birth, this aspect was not retained from Perrin’s definition.
Data Collection
Data collection was organized in several steps. First, information on the child’s sex, weight, length, multi-plicity and maternal age was extracted from an an-onymized copy of the birth certificate for all 7944 live and stillbirths that took place in the participating maternity hospitals, to check for the mother’s place of residence and make sure that no livebirth had been missed. Second, anonymous data were collected during the hospital stay for all livebirths to residents through a questionnaire to midwives asking for obstetric gesta-tional age (best estimate by ultrasound and last men-strual period), parity, gestity, substance abuse, smoking, parents’ occupation, nationality, marital status and Ap-gar score. Another form was completed by the pae-diatrician on the day of the infant’s discharge, including gestational age according to the Dubowitz assessment, general health of the newborn, and screening for inclu-sion criteria. Third, if the newborn met one or more criteria, paediatricians and obstetricians completed ex-tensive nominal questionnaires containing parent’s oral consent for participation, Hobel scores21and diagnoses. Overall, about 50 paediatricians, 70 obstetricians and 400 nurses and midwives participated in EDEN. To en-sure the completeness and accuracy of the data, four
liaison nurses co-ordinated and supervised the data col-lection in the hospitals, and tracked missing information. The full questionnaires, and the Hobel scores in par-ticular, are available for all LBW children, but only for normal birthweight (NBW) children who met at least one of criteria 2 to 5. The whole group of NBW babies can nevertheless be compared to others on the basis of the minimal data set collected for every birth.
Statistical Analysis
The whole set of births or only the subset of children meeting inclusion criteria were used depending on the goal of each analysis. χ2and two-tailed t-tests (both at
the 0.05 level) were performed to compare children who met ù1 criterion to those who did not. Categorical Hobel risk scores (prenatal, intrapartum and neonatal) were computed to describe perinatal risk at birth for babies with ù1 criterion, with ù10 points considered as high risk.
Definitions and Variables
The obstetric estimate was used for gestational age when equal to or above 37 weeks of gestation or if it was the only available measure, but the Dubowitz assessment was retained when the obstetric estimate was below 37 completed weeks. Hobel scores have been updated to take into account the advances in ob-stetrics since their conception in the 1970s (Appendix), staying as close to the original as possible. As sug-gested by Strobino et al. three items were removed from the neonatal score (feeding problems, failure to gain weight and jitteriness) because their measurement is subject to interpretation, their weight equals 1 and they did not change the results in these authors’ ana-lysis.22The treatment of missing items was as follows:
for 1–11% of the children (depending on the score), the sum of missing and ticked items was below the published cutoff of 10 points, so they could be categorized as low risk. When ticked items already added up to .10, chil-dren were classified in the high risk category. When ticked items were ,10, but missing items brought the score above the limit, the whole score was considered as missing.
RESULTS
Frequency of Inclusion Criteria and Description of the Population
About 12% of newborns met at least one inclusion criterion (n = 760, [Table 1]). Half of them were LBW (6.3% of all newborns), a fifth had congenital defects and about 1% had a condition associated with a high probability of chronicity. Most infants (71%) met a
single criterion and 25% met two criteria, most fre-quently LBW and referral to NICU. Expected differ-ences were observed between high-risk and low-risk children in terms of the baby’s characteristics (Table 2). Although the two groups were comparable for resid-ence and nationality, extreme maternal ages, smoking during pregnancy, father’s absence from household and low socioeconomic status were more common among children satisfying at least one criterion.
For 89% of babies, parents said they would par-ticipate in the subsequent assessments of their child’s health, but they refused for 9% of babies. The study could not be presented to the parents of the remain-ing 2% due to difficult family situations. They will be approached again by the paediatrician when the child is 18 months old.
