This is the number of stillbirths and deaths in the first week of life/1000 total births. Stillbirths only include those fetuses of >24 weeks' gestation, but if a fetus of <24 weeks' gestation is born and shows signs of life, and then dies, it is counted as a perinatal death in the UK (if dying within the first 7 days). Neonatal deaths are those infants dying up to and including the 28th day after birth. Other countries use different criteria including stillbirths from 20 weeks and neonatal deaths up to 28 days after birth, so it is not always easy to compare statistics.
Perinatal mortality is affected by many factors. Rates are high for small (61% of deaths are in babies <2500g) and preterm babies (70% of deaths occur in the 5% who are preterm). See p 50 & p 128. Regional variation in the UK is quite marked. There is a social class variation with rates being less for social classes 1 and 2 than for classes 4 and 5. Teenage mothers have higher rates than mothers aged 20 29. From 35yrs rates rise until they are 1.5-fold higher than the low-risk group (25 35 years) by the age of >40. Second babies have the lowest mortality rates. Mortality rates are doubled for fourth and fifth children, trebled by sixth and seventh (this effect is not independent of social class as more lower social class women have many children). Rates are lower for singleton births than for multiple. Rates are higher for the offspring of mothers of Pakistani (14.6:1000) and Caribbean (15.5:1000) extraction living in the UK, as opposed to those of UK extraction (7.8:1000).
Perinatal mortality rates in the UK have fallen over the years from rates of 62.5/1000 in 1930 5 to 8.3/1000 in the 2002 for England and Wales.67 Declining mortality reflects improvement in standards of living, improved maternal health, and declining parity, as well as improvements in medical care. The main causes of death were congenital abnormalities (21%), unclassified hypoxia (asphyxia) (18%) in 2002. Previously placental conditions (16%), birth problems including cord problems (11%), and maternal conditions (8%) have been other major causes.
Of neonatal deaths the main causes are prematurity (59%) and malformation (33%).
Examples of how changed medical care may reduce mortality:
- Worldwide, treatment of syphilis, antitetanus vaccination (of mother during pregnancy), and clean delivery (especially cord techniques), have the greatest influence in reducing perinatal mortality.
- Antenatal detection and termination of malformed fetuses.
- Reduction of mid-cavity procedures and vaginal breech delivery.
- Detection of placenta praevia antenatally.
- Prevention of rhesus incompatibility.
- Preventing progression of preterm labour.
- Better control of diabetes mellitus in affected mothers.
- Antenatal monitoring of at risk pregnancies.
While we must try to reduce morbidity and mortality still further, this must not blind us to other problems that remain, such as the overmedicalization of birth; the problem of reconciling maternal wishes to be in charge of her own delivery with the immediate needs of the baby; and the problem of explaining risks and benefits in terms that both parents understand, so that they can join in the decision-making process.
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