Background:
Poorly controlled diabetes in pregnancy is associated with an increased rate of congenital anomalies and adverse neonatal outcomes. Data from the United Kingdom showed that the relative risk of a major congenital anomaly in a patient with type 1 or 2 diabetes is 2.2 [1]. In New Zealand, the rate of congenital anomalies has previously been quoted as 5.5% in type 1 diabetic patients, and 4.4% in type 2 diabetes. [2]
Method:
We conducted a prospective audit of women with type 1 and 2 diabetes under the care of the Diabetes in Pregnancy service at Waikato Hospital between 2007 and 2012. We analysed the characteristics of women who had babies with minor or major congenital anomalies. Other risk factors for congenital anomalies are explored.
Results:
102 patients with type 1, and 116 patients with type 2 diabetes, were analysed. 14 women (6.4%) had babies with congenital anomalies. Some babies had more than one anomaly. Of these 14 women, only 50% have a recorded preconception HbA1c (7/14). Of these seven patients, one was type 2 and six were type 1. The average pre-conception HbA1c was 70mmol/mol (8.6%). Skeletal anomalies were the most commonly observed (5 babies), followed by renal tract anomalies (3 babies). Preconception folic acid was only taken in 4/14 patients (29%).
Conclusion:
This case series highlights the need for good preconception advice in diabetic women of childbearing age. Good glycaemic control prior to conception and in the early stages of pregnancy is vital in helping to ensure a good pregnancy outcome.
References:
1. Macintosh, M. Fleming, K, Bailey, J et al. Perinatal mortality and congenital anomalies in babies of women with type 1 or type 2 diabetes in England, Wales, and Northern Ireland: population based study. BMJ 2006; 233: 170
2. Farrell, T. Neale, L, Cundy, T. Congenital anomalies in women with type 1, type 2 and gestational diabetes. Diabetic Medicine. 2002; 19:322-326