Background: Urine sediment parameters of pregnant women are different from those of non-pregnant women, and it is necessary to establish reference intervals for pregnant women. The aim of this study was to establish reference intervals of white blood cell (WBC), red blood cell (RBC), bacteria (BACT), squamous epithelial cell (EC), small round epithelial cell (SRC), and mucous strands (MUS) for urine sediment test of pregnant women using a UF-1000i analyzer as the detection device. The differences between pregnant women and non-pregnant women in terms of the aforementioned parameters as well as the differences of such parameters in different trimesters of pregnancy were clarified.
Methods: The experimental subjects were divided into two groups: the experiment group (612 healthy pregnant women) and the control group (582 healthy non-pregnant women). Subjects of both groups are women between the age of 22 and 46. The urine specimens were analyzed using the Sysmex UF-1000i analyzer, followed by manual correction. A statistical analysis was performed by SPSS 22.0. Results were considered significant at p < 0.01.
Results: The pregnancy reference intervals of WBC, RBC, BACT, EC, SRC, and MUS were 0 ~ 30/µL, 0 ~ 23/µL, 0 ~ 698/µL, 0 ~ 28/µL, 0 ~ 8/µL, and 0 ~ 3/µL, respectively. In the experiment group, the concentrations of WBC, BACT, EC, and SRC were significantly higher than those of the control group (p < 0.01), while the concentrations of RBC and MUS were significantly lower than those of the control group (p < 0.01). The inter-trimester differences in terms of the concentrations of WBC, BACT, EC, and SRC were statistically indistinguishable (p > 0.05). However, the concentration of RBC was significantly lower with the increase of trimester of pregnancy (the comparison between the first trimester with the second trimester: p = 0.000 < 0.01; the comparison between the second trimester and the third trimester: p = 0.004 < 0.01). The WBC, BACT, EC, and SRC had moderate intercorrelations (0.569 ~ 0.681, p < 0.01).
Conclusions: There were significant differences in the aforementioned parameters between the two groups. The intervals of WBC, RBC, BACT, EC, SRC, and MUS for urine sediment analysis of healthy pregnant women using a UF-1000i should be established.