Perinatal Risks as Assessed by Hobel Scores
All three Hobel scores were complete for 67% of children with ù1 criterion (n = 508). The risk status (,10 or ù10 points) could be determined for 92% (n = 699) of children with ù1 criterion for the prenatal score, for 96% (n = 732) of these children for the intrapartum score, and for 95% (n = 720) of these chil-dren for the neonatal score. No statistically significant differences were found between children with complete and incomplete neonatal score in weight, prematurity, criteria distribution, multiplicity, Apgar score at 5 min-utes or nationality.
Overall, only 41% (n = 287) of children with ù1 cri-terion could be considered at high prenatal risk accord-ing to the Hobel scoraccord-ing system (ù10 points) (Table 3).
TABLE1 Frequency of inclusion criteria (non-exclusive)
Criteria n % of % among
livebirths newborns
(n = 6477) with ù1
criterion
1. Birthweight ,2500 g 408 6.3 54
2. Birth defect or genetic 157 2.4 21 3. Condition with high
probability of chronicity 61 0.9 8
4. Referral to tertiary
intensive care unit 287 4.4 38
5. Social problems 105 1.6 14 One criterion 537 8.3 71 Two criteria 191 2.9 25 Three criteria 29 0.4 4 Four criteria 3 0.1 0 All newborns 760 11.7 100
This proportion was 52% among LBW infants and 28% among NBW ones. On the intrapartum variables, 87% (n = 633) of babies with ù1 criterion score ù10 points; this proportion was 100% for LBW babies and 69% for NBW babies. As to the neonatal section, 68% (n = 492) of babies with ù1 criterion scored ù10 points; this proportion was similar for LBW and NBW babies (66% and 72%).
Depending on the score (prenatal, intrapartum or neonatal), one third to one half of the babies with
ù1 criterion who were also considered high risk by the
Hobel system had a normal birthweight (ù2500 g). Since birthweight .2500 g is part of the intrapartum and the neonatal scores and was also an inclusion cri-terion, a second analysis was performed that subtracted the corresponding 5 or 10 points for LBW babies (see Appendix) in order to compare LBW to NBW babies on the basis of other items alone. The lower part of Table 3 indicates that although all LBW babies were still at high intrapartum risk and 61% still at high neo-natal risk according to the Hobel system, the proportion of NBW babies among high-risk babies increased from 36% to 42% for the intrapartum score, and from 49% to 54% for the neonatal score.
DISCUSSION
With LBW at 6.3% and prematurity at 5.9%, the study population was comparable to previously studied populations. The LBW rate was 6.5% in Great Britain in 1989,237.2% in the US in 199324and 4–5% in Nordic
countries.25EDEN preterm birth rate, the first available in a Swiss population, was similar to most European countries in 1991, higher than Japan (about 3.0%) but
TABLE2 Perinatal and demographic characteristics of newborns according to their inclusion status
High risk Low risk
(ù1 criterion) (no criterion)
n = 760 n = 5717
Mean birthweight + SD (g) 2654 (± 741) 3355 (± 417) Mean gestational age + SD
(completed weeks) 37.15 (± 2.89) 39.16 (± 1.26)
Premature (,37 weeks, %) 33.2 2.3
Small-for-gestational-age (%)a 27.8 4.0
Multiple births (%) 14.9 1.4
Apgars ,7 (%) 7.5 1.2
Early neonatal death (%), (n = 14) 1.8 0
Girls (%) 49.5 47.9 NSb
Type of maternity hospital (%)
Tertiary 44.6 22.4
Regional hospitals (levels I + II) 39.6 57.1 Private clinics (level I) 15.8 20.5 Maternal age (years, %)
,19 3.0 1.1
20–34 83.0 87.2
>35 14.0 11.7
Urban residence (vs. rural, %) 68.3 68.5 NS Low socioeconomic statusc(%) 23.0 18.8 Father not living in household (%) 7.5 2.4 Nationality
2 parents Swiss 53.5 56.3
2 parents foreigners 30.1 30.0
1 parent Swiss 16.4 13.7
Smoking during pregnancy (%) 30.6 17.7
aø10th percentile for Swiss singletons.
bNS = non significant; all other differences in this Table were statistically significant at the 5% level.
cBoth parents unemployed, refugees, father (or mother if missing) with unqualified occupation, one parent in apprenticeship.
