Study On The Relationship Between Vaginal Microenvironment And Premature Delivery During Pregnancy

Objective:To grasp the status of vaginal microecology of premature and full-term pregnant women,and to explore the relationship between vaginal microecology during pregnancy,mycoplasma,chlamydia,gonococcal infection and premature delivery.Method:Two hundred pregnant and lying-in women with mycoplasma,chlamydia and gonococcus tested were enrolled in the First Affiliated Hospital of Inner Mongolia Medical University from January to December 2018.Those who delivered between 20 and 37 weeks of gestation were enrolled in the preterm group（100 cases）and those with 37 weeks or more were enrolled in the full-term group（100 cases）.The vaginal and cervical secretions of two groups of pregnant women were collected,and the vaginal microecological morphology and function were evaluated,and the mycoplasma,chlamydia and gonococcal infection were detected.The vaginal microecological characteristics of pregnant women in the two groups were summarized,and the changes of dominant physiological flora,pathogens,H₂O₂,LE（leukocyte esterase）,SNA（sialidase）,mycoplasma,chlamydia and gonococcus in the two groups were compared.Results:（1）Premature and full-term group general situation comparison:Premature and full-term group age,number of pregnancies,number of births,the number of abortions had no significant difference（P>0.05）.（2）Description of vaginal Microecology in preterm and full-term groups:95 pregnant women in preterm and full-term groups had vaginal microecology disorders;39 pregnant women in preterm group were diagnosed with BV（bacterial vaginosis）,VVC（vulvovaginal candidiasis）,TV（trichomonal vaginitis）.Among them,there were only 1 case of TV,56cases of undiagnosed pathogenic bacteria,including 20 cases of bacteriostasis;16 cases of pregnant women with vaginal microecological disorders in full-term group were diagnosed as BV,VC,no TV,79 cases of undiagnosed pathogenic bacteria,including 11 cases of bacteriostasis.（3）Comparison of the results of dominant bacteria,mycoplasma,chlamydia and gonococcus in preterm and full-term groups:60%of pregnant women in preterm group were predominant G+b（L）（gram-positive bacillus）bacteria,22%of pregnant women were predominant G-b（s）（gram-positive bacillus）;78%of pregnant women in full-term group were predominant G+b（L）.G-b（s）was the dominant bacteria in 13%of pregnant women,and there were significant differences in G+b（L）and G-b（s）between the two groups（P<0.05）.The positive rate of Mycoplasma was 43%in preterm delivery group,38%in full-term group,and there was no significant difference between the two groups（P>0.05）;chlamydia and gonococcus only had positive pregnant women in preterm delivery group and no positive patients in full-term group,but there was significant difference between the two groups（P<0.05）,and there was no significant difference between gonococcus（P>0.05）.（4）Comparisons of the incidence of BV,VVC and BV with VVC in preterm and full-term groups:The incidence of BV,VVC and BV with VVC in preterm group was 17%,12%and9%,respectively,which was significantly higher than that in full-term group（9%,4%,3%,P<0.05）.（5）The positive rates of H₂O₂,LE,SNA and H₂O₂+LE in preterm and full-term groups were compared.There was no significant difference between the two groups（P>0.05）.The positive rate of SNA was 23%in the preterm group and 9%in the full-term group.There was a significant difference between the two groups（P<0.05）.There was no significant difference in the positive rates of H₂O₂ and H₂O₂+LE between the two groups（P>0.05）.Conclusions:（1）The dominant bacterial flora in vagina of premature pregnant women are prone to change,and the isolation rate of Gram-negative bacteria is increased.（2）Vaginal infection of BV and/or VC in pregnant women can promote the occurrence of premature delivery.（3）Premature delivery is closely related to Chlamydia vaginalis infection.（4）Pregnancy rate of pregnant women with positive vaginal SNA increased.