Ultrasonic tissue characterization of the placenta: is it of clinical value?

Placentas of 84 antenatal patients have been examined throughout pregnancy (14-40 weeks of gestation). The coefficient of variation (the standard deviation divided by the mean) of echo-peak amplitude distributions obtained from placental images was used to characterize the placentas in different groups. Placentas of smokers yielded higher coefficient of variation values throughout pregnancy (P less than 0.05). This placental texture index was significantly lower for nonsmoking mothers of low-birth-weight babies after 30 weeks of gestation (P less than 0.001). Quantitative analysis of placental appearance may be of clinical value in selecting nonsmoking women at risk for low-birth-weight babies during the third trimester.