Obstetrical and neonatal risk factors in very low birth weight infants related to their neurological development

Outcome of very-low-birth-weight (< 1,500 grams) infants born to mothers with diabetes

Premature delivery is common in pregnancies complicated by maternal diabetes. However, the outcome of very-low-birth-weight infants (VLBWI) born to mothers with diabetes is not known. Employing a matched double-cohort design, we investigated the influence of maternal diabetes on the outcome of VLBWI born in Winnipeg from 1988 to 1994. We compared mortality rates and early and late morbidity rates in VLBWI born to mothers with diabetes mellitus (DM) (cases, n = 43, 23 with gestational DM and 20 with pregestational DM) and without DM (controls, n = 539). Controls were matched for gestational age (GA), sex, and the year of birth. All subjects were enrolled in the Newborn Follow-Up Program. Relative risks and 95% confidence limits were calculated for each variable and Chi 2 analysis, Student t-test, and Mann-Whitney test were used as appropriate for analysis. Diabetes mellitus control was assessed by conventional criteria. There were no differences between cases and controls in mode of delivery, birth weight (mean +/- SD, 1,160 +/- 25 g vs 1,110 +/- 26 g), GA (29 +/- 2.8 wk vs 29 +/- 2.4 wk), smallness for gestational age (35% vs 30%), head circumference (26.5 +/- 1.9 vs 26.2 +/- 2.2 cm), length (38.8 +/- 2.8 vs 37.5 +/- 3.7 cm), Apgar score < 4 at 1 min (42% vs 40%) and < 7 at 5 min (37% vs 42%). Incidence of hyaline membrane disease (60% vs 71%), bronchopulmonary dysplasia (33% vs 31%), patent ductus arteriosus (30% vs 43%), necrotizing enterocolitis (12% vs 12%), sepsis (23% vs 25%), acute renal failure (9% vs 10%), intraventricular hemorrhage--all grades (74% vs 64%), retinopathy of prematurity--all stages (30% vs 26%), median days on ventilator (4 vs 4 days), and median days on supplemental oxygen (46 vs 42 days) were similar in both groups (p = NS, 95% confidence limits included 1 for all of these variables). There was no significant difference in mortality (21% vs 15%) or the incidence of major congenital anomalies. Weight, head circumference, and length at 6, 12, and 18 months were similar in both groups. There were no group differences in developmental quotients, prevalence of neurodevelopmental impairments, respiratory morbidity, or number of hospitalizations up to the last follow-up (18 months). Our data suggest that with contemporary perinatal care there is no significant increase in mortality rates or early and late morbidity rates between VLBWI born to mothers with DM and VLBWI of nondiabetic mothers. It seems that with reasonable diabetic control, prematurity rather than the diabetic state determines the neonatal outcome, and this knowledge can be useful in parental counselling.

Bilateral spastic cerebral palsy--a collaborative study between southwest Germany and western Sweden. III: Aetiology

In this third report from the collaborative study of children with bilateral spastic cerebral palsy born between 1975 and 1986, aetiology was analysed. Evidence for a prenatal aetiology increased with gestational age, whereas evidence for a peri-/neonatal aetiology decreased. The largest subgroup, the leg-dominated subtype, showed the same distribution of aetiology as the total group. A prenatal aetiology was found mainly among term and moderately preterm children with a four-limb-dominated subtype; a peri-/neonatal aetiology among very preterm children with a three- or four-limb-dominated subtype or among term children with a dyskinetic-spastic subtype. The findings support the hypothesis generated from the authors' epidemiological results of a peri-/neonatal aetiology being predominant among preterm, and a prenatal aetiology among term, children with bilateral spastic cerebral palsy.