TABLE3 High-risk status (Hobel scores >10 points) of children with >1 criterion by birthweight
Birthweight ,2500 g Birthweight ù2500 g All
(criterion 1, with or (criteria 2 to 5)
without other criteria)
n % (%a) n % (%a) n % (%a) Hobel scores ù10 Prenatal (n = 699) 199 69.3 (52.4) 88 30.7 (27.6) 287 100 (41.1) Intrapartum (n = 732) 408 64.5 (100) 225 35.5 (69.4) 633 100 (86.5) Neonatal (n = 720) 252 51.2 (65.5) 240 48.8 (71.6) 492 100 (68.3) Hobel scores ù10 (birthweight factor removed) Intrapartum (n = 638) 314 58.3 (100) 225 41.7 (69.4) 539 100 (84.5) Neonatal (n = 673) 205 46.1 (60.7) 240 53.9 (71.6) 445 100 (66.1)
much lower than the US (11.0%).24,25The prevalence of congenital anomalies (2.4%) was similar to the Euro-pean rate of 2.0% between 1980 and 199226as well as to the average international prevalence of 2.5% for structural births defects,27if one accounts for the fact that genetic diseases and chromosomal anomalies are not counted in usual registries, whereas they were in EDEN. The referral rate to NICU (4.4%) was within the range of 3–5% in European countries.28
The criteria were purposely broad enough to ensure that the majority of children who will develop a chronic condition in childhood were in the group that will be followed; case identification after the neonatal period, through paediatricians and specialists, is much more difficult at 18 months and 4 years of age. Therefore, the positive predictive value of the criteria is likely to be low. Nevertheless, can we say that newborns with
ù1 criterion were really at higher risk of developing a
chronic condition later in life? Simple bivariate comparisons show that as a group, they had indeed more general risk factors for morbidity than the rest of the cohort (Table 2). However, almost two thirds of them could be considered at low prenatal risk, despite the fact that many factors measured by the Hobel prenatal score are expected to affect the health of the infant, as reflected by criteria 1 to 4. The intrapartum and neonatal scores performed better, with respectively about 90% and 70% of children who met ù1 criterion scoring ù10.
One explanation for the overall low prenatal risk of children selected to be followed is that the Hobel pre-natal section was regarded as the most outdated by clinicians; it includes rare occurrences such as endo-crine or sickle cell diseases, but does not consider other important factors such as the prenatal diagnosis of mal-formations. Unfortunately, no other existing instrument can be applied to all newborns (whether they stayed in an NICU or not), incorporates all aspects of the peri-natal period (preperi-natal, intrapartum and neoperi-natal) and has been updated.29 The Hobel approach provides a
partially validated and comprehensive approach to summarizing perinatal events relevant to chronic conditions at 18 months and 4 years.
In the original unselected population in which the Hobel instrument was developed, a similar proportion of children (66%) had low prenatal scores and 64% of children had low intrapartum scores, and the correlation with the neonatal score (i.e. neonatal morbidity) was better for the intrapartum than for the prenatal score.21 An antepartum score adapted from Hobel by Wall et al. was only weakly correlated with the neonatal length of stay, but not with birthweight at all, while their intra-partum score was correlated with birthweight, Apgar
scores and length of stay.30Kelly et al. also found that only 15% of children transferred to an NICU had a Hobel prenatal score ù10, but transfer indications may have been broader than usual in this very low-risk popu-lation of in-practice and home deliveries.31In another study at two US centres, 66% and 74% women had low Hobel prenatal scores, but multiple pregnancies and women with serious medical conditions (part of the score) were excluded.32 Our results suggest that our high-risk newborns had in fact the same low prenatal risk as some general populations or even low-risk preg-nancies in the US, but a higher intrapartum risk. The unusually dense health care network of Vaud could explain the low prenatal score by a particularly efficient evaluation of obstetric risk. The higher proportion of babies with ù1 criterion born in the tertiary centre than in other hospitals indicated a successful regionalization effort that supports this interpretation (Table 2).
