Prematurity Research Disproves the Theory that Preemies Catch Up By Age Three - part 2
The common belief that preemies catch up by age three is not supported by research.
By Patti Wrape
26. A nine year follow up of 116 children born in 1971 to 1974 with a birthweight of 1,500 grams or less found that 59 had died and 7 had extreme handicaps or blindness. The low birthweight children without extreme handicaps were found to have impaired motor function, speech defects and impaired school achievements more often than the controls. Nine Year Follow Up of Infants Weighing 1,500 grams or Less at Birth. Michelsson K, Lindahl E, Parre M, Helenius M. Acta Paediatr Scand. November 1984; 73 (6): 835-41.
27. Thirty five of 45 long term survivors with birth weights of 1,000 grams or less whor were cared for in the University of Washington, Seattle, Neonatal Intensive Care Unit, from 1960 to 1972 were examined at an average age of 10 ½ years. Twenty eight percent had one or more major neurological or sensory handicap, 64% have been or are presently in a special education program. Only 28% are currently rated by their teachers to be achieving at or above grade level. Arithmetic reasoning, mathematics achievement and reading comprehension were specific weaknesses. Fine and gross motor skills were impaired. Perceptual skills were impaired to a lesser degree. School Performance of Children with Birth Weights of 1,000 Grams or Less. Nickel RE, Bennett FC, Lamson FN. Am J Dis Child, Feb 1982; 136 (2): 105-10.
28. This study examined the relationship between very low birthweight children and possible developmental delay in the absence of frank developmental disability. Subjects were asymptomatic for disabling conditions but apparently well, very low birthweight, children were consistently at greater risk for both moderate and severe measures of delay across four functional areas. Relation Between Very Low Birth Weight and Developmental Delay Among Preschool Children Without Disabilities. Schendel DE, Stockbauer JW, Hoffman HJ, Herman AA, Berg CJ, Schramm WF. Developmental Disabilites Branch, Centers for Disease Control and Prevention, Chamblee GA, Usaam J. Epidemiol, November 1, 1997; 146 (9): 740-9.
29. At the adjusted age of 5 years the development of 106 children born 5 or more weeks before term was compared with the development of 103 children born at term. No children with cerebral palsy were included and the groups were matched in terms of sex, age, birthplace, race and residential location. The results indicated a significant difference between the two groups including preterm children having small involuntary hand movements, less competent gross motor ability, poorer verbal performance and more variability in behavior postural response and balance. A higher than average incidence of minor motor, speech, behavior and learning problems in early school years is probable. Language and Motor Development in Pre Term Children: Some Questions. Le Normand MT, Vaivre-Douret L, Delfosse MJ. INSERM, Hospital de La Salpetriere, Paris, France. Child Care Health Dev, March 1995; 21 92) 119-33.
30. A study conducted in a Southern Swedish population compared extremely preterm children to a control group of full term children at age 10. Health, cognitive development, school achievement and behavior were evaluated. Thirty eight percent of the extremely preterm children performed below grade level at school. Thirty two percent had general behavioral problems and 20% had attention deficit hyperactivity disorder compared with 10% and 8 % respectively in the full term group. The study concluded that extremely preterm children require intervention to support development and reduce behavioral problems. Ten Year Follow Up of Children Born Before 29 Gestational Weeks: Health, Cognitive Development, Behaviour and School Achievement. Stjernqvist K, Svenningsen NW. Department of Psychology, Lund University, Sweden. Acta Paediatr, May 1999; 88 (5): 557-62.
31. Cognition, school performance and behavior were assessed at 8 years of age in 132 very low birth weight children who were otherwise free of major sensineural impairments and were compared with a control group of full term normal birthweight children. While the very low birth weight children were developing normally in many academic and social areas they were significantly inferior on tests of cognition, including tests of intelligence and visual memory and on teachers’ reports of motor skills and intelligence. Proportionally more very low birth weight children (20.5%) than normal birth weight children (5.9%) were reported by their parents to be not coping at school. Cognition, School Performance and Behavior in Very Low Birth Weight and Normal Birth Weight Children at 8 Years of Age: A Longitudinal Study. Rickards AL, Kitchen WH, Doyle LW, Ford GW, Kelly EA, Callanan C. Division of Pediatrics, Royal Women’s Hospital, Melbourne, Australia. J Dev Pediatr, December 1993; 14 (6): 363-8.
