Glycaemic control is associated with pre-eclampsia but not with pregnancy-induced hypertension in women with type I diabetes mellitus.
OBJECTIVE
To investigate the association between glycaemic control and hypertensive pregnancy complications.


METHODS
From 1988 to 1997, we followed up 683 consecutive non-selected pregnancies in women with Type I (insulin-dependent) diabetes mellitus. Glycaemic control was assessed by assay of HbA1c. Pre-eclampsia was defined as diastolic blood pressure of 90 mmHg or more at the end of pregnancy after an increase of 15 mmHg or more, combined with proteinuria of 0.3 g or more for 24 h. Pregnancy-induced hypertension was defined similarly but without proteinuria. The same criteria were applied to a control group of 854 non-selected non-diabetic women.


RESULTS
Pre-eclampsia developed in 12.8% of the women with diabetes (excluding those with nephropathy before pregnancy) and in 2.7% of the control women (odds ratio 5.2; 95% CI 3.3-8.4). In multiple logistic regression, glycaemic control, nulliparity, retinopathy and duration of diabetes emerged as statistically significant independent predictors of pre-eclampsia. The adjusted odds ratios for pre-eclampsia were 1.6 (95% CI 1.3-2.0) for each 1% increment in the HbA1c value at 4-14 (median 7) weeks of gestation and 0.6 (0.5-0.8) for each 1% decrement achieved during the first half of pregnancy. Changes in glycaemic control during the second half of pregnancy did not significantly alter the risk of pre-eclampsia. Unlike pre-eclampsia, the risk of pregnancy-induced hypertension was not associated with glycaemic control.


CONCLUSIONS
In women with Type I diabetes, poor glycaemic control is associated with an increased risk of pre-eclampsia but not with a risk of pregnancy-induced hypertension.
Hiilesmaa
V
V
Department of Obstetrics and Gynaecology, Helsinki University Central Hospital, Helsinki, Finland.
Suhonen
L
L
Teramo
K
K
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism*; D001794:Blood Pressure; D002585:Cesarean Section; D003922:Diabetes Mellitus, Type 1 / Q000503:physiopathology*; D003928:Diabetic Nephropathies / Q000503:physiopathology; D003930:Diabetic Retinopathy / Q000503:physiopathology; D005260:Female; D005500:Follow-Up Studies; D005865:Gestational Age; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D006973:Hypertension / Q000453:epidemiology* / Q000503:physiopathology; D011225:Pre-Eclampsia / Q000453:epidemiology*; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000453:epidemiology* / Q000503:physiopathology; D011254:Pregnancy in Diabetics / Q000150:complications / Q000503:physiopathology*; D012189:Retrospective Studies; D012307:Risk Factors; D015430:Weight Gain
D001786:Blood Glucose; D006442:Glycated Hemoglobin