Outcome of diabetic pregnancy Comparison of North East England with Norway December 2000 Gillian Hawthorne

Dr Hawthorne u Consultant Diabetologist based at Newcastle Diabetes Centre, Newcastle-upon-Tyne u Interested in diabetic pregnancy since 1990 u Studied with David Hadden, Belfast and Lois Jovanovic, New York

St Vincent’s declaration u Achieve pregnancy outcome in the diabetic woman that approximates that of the non diabetic woman

England and the North East

Norway Bergen Medical birth registry

Northern Diabetic Pregnancy Survey u Prospective population based survey u Perinatal mortality for diabetic pregnancy 48/1000 compared to background of 8.9/1000 u Congenital malformation rate for diabetic pregnancy 83/1000 compared to 21.3/1000

Diabetic Pregnancy outcome for the UK per 1000 Diabetes BackgroundDiabetesBackground Merseyside Northern Ireland N/A 9.7% 5% Perinatal Mortality Birth Defect

Perinatal Deaths in Norway u Perinatal deaths in diabetic pregnancy »11.8 per 1000 u Perinatal deaths in non-diabetic pregnancy »6.7 per 1000 u Perinatal deaths = stillbirth at 28 completed weeks or neonatal death <7th day of life

Aim of study u To determine if the difference in diabetic pregnancy outcome between Norway and North East England can be explained by procedural differences: u Are there differences in recording data? u Are the differences in recorded outcome real?

Methods u All data collected prospectively between 1st July 1994 and 30th June 1997 u In Norway compulsory notification of all pregnancies with gestational age of 16 completed weeks or more u In north East England notification of all diabetic pregnancy to Northern Diabetic pregnancy Survey

Standardisation of definitions u Stillbirths defined as all fetal deaths more than 24 completed weeks u Perinatal mortality all stillbirths >24 completed weeks and all live births u Congenital anomalies coded using ICD 8

u Terminations for birth defects included in both numerators and denominators u Relative risks approximated by odds ratio

Perinatal Mortality in North East England Total Number Perinatal Deaths Perinatal mortality /1000 With diabetes Without diabetes Relative risk 4.4[ ]

Perinatal mortality in Norway Total Number Perinatal Deaths Perinatal mortality /1000 With diabetes Without diabetes Relative risk 1.5 CI [ ]

Birth Defects in North East England Total Number Birth Defects Birth Defects /1000 Babies of: Mothers with diabetes Mothers without diabetes Relative risk 2.5 CI [ ]

Birth defects in Norway Birth defects in Norway Total Number Birth Defects Birth Defects /1000 Babies of: Mothers with diabetes Mothers without diabetes Relative risk 0.95 CI [ ]

Summary u In North East England - –The perinatal mortality for offspring of mothers with diabetes was 42.8/ a 4 fold increase in risk compared to offspring of mothers without diabetes –The risk of birth defects was 2.5 fold increased

Summary u In Norway –Perinatal mortality was 10.4/1000 for offspring of mothers with diabetes- 1.5 fold increase compared to offspring of mothers without diabetes –Risk of birth defects for offspring of mothers with diabetes was 0.95

Relative risks between North East England and Norway u The differences were significant [p=0.0002] for the relative risk of perinatal mortality adjusted for maternal age u The differences were significant [p=0.0008] for relative risks for birth defect adjusted for maternal age

Conclusion u In Norway the outcome of diabetic pregnancy is similar to that of the background population u Diabetic pregnancy remains high risk in North East England u Further research is required to understand what is the cause of this difference