32. The intellectual, psychoeducational and functional status of a group of 129 extremely low birth weight children born between 1977-1981 and weighing 501 to 1,800 grams at birth were compared with a matched control group. The children were tested at an average unadjusted age of 8 years. The average IQ was 91 for extremely low birth weight children and 104 for the control group. Between 8 to 12% scored in the abnormal IQ range compared with 1 to 2% of the control group. The low birth weight children did less well on reading, spelling and math tests and their motor performance and visual motor integration were poorer. Approximately 15% of the extremely low birth weight study participants perfomred in the abnormal range on the Vineland Adaptive Behavior Scales. Although about 2/3rds fo the low birth weight children performed in the normal range on intellectual measures they were significantly disadvantaged on every measure tested. Cognitive Abilities and School Performance of Extremely Low Birth Weight Children and Matched Term Control Children at Age 8 Years: A Regional Study. Saigal S, Szatmari P, Rosenbaum P, Campbell D, King S. Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada. J Pediatri, May 1991; 118 (5): 751-60. <
33. A study was conducted to examine developmental and educational outcomes in a group fo predominantly white, middle class, extremely low birth weight children (less than 1,000 grams birthweight). Fifty four extremely low birthweight children with an average age of 7 were compared to a children in a control group matched for gender, race and socioeconomic factors and were sorted to low and normal birthweight groups. Teachers’ reports, special education evaluations, and test of cognitive, motor, language and visual motor integration abilities were studied. Fifty percent of the extremely low birth weight children were in regular classrooms compared to 70% of low birth weight children and 93% of full term children. The extremely low birth weight children scored significantly lower than the comparison groups on all tests. While 79% of the extremely low birthweight children had average cognition scores, they average 14 to 17 points lower than the two comparison groups. Twenty percent of the extremely low birth weight children had significant disabilities including cerebral palsy, mental retardation, autism and low intelligence with severe learning problems. The study concluded that there is an increasing need for special services with decreasing birth weights. Even with optimal socioeconomic environments, 20% of extremely low birthweight children are significantly disabled and 1 out of every 2 extremely low birth weight children requires special educational services. Extremely Low Birth Weight Children and Their Peers, A Comparision of School-Age Outcomes, Halsey CL, Collin MF, Anderson CL. Loyola University Medical Center, Maywood, ILL, USA Arch Pediatric Adolesc Med August 1996; 150 (8): 790-4.
34. Children with a birthweight of 2,000 grams or less born in Merseyside, England from 1980-1981 were assessed at age 8. The children and a matched control group were assessed using the Wechsler Intelligence Scale for Children (WISC) , the Neale analysis of Reading ability and the Stott-Moyes-Henderson test of Motor Impairment (TOMI). Children with low birth weight had a lower WISC IQ score, a lower reading age, and poorer motor performance. Clinical and Subclinical Deficits at 8 Years in a Geographically Defined Cohort of Low Birthweight Infants. Pharoah PO, Stevenson CJ, Cooke RW, Stevenson RC. Department of Public Health, University of Liverpool, Arch Dis Child, April 1994; 70 (4): 246-70.
35. Fifty one children who were born at the same hospital in Liverpool, England, with weights of 1,250 grams or less were followed through age 8. The extremely low birth weight group of 8 year olds were compared with a control group of the same age, race, economic group and sex. The low birth weight children performed less well on basic math tests, spelling tests, and tests of motor impairment. Twenty three percent of very low birth weight children were having difficulty with one or more school subjects compared with 19% of controls and 26% had difficulties in 2 or more areas compared with 3% of the control group. Teachers identified characteristics typical of emotional disorders and overactivity more frequently among the very low birthweight group. The study concluded that children with birthweights of 1,250 grams or less and no major impairment have a high frequency of learning difficulties that become more apparent with advancing age. Outcome at 8 Years for Children with Birth Weights of 1,250 Grams or Less. Marlow N, Roberts L, Cooke R. Department of Child Health, Liverpool Maternity Hospital. Arch Dis Child, March 1993; 68 (3 Spec No): 286-90.
36. Neurodevelopmental, health and growth outcomes for 28 six year olds weight birthweights of less than 1,001 grams were compared with a control group of 26 full term birth children. Sixty one percent of the extremely low birth weight children had mild or moderate to severe neurological problems compared with the control group children (23%). A significant portion of extremely low birthweight children had no severe disabilities, but many had dysfunctions likely to affect learning and behavior in school. Neurodevelopmental, Health and Growth Status at Age 6 Years of Children with Birth Weights Less than 1,001 Grams. Teplin SW, Burchinal M, Johnson-Martin N, Humphry RA, Kraybill EN. Clinical Center for the Study of Development and Learning, Frank Porter Graham Child Development Center, University of North Carolina, J Pediatri, May 1991; 118 (5): 768-77.
