ANTENATAL RISK-FACTORS FOR CHILDHOOD DIABETES-MELLITUS - A CASE-CONTROL STUDY OF MEDICAL RECORD DATA IN YORKSHIRE, UK

Environmental risk factors for childhood insulin-dependent diabetes me llitus (IDDM) have been investigated using data abstracted from the ob stetric records of mothers participating in a population-based case-co ntrol study of children (0-15 years) diagnosed with IDDM during 1993-1 994. A univariate analysis of 196 age and sex matched sets (129 triple ts, 67 pairs) gave significantly raised odds ratios (OR) for mothers o ver 35 years (OR 2.13, 95% CI 1.04-3.36) and the following exposures i n pregnancy: amniocentesis (3.85, 1.34-11.04), oedema, proteinuria and /or hypertensive disorders (1.62, 1.03-2.54), excessive weight gain (7 .12, 1.50-33.79) and complications in labour (1.49, 1.00-2.21). The ri sk previously associated with caesarean deliveries was confirmed and t he trend of increasing risk with age was significant. Adjusting separa tely for mothers with IDDM (4 cases, 0 control subjects), parity and s mall for gestational age failed to have any influence on the pregnancy risk factors or caesarean delivery. Case mothers undergoing amniocent esis were significantly younger compared to their control counterparts (p = 0.02) and the majority were given the test to determine fetal ma turity, late in pregnancy, rather than to identify chromosomal abnorma lities. Oedema, proteinuria and/or hypertension conferred an increased risk throughout pregnancy, particularly in the first two trimesters. No specific pattern of risk was present for any age group. Multivariat e modelling of the significant OR, using conditional logistic regressi on, retained excessive weight gain as significant. The overall results present a risk profile of older mothers whose babies may be exposed t o adverse intrauterine conditions and delivery by caesarean section.