The most important limitation to the EDEN method-ology is the unavailability of Hobel scores for the whole cohort, which does not allow the calculation of their sensitivity and predictive value in relation to later chronic conditions. The major effort required for such data collection could not be asked from physicians, and there is no computerized system of medical data in Swiss hospitals from which information could be retrieved.
A less important point is that criterion 3 (condi-tion associated with a high probability of chronicity) is an unusual way to assess morbidity and may have been underused by paediatricians. However, children with such conditions have been included under other criteria and their health status will be reassessed at 18 months. It must be noted also that some inclusion criteria voluntarily overlap with the Hobel neonatal score, such as birth defects and LBW, to make sure that our defini-tion of risk at birth was sound by accepted standards. The next step will be to test the validity of the inclusion criteria used at birth against the results of subsequent assessments, i.e. comparing them to the presence or ab-sence of a chronic condition.
NBW children are major contributors to chronic con-ditions. They should be studied more systematically in order to get a clearer picture of chronic conditions from all causes and plan special education needs for the whole population. Finding early indicators of childhood morbidity that are valid for all newborns is of uttermost importance in public health.
ACKNOWLEDGEMENTS
The authors wish to acknowledge the dedication of M Becher, C Klay, G Lavanchy, V Pernet, liaison nurses,
who ensured the logistics of this study. We are also very grateful to A Clerc Bérod for her statistical help, to M-C Addor for checking the completeness of the birth defect registration with EUROCAT-Vaud, and to P Péteur for constructing the map. EDEN is supported by the Service des Hospices Cantonaux (Grant No. 4002).
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APPENDIX
Adaptation of the Hobel prenatal, intrapartum and neonatal scores for EDEN (modifications are in italic and original wording in parentheses)
I. Hobel prenatal score (51 items)
Weight Number of
children Cardiovascular and renal factors
10 Moderate to severe toxaemia 21
10 Chronic hypertension 11
10 Moderate to severe renal disease 7 10 Severe heart disease, class II-IV 3
5 History of eclampsia 3
5 History of pyelitis 7
5 Class 1 heart disease 2
5 Mild toxaemia 32 5 Acute pyelonephritis 4 1 History of cystitis 28 1 Acute cystitis 22 1 History of toxaemia 11 Metabolic factors
10 Gestational diabetes treated with
insulin (ù class A-II) 5 10 Previous endocrine disease (ablation) 3
5 Thyroid disease 2
5 Gestational diabetes treated with
diet (prediabetes A-I) 11 1 Family history of diabetes 11 Previous histories
10 Previous exchange transfusion for Rh 3
10 Previous stillbirth 7
10 Post-term .42 weeks 3
10 Previous premature infant 39
10 Previous neonatal death 11
5 Previous C-section 68 5 Habitual abortion .3 14 5 Infant .4500 g (.10 lbs) 4 5 Multiparity .5 1 5 Epilepsy 4 1 Fetal anomalies 16 Anatomic anomalies 10 Uterine malformation 12 10 Incompetent cervix 12
10 Abnormal fetal position 32
10 Polyhydramnios 6
5 Small pelvis 24
Miscellaneous
10 Abnormal cervical pathology 9
10 Multiple pregnancy 119
10 Sickle cell disease 0
5 Age ù35 or ø15 107
5 Viral disease 17
5 Rh sensitization only 10
5 Positive serology, including HIV 21
5 Severe anaemia (Hb ,9 g) 2
5 Excessive use of drugs 18
5 History of tuberculosis or PPD
ù10 mm 1
5 Weight ,48 kg or .90 kg
(,100 lbs or .200 lbs) 45
5 Pulmonary disease 4
5 Severe flu syndrome 4
5 Vaginal spotting 16
1 Mild anaemia (Hb 9–10.9 g) 27 1 Smoking yes/no (ù1 pack/day)a 213
1 Alcohol (moderate) 4
1 Emotional problem 42
aIt may be understood that the original score asked for
smoking ù1 pack during the whole pregnancy. Because the number of cigarettes was missing more often than the yes/no answer, we used the latter to compute this item, ‘yes’ corresponding to smoking during all tri-mesters of pregnancy. This allowed us to compute the Hobel score for 435 children, who would otherwise have been excluded from the analyses.