27. Thirty four long term survivors of a five year period (1977-1981) weighing 1,000 grams or less at birth were followed up at 8 to 11 years of age. Three (8.8%) of the children had severe functional handicap, seven (20.6%) had moderate impairments with the need for special schooling. Twenty four (70.6%) attended normal school but 7 (20.6%) needed special help. Infants Weighing 1,000 Grams or Less at Birth. Outcome at 8-11 Years of Age. Vekerdy-Lakatos Z, Lakatos L, Ittzes-Nagy-B. Department of Pediatrics, University Medical School, Debrecen, Hungary, Acta Paediatr Scand Suppl 1989; 360: 62-71.
38. This study tested the hypothesis that very low birth weight children (less than 1.5 kg) whose head size is not normal by 8 months (adjusted age) have significantly poorer growth and neurocognitive abilities at school age than very low birth weight children with a normal head size at eight months. A group of 249 children born from 1977 to 1979 were evaluated at age 8 to 9 years; the 33 children with subnormal head sizes at the age of 8 months had significantly lower average birth weights and higher neonatal risk scores (71 versus 53) and at the age of eight years had a higher incidence of neurologic impairment (21% versus 8%) and lower IQ scores (average verbal 84 versus 98%). The conclusions of the study indicate that in very low birth weight infants, pernatal growth failure, as evidenced by a subnormal head circumference at 8 months of age, is associated with poor cognitive function, academic achievement and behavior at 8 years of age. Effect of Very Low Birth Weight and Subnormal Head Size on Cognitive Abilities at School Age. Hack M, Breslau N, Weissman B, Aram D, Klein N, Borawski E. Department of Pediatrics, School of Medicine, Case Western Reserve University, Cleveland, OH. New England Journal of Medicine, July 25, 1991; 325 (4): 231-7.
39. In 1990 to 1992 a study was conducted in which randomly selected and evaluated low birthweight and normal birthweight children from the 1983-1985 newborn lists of two major hospitals in Southeast Michigan. Low birth weight children scored significantly lower than normal birth weight children on tests measuring language, spatial., fine motor, tactile and attention abilities with appropriate controls for site, race, maternal IQ and education. Analysis revealed that test performance varied within birth weight levels and that performance continued to improve with increased birth weight well above 3,000 grams. Low Birth Weight and Neurocognitive Stauts at Six Years of Age. Breslau N, Chilcoat H, DelDotto J, Andreski P, Brown G. Department of Psychiatry, Henry Ford Health Sciences Center, Detroit, MI. Biol Psychiatry, Sept 1, 1996; 40 (5): 389-97.
40. Survival of extremely low birth weight infants, (less than 1,000 grams) has increased. From the period of 1943 to 1945 the survival rate of infants born weighing less than 800 grams was 0% but increased to 49% to 70% for the period 1994-1995. Rates of cerebral palsy. mental retardation, blindness and deafness have remained stable in the 1980’s and 1990’s. There is evidence. however, that the percent of functional limitations may be increasing as the requirement for special education resources among very low birthweight infants remains high at 44% to 56%. Neuropsychological and Functional Outcomes of Very Low Birth Weight Infants, Vohr BR, Msall ME. Women and Infants Hospital, Child Development Center of Rhode Island Hospital, Brown University School of Medicine, Providence, RI. Semin Perinatol, June 1997; 21 (3): 202-20.
41. A study was conducted in which very low birth weight infants were compared with heavier low birth weight infants and normal birth weight children to assess the risk of behavior problems and school difficulty. Analysis revealed that 34% of very low birth weight children could be characterized as having school difficulty compared with 20% of heavier low birth weight children and 14% of normal birthweight children. Very low birthweight and hyperactivity scores contributed, independent or other sociodemographic factors, to the risk of academic problems. Very Low Birth Weight Children: Behavior Problems and School Difficulty in a National Sample. McCormick MC, Gortmaker SL, Sobol AM. Department of Behavioral Sciences, Harvard School of Public Health, Boston, Mass. J Pediatr, Nov 1990; 117 (5): 687-93.
42. A review of 20 years experience with neonatal intensive care for very low birth weight infants indicates that an increasing proportion survive free of moderate to severe handicap. However, increasing literature suggests that early findings may be insufficient to characterize later outcomes, particularly problems encountered as children enter school. The study concludes that further definition of long term outcomes for very low birth weight children is critical to assess the utility of neonatal intensive care unit interventions and at the individual level for counseling families as to the health and educational needs of these children. Long Term Follow Up of Infants Discharged from Neonatal Intensive Care Units. McCormick MC. Joint Program in Neonatology, Harvard Medical School, Boston, Mass. JAMA, March 24-31, 1989; 261 (12): 1767-72.
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