[Relationship between PGI2, TXA2 and threatened preterm].

The objectives of this study were to investigate the levels of 6-keto-PGF1 alpha, TXB2 and progesterone in plasma and cervical mucus of women with threatened preterm labor (Group I), term labor (Group III) versus their controls (Groups II and IV) respectively and to investigate the relationship between these substances and threatened preterm labor. One case was matched with one control (pregnant woman) by weeks of gestation. Radioimmunoassay was used to determine the levels of 6-keto-PGF1 alpha, TXB2 and progesterone. Statistical differences were assessed by student t test. The results showed that the levels of TXB2, 6-Keto-PGF1 alpha in plasm from women with term labor and threatened preterm labor were higher than those of the control groups (P < 0.001) respectively. The ratios of 6-keto-PGF1 alpha and TXB2 were lower than their controls (P < 0.001) respectively. No differences in the levels of progesterone were noted between the labor groups and their control groups (P > 0.05) respectively. The results observed in cervical mucus were in line with there in plasma. These results suggest that the levels of PGI2, TXA2, and PGI2/TXA2 ratio were associated with the onset of term labor.