title: The risk of using intrauterine devices to benign reproductive system conditions in postmenopausal women: A case control study.
abstract: BACKGROUND
  To investigate the effect of using intrauterine devices (IUDs) during the fertile window on women's reproductive system health.
  
  
  METHODS
  2,744 postmenopausal women in the Minhang District, Shanghai, China were enrolled. In the IUDs group there were 2,253 women; in the tubal ligation group there were 202 women and there were 289 women in the control group. We selected subjects according to the cases number in different hospital by using step sampling, and, in addition, collected the sociological data and information of the previously used contraceptives by the subjects, which included whether the contraceptives were used appropriately and the effect they had. Kolmogorov-Smirnov test, Levene's test, and logistic regression analysis were used to analyze the data.
  
  
  RESULTS
  The prevalence rate of benign reproductive system conditions was significantly different among them (P< 0.05). Further comparison revealed, the rate in Group 1 was significantly lower than that in Group 2 and Group 3 (P< 0.05, respectively). Results of logistic regression analysis show that the risk factors for development of such conditions lie in the women's pregnancy history [odds ratio (OR) = 3.85], reproductive history (OR = 0.5), the use of IUD in fertile window (OR = 0.4), tubal ligation (OR = 1.74), birth control time (OR = 0.9), contraceptive failure history (OR = 1.7), and history of family planning procedures (OR = 1.73).
  
  
  CONCLUSIONS
  IUDs, maybe, can effectively reduce the risk of getting benign reproductive conditions in postmenopausal females.
authors.affiliation: Department of Obstetrics and Gynecology, Maternal and Child Health Hospital, Minhang, China.
authors.forename: Xiaohua
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Obstetrics and Gynecology, Maternal and Child Health Hospital, Minhang, China.
authors.forename: Liping
authors.initials: L
authors.lastname: Xiao
authors.affiliation: Department of the Basic Medical Research Center, Shanghai Institute of Planned Parenthood, Shanghai, China.
authors.forename: Haoping
authors.initials: H
authors.lastname: Zhu
authors.affiliation: Department of the Basic Medical Research Center, Shanghai Institute of Planned Parenthood, Shanghai, China.
authors.forename: Linan
authors.initials: L
authors.lastname: Cheng
keywords: Benign reproductive system; contraception; fertile window; intrauterine devices (IUDs)