Organisation of perinatal/neonatal care.

There is no single system, whether state run, private or mixed, that consistently produces superior perinatal results (131), although these usually emanate from jurisdictions with regionalised or centralised comprehensive antenatal and natal care, as opposed to haphazard systems of care. Again the literature is "more description than evaluation, possibly because the latter requires comparative studies or audits which have not caught up with the new technology" (132). Changes in the organisation and delivery of reproductive health care since 1960, combined with advances in treatment, have apparently had an impact on the outcome of pregnancy and newborn care, resulting in reductions in perinatal mortality, mainly through their influence on birthweight-specific mortality. The latter is a major marker of the quality of hospital reproductive health care. Changes in the distribution of weights at birth have been relatively small; consequently the proportional numbers of infants born weighing less than 1500 g, who contribute most to morbidity and mortality, has roughly tracked the birth rate and has changed little. The proportion of babies born of low weight due to prematurity and/or intrauterine growth restriction, which are mainly influenced by socioeconomic and environmental factors, has seen only a marginal reduction in most developed countries and cannot explain the fall in mortality. Many reviews (e.g. 31, 36-38, 40, 41, 43-45, 47-52, 54, 55, 66, 67, 90, 93-95) of perinatal care now accept the cause and effect relationship between enhanced perinatal care and decline in perinatal mortality. Reduction in the incidence of low birthweight between 1500 and 2500 g is attributed more to the influence of environmental and lifestyle factors, including the standard of living, housing and nutrition, the level of education and the prevalence of infections in the population. On the other hand, the incidence of infants born weighing less than 1500 g, the major contributors to perinatal morbidity and mortality in developed societies, is relatively stable across time and across different jurisdictions. It forms about 1% of all births, but is responsible for 60-75% of morbidity and mortality. It appears relatively insusceptible to improvements in standards of living and other environmental factors. It may be more dependent on biological factors controlling the onset of premature labour, the incidence of genetic or chromosomally determined disease and the prevalence of teratogens. The only way to influence these factors is through a better understanding of the mechanisms by which they operate, which should lead to the appropriate strategy for their elimination.(ABSTRACT TRUNCATED AT 400 WORDS)