Diabetic nephropathy and pregnancy: the effect of ACE inhibitors prior to pregnancy on fetomaternal outcome

Background Diabetic nephropathy is associated with an increase in perinatal mortality and morbidity in uncontrolled pregnant patients. Recently angiotensin converting enzyme inhibitor (ACE-I) was shown to improve the disease status in non-pregnant subjects. The purpose of this study was to examine the effect of prepregnancy treatment of insulin-dependent diabetes mellitus (IDDM) nephrotic women with captopril angiotensin converting enzyme inhibitor (ACE-I), on maternal renal function throughout pregnancy and on the fetomaternal outcome. Methods Eight IDDM nephrotic patients planning pregnancy were treated with captopril for a minimum of 6 months prior to conception together with intensive insulinmanagement. Conception was allowed when proteinuria was <500 mg/day and euglycaemia was achieved. At conception captopril was discontinued. Results At the beginning of captopril treatment, proteinuria was 1633±666 mg/day. Atconception, proteinuria dropped to 273±146 mg/day (P=0.0000) and increased gradually over the three trimesters to 593±515, 783±813, and 1000±1185mg/day respectively (P=0.2 between the trimesters); declining to 619±411mg/day (P=0.0002 vs conception) 3 months after delivery. Only in two patients (25%) did proteinuriaexceed1000 mg/day during pregnancy. There was no significant change in any of the other renal function tests: CCT, serum creatinine, uric acid, K⁺and blood pressure. However, there were three cases of PET just prior to delivery. Maternal glycaemic control improved significantly prior to conception (P= 0.002) and remained euglycaemic (reflected by daily glucose profile, HbA1C and fructosamine) throughout gestation. Perinatal outcome was excellent.