Normal sonographic values of maternal spleen size throughout pregnancy

This study aims to establish normal range of sonographically measured maternal spleen size throughout pregnancy. Currently, 288 healthy pregnant women between 6 and 42 weeks' gestation underwent ultrasonographic measurements of spleen length and width. The relationships between ultrasound measurements with prepregnancy body mass index (BMI) and gestational age were assessed using the Pearson correlation coefficient. A linear regression model was applied to construct the appropriate equation for measuring the spleen area relative to BMI and gestational age. A significant correlation (R) was found between gestational age and spleen dimensions length (R = 0.486; p < 0.001), width (R = 0.455; p < 0.001) and area (R = 0.522; p < 0.001)) as well as between prepregnancy BMI and spleen length [(R = 0.314; p < 0.001), width (R = 0.380; p < 0.001) and area (R = 0.413; p < 0.001)]. We divided the spleen area by the BMI, thus enabling to perform a linear regression analysis with gestational age (weeks) as an independent continuous variable. A high multiple correlation (R) between spleen area and this variable was found (R(2) = 0.47; p < 0.001). The equation [spleen area/BMI = 1.598 + 0.032 x gestational age in weeks] was performed for calculating the spleen area throughout pregnancy. A significant overall growth pattern of spleen area in pregnancy with increasing gestational age was found. Normograms from these data can be used to evaluate splenomegaly throughout pregnancy.