Development of very low birth weight infants: a regional study of 371 survivors

We re-examined 371 infants with birth weights less than 1501 g at a corrected age of 18-20 months. This sample amounted to 91% of such infants admitted to one of the six neonatal intensive care units in Hamburg between July 1983 and 1986. The neurological examination and a developmental evaluation using the Griffith Developmental Scale revealed higher rates of abnormalities than in most other studies. Fifty-five children (14.8%) suffered from cerebral palsy, classified in 45 as spastic diplegia, in 5 as spastic tetraplegia, in 1 as spastic hemiplegia and in 4 as dystonia. Of the children, 41 (11%) showed minor neurological deviations (hyperactivity, clumsiness, intention tremor). The development of 30 children (8%) without neurological abnormalities was moderately retarded (DQ 80-89, corrected for gestational age [GA]). Nineteen children (5%) were severely retarded (DQ less than 80, corrected for GA) and four children (1.5%) were blind due to retrolental fibroplasia. An isolated delay of speech development was found in 5 children. Seventy children (18.9%) had a major and 87 children (23.5%) a minor handicap.

Hemiplegic cerebral palsy. Aetiology and outcome

Hemiplegic cerebral palsy (CP) was studied in a retrospective population-based series of 169 cases from the South-western Swedish health care region covering the birth years 1969-78. The purpose was to analyse the prevalence, aetiology and neuro-developmental outcome in children born preterm and at term, and to correlate pathogenetic periods, aetiological factors and clinical parameters to neuroradiology. The prevalence at the ages 6-15 years was 0.66 per 1000. Postnatally acquired hemiplegia, mainly postinfectious, iatrogenic or posttraumatic, constituted 11%. Among term children with congenital hemiplegia (pre and perinatally derived) the aetiology was considered prenatal, mainly circulatory brain lesions and maldevelopments, in 42%, combined pre and perinatal in 9%, perinatal (cerebral haemorrhage, hypoxia) in 16% and untraceable in 34%. The corresponding distribution among preterm children was 29%, 47%, 25% and 6%, respectively. The rate of preterm birth among congenital cases was 24%. Birth asphyxia was shown to be a poor indicator of pathogenetic period, whereas a cascade of postpartum complications suggested perinatal brain damage. Clinical follow-up of 152 children revealed that 50% had mild, 31% moderate and 19% severe motor dysfunction. Stereognostic sense was impaired in 44% of the children (astereognosia in 20%). Additional impairments (mental retardation, epilepsy, impaired vision, hearing and speech, severe behavioural/perceptual problems) were present in 42%. Term children with congenital hemiplegia tended to be more severely affected than preterm children. The resulting total handicap was considered mild in 40%, moderate in 44% and severe in 16%. The prevalence of severe total handicap was highest among postnatal cases. Computerised tomography (CT), performed in 109 congenital cases, was normal in 26%, showed unilateral ventricular enlargement in 36% and revealed cortical/subcortical cavities in 20%. In the remaining 18% CT findings were classified as "other". With the classification so far used, correlations between CT findings and aetiologies were unsatisfactory and disappointing. In contrast, CT findings showed a strong correlation with clinical degree of severity and magnitude of associated handicap. As a rule, normal CT implied mild disability and unilateral ventricular enlargement moderate, whereas cortical/subcortical cavities were frequently associated with severe handicap, including mental retardation and epilepsy.

Improved outcome in very low birth weight infants from 1977 to 1983

Changes of mortality and neurological morbidity in 351 very low birth-weight infants cared for in the neonatal intensive care unit of the Children's Hospital Tübingen during the years 1977 to 1983 are reported. The main finding was a survival rate increasing from 69.5% in 1977-79 to 76.6% in 1982-83 and a coinciding frequency of severe neurological sequelae decreasing from 9.2%-3.7%. The incidence of minor neurodevelopmental problems remained unchanged. However, mortality after discharge was found to be increased during the period observed. In conclusion, the intensification of neonatal intensive care in our hospital did not only reduce mortality but also the rate of severe neurological sequelae, thus not only survival rate but also the quality of survival could be improved.