Biochemical parameters of the retroplacental blood in preeclampsia

BACKGROUND: The efficiency of existing methods of predicting preeclampsia is far from 100%, which dictates the need to search for new additional markers. Retroplacental blood is a unique and practically unstudied biological substrate, and its composition probably influences the course of pregnancy. This study aimed to investigate the biochemical parameters of retroplacental blood in preeclampsia.

MATERIALS AND METHODS: The study included 53 pregnant women who were divided into two groups: the first group had normal pregnancy (n=28), and the second group had severe preeclampsia (n=25). All pregnant women underwent cesarean section at delivery. Peripheral and retroplacental blood sera were examined. Sampling was performed immediately after mechanical separation of the placenta and separation of the afterbirth. Levels of alanine transaminase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), total protein, albumin, urea, creatinine, total and direct bilirubin, glucose, and uric acid were determined on a Beckman Coulter AU480 biochemical analyzer (Germany).

RESULTS: The biochemical composition of retroplacental and peripheral blood showed significant differences (p <0.05). In physiologic pregnancy, the levels of ALT, AST, LDH, urea, creatinine, direct bilirubin, and uric acid were significantly (p <0.05) higher by 1.9, 20.1, 11.4, 1.14, 1.19, 2.0, and 1.15 times, respectively, whereas glucose levels were 1.5 times lower in the retroplacental blood. In patients with severe preeclampsia, the levels of AST, LDH, creatinine, total and direct bilirubin, and uric acid were significantly (p <0.05) increased in retroplacental blood by 11.7, 11.5, 1.3, 1.2, 2.2, and 1.11 times, respectively, and glucose levels decreased 1.57 times. When comparing the biochemical composition of the peripheral blood of the first and second groups, reliable differences (p <0.05) were noted only in ALT, AST, total protein, albumin, urea, and creatinine. However, in the retroplacental blood under physiologic pregnancy and preeclampsia, significant differences (p <0.05) were found only for urea, creatinine, and uric acid levels.

CONCLUSION: The study of the biochemical composition of the retroplacental blood can provide a more complete picture of the pathogenesis of preeclampsia.