P.O.D. Pharoah

Consequences of in-utero death in a twin pregnancy.

Summary Background Twins have a higher mortality and morbidity than singletons and, among twins, the surviving co-twin of a fetus that dies in utero is particularly at risk. We did a cohort study to quantify mortality and serious morbidity in co-twin survivors of fetuses that died in utero. Methods We collected data of all registered twin births in England and Wales between 1993 and 1995 in which one twin was registered as having died in utero. Copies of all death certificates of these fetuses and death certificates of live-born co-twins of fetuses that died in utero were obtained from the Office for National Statistics. A questionnaire was sent to the general practitioners of all surviving co-twins to find out if the child had any disability. Findings There were 434 fetal death/live-birth same-sex twin pairs. Among the live births, there were 59 neonatal deaths, seven postneonatal deaths (first 28 days), and five infant deaths ( Interpretation The live-birth co-twin of a fetus that died in utero is at increased risk of cerebral impairment, the overall risk is 20% (95% Cl 16–25). The gestational-age-specific prevalence of cerebral palsy after fetal death of the co-twin is much higher than that reported for the general twin population.

A HYPOTHESIS FOR THE AETIOLOGY OF SPASTIC CEREBRAL PALSY : THE VANISHING TWIN

The aetiology of spastic cerebral palsy (CP), in the majority of cases, is not known but the general consensus is that cerebral impairment occurs prepartum. In monochorionic twin pregnancies, death of one twin late in gestation is recognised as being an important risk factor for the surviving cotwin to have CP. It has been suggested that a significant proportion of singletons with spastic CP may be the result of death of a cotwin in the second half of gestation. In this paper it is hypothesised that spastic CP of unknown aetiology is the result of the death of a monochorionic cotwin and that the death of the cotwin may impair the neurological development of the survivor throughout gestation. If so, vanishing‐twin syndrome, which is now a recognised phenomenon revealed by ultrasound examination in early pregnancy, is important in the aetiology of spastic CP.

COST OF NEONATAL INTENSIVE CARE FOR VERY-LOW-BIRTHWEIGHT INFANTS

A detailed costing of the Mersey regional neonatal intensive care unit was made for 1983 (at 1984 prices) for three levels of care; costs per inpatient day were 297 pounds, 138 pounds, and 71 pounds for intensive, special, and nursery care, respectively. Regression of ungrouped patient-specific costs against birthweight showed the explanatory power of birthweight to be negligible. The average cost per very-low-birthweight (less than 1500 g) infant was 4490 pounds for a survivor and 3446 pounds for a non-survivor. A similar study elsewhere showed an almost six-fold difference in cost between survivors and non-survivors. It is postulated that medical management policy largely determines this difference and is crucial to any investigation of cost-efficiency.

Twins and cerebral palsy

In a national follow‐up study of twin births, monozygous compared with dizygous twins were at significantly increased for both to die in utero, one to die in utero and the co‐twin to die in infancy, or both to be livebirths but both die in infancy. The prevalence of cerebral palsy among survivors of a co‐twin fetal death was 80.2 and other cerebral impairment was 107.0 per 1000. Many apparently singleton cases of cerebral palsy and impairment may be due to fetal death of a twin that has not been recognized or has been recognized but not registered.

Predicting costs and outcomes of neonatal intensive care for very low birthweight infants

A geographically determined cohort of all infants of less than 1,500 g born in 1980 and 1981 were clinically followed up to age four to determine their disabilities which were classified as mild, moderate or severe. A quality adjustment coefficient, determined by the severity of the disability, was used to calculate the number of quality adjusted lives produced. The total cost of care for these children was assessed as the sum of hospital costs to age four (which were specifically determined) and an estimate of the life-time costs of care of disabled children from information provided by the Education and Social Service departments. A very poor predictive power of birthweight with cost was obtained with the ungrouped birthweight data, whereas clinical factors explained up to 60% of the variance of the initial hospital costs for survivors and up to 30% of the variance of life-time costs and the cost of quality adjusted lives produced. Rules for the allocation of resources based on discrimination by birthweight are flawed but the application of clinical discretion is important.