【Abstract】 Objective To explore the correlation between gestational reproductive tract infections and the occurrence of maternal threatened abortion. Methods A retrospective analysis was conducted. 62 pregnant women with threatened abortion treated in our hospital from July 2015 to July 2016 were selected as the observation group. Another 60 normal pregnant women who received delivery in our hospital during the same period were selected as the control group. The pregnant women in both two groups received the detection of the positive rate of leucorrhea routine microscopy, ureaplasma urealyticum (UU) and chlamydia trachomatis (CT). Results For leucorrhea routine examination items, the percentage of white blood cells, the percentage of cleanliness ⅢⅣ and candida positive rate in the observation group were significantly higher than those in the control group, and the differences were statistically significant (P＜0.05). There was no significant difference in the positive rate of lactobacillus between two groups (P＞0.05). The total percentage of UU and CT infection in the observation group was significantly higher than the control group, and the difference was statistically significant (P＜0.05).The levels of IL1, TNFalpha and IL8 in the observation group were significantly higher than those in the control group (P＜0.05).Conclusion The abnormal vaginal discharge rate, UU positive rate and CT positive rate and inflammatory factor levels in pregnant women with threatened abortion were significantly higher than those in normal pregnant women, which may be the important causes of threatened abortion. Therefore, the pregnant women should pay attention to strengthening the prenatal examination, and take active and effective treatment to improve the adverse pregnancy outcomes.