Transient improvement in glycemic control. The impact of pregnancy in women with IDDM

Good glycemic control throughout pregnancy in patients with diabetes is of paramount importance but often appears to deteriorate in the postpartum period. The aim of this study was to ascertain the timing of the improvement in glycemic control associated with pregnancy in women with IDDM and to examine changes in glycemic control after delivery.

Peripartum glycemic control was assessed in a retrospective study of 30 women with IDDM whose age was 28 +/- 6 years (means +/- SD) and whose diabetes duration was 14 +/- 6 years.

Mean total HbA1 fell incrementally from a peak at 2-3 years preconception to a nadir between 24 weeks and term, only to return to preconception levels within a year after delivery. Of the 30 women, 15 (50%) attained an HbA1 in the nondiabetic range for pregnancy at some point during their pregnancy, and 7 (23%) women achieved this by 24 weeks gestation. Women with an HbA1 > 9% at booking had a significantly higher HbA1 at 0-6 and 6-12 months preconception, and throughout pregnancy their HbA1 was significantly higher. After delivery, attendance rates at routine diabetes review clinics were low, with 11% of women not attending for longer than 24 months.

Nearly all women with IDDM can achieve near normoglycemia during pregnancy, irrespective of previous glycemic control, although those with high HbA1 levels at booking are less likely to achieve this. After delivery, glycemic control deteriorates. Efforts to improve glycemic control should be intensified in the preconception period and maintained after delivery. The poor postpartum attendance at diabetes clinics requires specific action.