Pregnancy does not induce or worsen retinal and peripheral nerve dysfunction in insulin-dependent diabetic women

In order to verify whether pregnancy induces or worsens diabetic retinopathy or somatic and autonomic neuropathy, 16 insulin-dependent diabetic (IDDM) pregnant women, 14 age-matched nondiabetic pregnant women, and 12 IDDM nonpregnant women matched for age and disease duration were studied. Plasma glucose, HbA(1c), and fructosamine were repeatedly assayed during pregnancy. Retinopathic and neuropathic endpoints were evaluated through ophthalmoscopy, electrophysiology of left peroneal and sural nerves (motor and sensory conduction velocities), and cardiovascular autonomic tests (deep breathing, cough test, lying-to-standing). In the IDDM pregnant women, evaluations were performed three times during pregnancy and 6 months after delivery. Good metabolic control was achieved during pregnancy. At baseline, nine IDDM pregnant women did not show signs of retinopathy, and seven had nonproliferative retinopathy. Only one patient showed worsening during pregnancy, but she improved after delivery. Motor conduction velocity, significantly lower in IDDM pregnant women, progressively improved, and, in the third trimester, was not significantly different from that of nondiabetic pregnant women. At baseline, none of the IDDM pregnant women had abnormal responses to cardiovascular autonomic tests. During pregnancy, the response to deep breathing appeared temporarily reduced in all pregnant women, possibly due to lowered ventilatory excursion at the end of pregnancy. In IDDM women with minimal or no retinopathy, and subclinical or no peripheral neuropathy, pregnancy does not appear to induce or worsen these complications.