The fetal arterial vasculature in placentas of insulin-dependent diabetic mothers.

Abstract

Seventeen placentas from insulin-dependent diabetic women and ten placentas from non-diabetics were studied with angiography. The fresh placentas were injected in both umbilical arteries with barium sulphate suspension. After fixation in formaldehyde, the placentas were X-rayed, intact and after being sliced in 0.8 cm slices. There were two clearly distinguishable types of intracotyledonary arteries. Type A is long, narrow and usually runs in the periphery of the cotyledon; type B is wider and usually runs towards the centre of a cotyledon. The cotyledons were classified according to the distribution of these two types of arteries. Type I contained only A-arteries and Type II, both A- and B-arteries or only B-arteries. Twelve per cent of the cotyledons in the control group belonged to Type I, but in the diabetes group 29 per cent. One block of tissue from every placenta was examined histologically to check that the contrast medium filled the stem villus vessels but not the capillaries in the peripheral villi. The histological sections in both groups were compared. Endarteritis appeared to be a feature of the diabetes placenta. The angiographic findings were compared with results of previous direct light microscopical studies. A high percentage of hypovascular villi was found in placentas with a high number of Type I cotyledons.