Doppler flow velocimetry of the uterine and uteroplacental circulation in pregnancies complicated by insulin-dependent diabetes mellitus

Abstract

In forty-three pregnancies complicated by insulin-dependent diabetes mellitus, 16 classified White B, 11 White C, 8 White D and 8 White R or F, the resistance-index (PR index) in the main part of the uterine artery and arcuate uterine arteries was measured by duplex-pulsed wave Doppler ultrasound. Recordings of 24 hours' blood glucose profile and glycosylated hemoglobin were parameters of glycemic control. Vascular resistance in the main uterine artery decreased with proceeding gestation as a non-diabetic pregnancy. The uterine artery supplying the placental had lower resistance than the opposite side, with a mean PR index of 0.559 (SD 0.117) and 0.622 (SD 0.133), respectively. The mean difference between both sides was 0.062 (SD 0.102) (p < 0.001). The uterine artery PR index was slightly higher in the presence of evident morphological vasculopathy, with a mean PR index of 0.591 (SD 0.104) in White D*/R/F diabetics and 0.545 (SD 0.063) in White B/C/D#, respectively (p = 0.148). Additionally more than half of the diabetics without manifest complications (B/C/D#) showed a persistent notch. Long- and short-term glycemic control was unrelated to vascular resistance in the uterine artery, with correlation coefficients of 0.027 (p = 0.746) and 0.051 (p = 0.537) for glucose and HbA1C, respectively. Doppler velocimetry could not predict diabetic specific fetal mobidity. Vascular resistance in the uterine arcuate arteries was significantly lower in the subplacental region, with a mean PR index of 0.367 (SD 0.056) compared to 0.427 (SD 0.064) in areas distant to the placenta (p < 0.0005). It was not related to vasculopathy elsewhere. in patients with diabetic vasculopathy the uterine artery is also affected, but there is no relationship with long- or short-term parameters of glycemic control. Doppler flow velocimetry of the uterine artery is a poor predictor of diabetes-specific fetal morbidity; if normal ranges of non-diabetic pregnancies are used for reference. Because of significantly different vascular resistance in the two main uterine arteries, mean values of both-side measurements should be used for analysis, whenever possible.