Near-infrared Spectroscopy: Differences in Placental Oxygenation in Relation to Ultrasound Maturation Grade in physiologIcal Term Pregnancies

The aim was to compare placental oxygenation in low risk, uncompli-cated, term pregnancies measured by near-infrared spectroscopy (NIRS) in relation to the placental maturity grade determined by ultrasound assessment according to Grannum scale. The study included 34 singleton subjects divided into two groups accord-ing to placental maturation: low grade (Grannum 0-1; n=10) and high grade (Gran-num 2-3; n=24). In each study subjects, measurement was performed at two sites: (a) test site above the central part of the placenta, and (b) control site out of placenta on lower abdomen, in medial line, 3 cm from the symphysis. Student's t-test was used to compare tissue oxygenation index (TOI) values among the study groups. The normality of distribution was demonstrated by the Kolmogorov-Smirnov test.