J. Obstet. Gynaecol. Res. Vol. 41, No. 8: 1214–1222, August 2015
doi:10.1111/jog.12704
Incidence and risk factors of bacterial vaginosis among pregnant women: A prospective study in Maanshan city, Anhui Province, China 1†
1†
1
2
2
1
Xiu-De Li , Fei Tong , Xiu-Jun Zhang , Wei-Jun Pan , Mao-Lin Chen , Cheng-Cheng Wang , Xiang Li1, Guo-Peng Gao3, Liang Sun1 and Ye-Huan Sun1 1
Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, Hefei, Anhui, People’s Republic of China 2Department of Obstetrics and Gynaecology, Maternal and Child Health Care Hospital of Maanshan, Maanshan, Anhui, People’s Republic of China 3Anhui No. 2 Province People’s Hospital, Hefei, Anhui, People’s Republic of China
Abstract Aim: The aim of this study was to identify the incidence and risk factors of bacterial vaginosis among pregnant women. Material and Methods: Prospective data from a cohort of 668 pregnant women were used to identify potential risk factors for bacterial vaginosis during pregnancy by Cox proportional hazards regression. Results: A total of 204 incident cases of bacterial vaginosis were diagnosed in 274.8 woman-years of follow-up. The bacterial vaginosis incidence rate was 0.74 per 1 woman-year and median prevalence during follow-up was 15.6%. In the adjusted model, changing underwear nearly everyday, miscarriage history, urinary tract infection during follow-up, husbands’ education level, and concurrent trichomoniasis and candidiasis remained significantly associated with bacterial vaginosis (adjusted hazard ratio and 95% confidence interval were 1.87 [1.26–2.77]; 2.96 [1.96–4.47]; 2.41 [1.05–5.49]; 0.50 [0.32–0.77]; 1.82 [1.02–3.25]; 1.88 [1.30–2.70], respectively). Conclusion: Bacterial vaginosis during pregnancy can be affected by many factors, and some are indirectly acting factors. Further prospective studies that include a larger sample size and more information on the development of bacterial vaginosis are needed. Key words: bacterial vaginosis, China, incidence, pregnant women, risk factors.
Introduction Pregnancy is the happiest moment for most women in their life. However, many risk factors are harmful to their babies and bacterial vaginosis is one of them. Bacterial vaginosis (BV) is the most common vaginal infection in women of child-bearing age1 and can affect 4.9–49% of pregnant women.2–5 Although many clinical trials have shown conflicting evidence regarding treatment of BV during pregnancy and subsequent reduction in adverse pregnancy outcomes,6–8 many studies showed that BV was a risk factor for adverse pregnancy outcomes,
including preterm birth, low birthweight, preterm premature rupture of membranes and others,9,10 so the prevention of BV during pregnancy needs further consideration. Having a good knowledge of the risk factors for BV is critical for its prevention,11 so we need more studies about risk factors of BV. In fact, there are many studies about risk factors of BV,4,5,11–16 even prospective studies.11–15 However, among the studies about risk factors for BV during pregnancy,4,5 the majority of these studies are cross-sectional in design. As pregnancy is a special state of major physiologic changes that may influence the exposure effects of BV risk factors,
Received: June 27 2014. Accepted: January 30 2015. Reprint request to: Dr Xiu-Jun Zhang, Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, 81 Meishan Road, Hefei 230032, Anhui, People’s Republic of China. Email: [email protected] † Xiu-De Li and Fei Tong contributed equally to this work.
1214
© 2015 The Authors Journal of Obstetrics and Gynaecology Research © 2015 Japan Society of Obstetrics and Gynecology
Risk factors for bacterial vaginosis
prospective studies are significantly important for exploring the risk factors of BV during pregnancy. In April 2012, we established a cohort of pregnant women in the Maternal and Child Health Care Hospital of Maanshan, Anhui Province, China. One of the main aims of this prospective study was to examine the incidence and risk factors for BV during pregnancy.