II. Hobel intrapartum score (40 items)
Weight Number of
children Maternal factors
10 Moderate to severe toxaemia 26
10 Hydramnios/oligamnios 92
10 Amniotis 18
10 Uterine rupture 6
5 Mild toxaemia 47
5 Premature rupture of membranes
.12 hours 156
5 Primary dysfunctional labour 40 5 Secondary arrest of dilation 32 5 Analgesics/narcotics (Demerol .300 mg) 79
5 MgSO4 .25 g 9
5 Labour .12 hours (.20) 7
5 Second stage .2.5 hours 28
5 Clinical small pelvis 33
5 Medical induction 148
5 Precipitous labour ,3 hours 188
5 Primary C-section 212
5 Repeat C-section 85
1 Elective induction 31
1 Prolonged latent phase 7
1 Uterine tetany 3
Placental factors
10 Placenta praevia 11
10 Abruptio placenta 31
10 Post-term .42 weeks 2
10 Meconium-stained amniotic fluid (dark) 50 5 Meconium-stained amniotic fluid (light) 44
1 Marginal separation 19
Fetal factors
10 Abnormal presentation 65
10 Multiple pregnancy 119
10 Fetal bradycardia .30 minutes 24 10 Breech delivery total extraction 10
10 Prolapsed cord 7
10 Fetal weight ,2500 g 408
10 Fetal acidosis pH ø7.25 125
10 Fetal tachycardia .30 minutes 10 5 Operative forceps or vacuum extraction 48 5 Breech delivery spontaneous or assisted 7
5 General anaesthesia 86
1 Outlet forceps 31
1 Shoulder dystocia 7
III. Hobel neonatal (32 items)
Weight Number of children General factors 10 ,2000 g 110 10 Apgar at 5 minutes ,5 18 10 Resuscitation at birth 126 10 Fetal anomalies 114 5 Dysmaturity 39 5 2000–2499 g (2000–2500 g) 298 5 Apgar at 1 minute ,5 81 1 Multiple birth 113a Respiratory factors
10 Respiratory Distress Syndrome 161 10 Meconium aspiration syndrome 11
10 Congenital pneumonia 29
10 Anomalies of respiratory system 5
10 Apnoea 28
10 Other respiratory distress 7
5 Transient tachypnoea 55
Metabolic disorders
10 Hypoglycaemia 65
10 Hypoglycaemia 12
5 Hypo- or hyper- magnesemia 0
5 Hypoparathyroidism 0
Cardiac factors
10 (Major) cyanogen cardiac anomalies
(requiring immediate catheterization) 6 10 Cardiac heart failure without malformation 0
5 Persistent cyanosis 6
5 Non-cyanogen cardiac anomalies (not requiring immediate catheterization) 57
5 Murmur 85 Haematologic problems 10 Hyperbilirubinaemia 147 10 Haemorrhagic diathesis 0 10 Chromosomal anomalies 4 10 Sepsis 23 5 Anaemia 57
Central Nervous System (=CNS)
10 CNS depression .24 hours 7
10 Seizures 6
5 CNS depression ,24 hours 10
aThere were more multiple births in the prenatal and
intrapartum scores than in the neonatal score because of the loss of one fetus before delivery in some pregnancies.
