Section B: Mortality Statistics in Wales – Neonatal

  1. Neonatal mortality in Wales
  2. Cause of neonatal death in Wales
  3. References
Neonatal mortality in Wales (deaths after livebirth to 27 completed days)

Neonatal mortality rate is a key measure of health and care during pregnancy and delivery. The principal causes of neonatal death in high-income countries are complications relating to very preterm birth and congenital anomalies. The neonatal mortality rate to women usually resident in Wales, excluding late termination livebirths, in 2015 was 2.49 (95% CI 2.01, 3.08) per 1,000 livebirths (Table A11 (2)). This rate has shown an overall decline since the 1990s. The neonatal mortality rate in Wales (including late termination livebirths) in 2015 was 2.58 per 1,000 livebirths (95% CI 2.09, 3.18). Following a decline in neonatal mortality between 2000 and 2004 there has been a slight but steady reduction in neonatal mortality rates (Figure 12) and (Table A11). Similar trends are observed for neonatal mortality rates in the Welsh Health Boards and regions (Table A11). In 2014, ONS reported the neonatal mortality rate as 2.5 per 1,000 livebirths in England, 2.4 per 1,000 livebirths in Scotland, 3.9 per 1,000 livebirths in Northern Ireland, and 2.1 per livebirths in Wales ONS.

Figure 12: Neonatal deaths (excluding late terminations): 3 year rolling average rates in Wales (1995-1997 to 2013-2015)


Source: NCCHD and AWPS/MBRRACE-UK

Between Health Boards, the neonatal mortality rates for 2015 ranged from 0.82 (95% CI 0.28, 2.41) at Hywel Dda Health Board to 3.79 per 1,000 (95% CI 2.22, 6.48) at Cwm Taf Health Board. The rates between regions were 3.12 per 1,000 in North Wales, 2.91 per 1,000 in South East Wales and 1.46 per 1,000 in Mid and West Wales (Table A11).

In Wales, neonatal mortality rates are persistently higher in the two most deprived quintiles of social deprivation measured using the Welsh Index of Multiple Deprivation (WIMD) (Figure 13). Cases were allocated to the appropriate quintile of deprivation based on mother’s residence and LSOA. This figure shows that the differences in neonatal mortality rates between the least and most deprived quintiles is getting narrower. Recent analysis of trends in the neonatal mortality rate in England, up to and including 2007, showed that substantial inequalities still persist, and much of this gap is largely explained by premature births and congenital anomalies 1. Although our data does not distinguish between early and late neonatal deaths, previous work in Wales has shown that the association with deprivation is stronger for the late neonatal period 2. Preterm birth is a major cause of neonatal mortality but there is little socio-economic variation in mortality following preterm birth, indicating good access to high quality perinatal and neonatal services. However, the incidence of preterm birth is higher in more deprived areas, driving the observed socio-economic inequalities in neonatal mortality rates 3 (Table A3).

Neonatal mortality rate by deprivation quintile: five year rolling rates (1994-1998 to 2011-2015)


Source: NCCHD and AWPS/MBRRACE-UK

The funnel plot shows the neonatal mortality rates over a five-year period, 2011 to 2015 for all Health Boards (Figure 14). Between Health Boards, the neonatal mortality rates for the 5 years ranged from 1.92 in Hywel Dda Health Board to 3.05 per 1,000 in Cwm Taf Health Board. However, the rates are not adjusted for socio-demographic characteristics or clinical factors and therefore should be interpreted with caution. None of the Health Boards had a neonatal mortality rate which was beyond the 95% confidence limits over the five-year period.

Figure 14 Neonatal mortality rate (excluding late terminations) by Health Board to mothers resident in Wales: 2011- 2015


Source: NCCHD and AWPS/MBRRACE-UK

Cause of neonatal death in Wales

The CODAC Classification system for neonatal deaths was used, to give as much information as possible into the underlying cause of death or events leading up to death. This will thus enable us to explore any trends or variation in causes of death and identify areas that can be addressed.

Classification using the CODAC Classification system indicates that, between 2013-2015, neonatal reasons are the leading cause of neonatal death by CODAC classification (46%) (this category is broken down further (Figure 15c)), followed by congenital anomaly (18%) and intrapartum (8%).

Figure 15a: Single main cause of neonatal deaths using CODAC classification: 2013-2015

Total: 235

Figure 15b: Single main cause of neonatal deaths using CODAC classification: 2015

Total: 83

When the neonatal category was broken down further extreme prematurity was the leading cause of death. 11% of cases were unspecified or other. The number of deaths in this category was small though.

Figure 15c: Neonatal category broken down to level 2 of CODAC classifications: 2015

Total: 44

When the congenital anomaly category was broken down further the following results were seen. The number of deaths in this category was small though (n=15).

Figure 15d: Congenital anomaly broken down to level 2 of CODAC classifications: 2015

Total: 15

Source: AWPS/MBRRACE-UK

References

1.         Smith LK, Manktelow BN, Draper ES, Springett A, Field DJ. Nature of socioeconomic inequalities in neonatal mortality: population based study. BMJ 2010;341:c6654

2.         Guildea ZE, Fone DL, Dunstan FD, Sibert JR, Cartlidge PH. Social deprivation and the causes of stillbirth and infant mortality. Archives of Disease in Childhood 2001;84(4):307-10

3.         Smith LK, Draper ES, Manktelow BN, Dorling JS, Field DJ. Socioeconomic inequalities in very preterm birth rates. Archives of disease in childhood. Fetal and neonatal edition 2007;92(1):F11-4