Methods In April 2012, a cohort that was composed of pregnant women who sought prenatal care was established to identify the incidence and potential risk factors of BV during pregnancy. The study protocol was approved by the Research Ethics Committee of the University of Anhui Medical University. Before the study was conducted, the objectives and details of the study were explained to the Maternal and Child Health Care Hospital of Maanshan, to obtain their approval and support. Participating women met the following criteria: (i)
doi:10.1111/jog.12704
Incidence and risk factors of bacterial vaginosis among pregnant women: A prospective study in Maanshan city, Anhui Province, China 1†
1†
1
2
2
1
Xiu-De Li , Fei Tong , Xiu-Jun Zhang , Wei-Jun Pan , Mao-Lin Chen , Cheng-Cheng Wang , Xiang Li1, Guo-Peng Gao3, Liang Sun1 and Ye-Huan Sun1 1
Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, Hefei, Anhui, People’s Republic of China 2Department of Obstetrics and Gynaecology, Maternal and Child Health Care Hospital of Maanshan, Maanshan, Anhui, People’s Republic of China 3Anhui No. 2 Province People’s Hospital, Hefei, Anhui, People’s Republic of China
Abstract Aim: The aim of this study was to identify the incidence and risk factors of bacterial vaginosis among pregnant women. Material and Methods: Prospective data from a cohort of 668 pregnant women were used to identify potential risk factors for bacterial vaginosis during pregnancy by Cox proportional hazards regression. Results: A total of 204 incident cases of bacterial vaginosis were diagnosed in 274.8 woman-years of follow-up. The bacterial vaginosis incidence rate was 0.74 per 1 woman-year and median prevalence during follow-up was 15.6%. In the adjusted model, changing underwear nearly everyday, miscarriage history, urinary tract infection during follow-up, husbands’ education level, and concurrent trichomoniasis and candidiasis remained significantly associated with bacterial vaginosis (adjusted hazard ratio and 95% confidence interval were 1.87 [1.26–2.77]; 2.96 [1.96–4.47]; 2.41 [1.05–5.49]; 0.50 [0.32–0.77]; 1.82 [1.02–3.25]; 1.88 [1.30–2.70], respectively). Conclusion: Bacterial vaginosis during pregnancy can be affected by many factors, and some are indirectly acting factors. Further prospective studies that include a larger sample size and more information on the development of bacterial vaginosis are needed. Key words: bacterial vaginosis, China, incidence, pregnant women, risk factors.
Introduction Pregnancy is the happiest moment for most women in their life. However, many risk factors are harmful to their babies and bacterial vaginosis is one of them. Bacterial vaginosis (BV) is the most common vaginal infection in women of child-bearing age1 and can affect 4.9–49% of pregnant women.2–5 Although many clinical trials have shown conflicting evidence regarding treatment of BV during pregnancy and subsequent reduction in adverse pregnancy outcomes,6–8 many studies showed that BV was a risk factor for adverse pregnancy outcomes,
including preterm birth, low birthweight, preterm premature rupture of membranes and others,9,10 so the prevention of BV during pregnancy needs further consideration. Having a good knowledge of the risk factors for BV is critical for its prevention,11 so we need more studies about risk factors of BV. In fact, there are many studies about risk factors of BV,4,5,11–16 even prospective studies.11–15 However, among the studies about risk factors for BV during pregnancy,4,5 the majority of these studies are cross-sectional in design. As pregnancy is a special state of major physiologic changes that may influence the exposure effects of BV risk factors,
Received: June 27 2014. Accepted: January 30 2015. Reprint request to: Dr Xiu-Jun Zhang, Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, 81 Meishan Road, Hefei 230032, Anhui, People’s Republic of China. Email: [email protected] † Xiu-De Li and Fei Tong contributed equally to this work.
1214
© 2015 The Authors Journal of Obstetrics and Gynaecology Research © 2015 Japan Society of Obstetrics and Gynecology
Risk factors for bacterial vaginosis
prospective studies are significantly important for exploring the risk factors of BV during pregnancy. In April 2012, we established a cohort of pregnant women in the Maternal and Child Health Care Hospital of Maanshan, Anhui Province, China. One of the main aims of this prospective study was to examine the incidence and risk factors for BV during pregnancy.
Methods In April 2012, a cohort that was composed of pregnant women who sought prenatal care was established to identify the incidence and potential risk factors of BV during pregnancy. The study protocol was approved by the Research Ethics Committee of the University of Anhui Medical University. Before the study was conducted, the objectives and details of the study were explained to the Maternal and Child Health Care Hospital of Maanshan, to obtain their approval and support. Participating women met the following criteria: (i)
