Yunnan Institute of Population and Family Planning Research, Kunming, China 4

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1 517259APH / Asia-Pacific Journal of Public HealthZhou et al research-article2014 Article Temporal Trends of Copper-Bearing Intrauterine Device Discontinuation: A Population-Based Birth-Cohort Study of Contraceptive Use Among Rural Married Women in China Asia-Pacific Journal of Public Health 2015, Vol. 27(2) APJPH Reprints and permissions: sagepub.com/journalspermissions.nav DOI: / aph.sagepub.com Jie Zhou, MMed 1,2, Xiaodong Tan, PhD 1, Xiangjing Song, MD 3, Kaining Zhang, MMed 2, Jing Fang, PhD 2, Lin Peng, MMed 3, Wencai Qi, MD 4, Zonghui Nie, MD 5, Ming Li, MD 6, Rui Deng, MMed 2, and Chaofang Yan, MMed 2 Abstract Copper-bearing intrauterine device (IUD) insertion for long-term contraceptive use is high in China, but there has been evidence that first-year discontinuation rate of copper-bearing IUD has also increased rapidly in recent years especially among rural married women. To investigate long-term use of copper-bearing IUD, the authors examined the 7-year temporal trends of copper-bearing IUD discontinuation in a population-based birth-cohort study among 720 rural married women in China, from 2004 to Women requesting contraception were followed-up twice per year after the insertion of IUD. The gross cumulative life table discontinuation rates were calculated for each of the main reasons for discontinuation as well as for all reasons combined. By the end of 7 years, 384 discontinuations were observed. With a stepped-up trend, the gross cumulative life table rate for discontinuation increased from (95% confidence interval = ) per 100 women by the first year to (95% confidence interval = ) per 100 women by the end of 7 years, which increased rapidly in the first 2 years after copper-bearing IUD insertion, flattened out gradually in the following 2 years, then increased again in the last 3 years. Among reported method failure, expulsion and side effects were the main reasons for discontinuation of the copper-bearing IUD but not pregnancy. Personal reasons, such as renewal by personal will had influenced copperbearing IUD use since the second year and should not be neglected. Based on this study, the temporal trends of copper-bearing IUD discontinuation was in a stepped-up trend in 7 years 1 Wuhan University, Wuhan, China 2 Kunming Medical University, Kunming, China 3 Yunnan Institute of Population and Family Planning Research, Kunming, China 4 Family Planning Centre of Yuanmou County in Yunnan Province, Yuanmou, China 5 Health Bureau of Yuanmou County, Yuanmou, China 6 Maternal and Child Care Service Centre of Yuanmou County, Yuanmou, China Corresponding Author: Jie Zhou, MMed, School of Public Health, Wuhan University, Wuhan, , China @163.com

2 NP2434 Asia-Pacific Journal of Public Health 27(2) after insertion. Both reported method failure (expulsion and side effect) and personal reason had effect on the discontinuation of copper-bearing IUD, but pregnancy was no more the most important reason affecting the use of copper-bearing IUD. Keywords copper-bearing intrauterine device, discontinuation, temporal trends, life table rates Introduction The intrauterine device (IUD) is one of the most widely used, reversible contraceptive methods in the world, and women living in China constitute about 70% of the 106 million global users. 1 As a long-lasting, flexible, safe, and reversible method, IUD is currently the most popular method of birth control in China, used by more than 40% of women of reproductive age in rural areas. 2,3 Previously, the most commonly used IUD in China was the stainless steel ring (SSR), which has been available since the 1950s. 4 With the introduction of the copper-bearing IUD in the early 1980s, together with evidence from many comparative studies that the SSR had much higher failure and expulsion rates, 5,6 the State Family Planning Commission decided to stop producing the SSR in The copper-bearing IUD had a long life span, for example, a copper T IUD continued to be effective for up to 20 years. 8 Copper-bearing IUD insertion for long-term use is high in China, but recently there has been evidence that copper-bearing IUD failure rate in China was also among the highest, and it has been shown that the first-year discontinuation rate for IUD was nearly 10%. 9,10 Since gynecologists practicing in China are seeing an increasing number of long-term copper-bearing IUD use, it is essential to explore the temporal tends of copper-bearing IUD discontinuation. The present study serves to provide a population-based temporal trend in the rates of copperbearing IUD discontinuation among rural married women from 2004 to 2012 in Yuanmou county of Yunnan, one of China s most populous provinces. The objectives of this study were 3-fold: (a) to investigate the temporal trend of copper-bearing IUD discontinuation as contraceptive use among rural married women for up to 7 years after insertion, (b) to investigate the continuation rate for up to 7 years of use, and (c) to determine the reason of copper-bearing IUD discontinuation for up to 7 years postinsertion. Methods Study Population and Recruitment This prospective population-based birth-cohort study was conducted by Kunming Medical University and family planning clinics in Yuanmou County of Yunnan province, China. Eligible participants were healthy rural married women, aged 18 to 45 years, with regular menstrual cycles between 24 and 42 days duration and a known date of the last menstrual period (LMP). Women needed to have a desire to use IUD as a long-term contraceptive method, accepted a copper-bearing IUD insertion from July 1, 2004 to June 30, 2005 in family planning clinics and hospital, and also were willing to participate in 2-times-per-year follow-up examination. Exclusion criteria included suspected or confirmed pregnancy, any episode of pelvic inflammatory or pelvic abscess in the 12 months preceding trial admission, sexually transmitted infection within the past 6 months, any evidence of sexually transmitted infection on clinical or laboratory examination during the initial examination, multiple sexual partners, known or suspected genital tract malignancy, cervical or uterine malformations, vaginal bleeding of unknown etiology, and multiple uterine fibroids associated with previous menstrual anomalies. In addition, women who were unsure about the date of their LMP (LMP needed for pregnancy risk assessment), were currently

3 Zhou et al NP2435 taking oral contraceptive pills, or had used spermicide, condom (even in cases of slippage or breakage), or other barrier method during their last sexual intercourse were excluded from the study. All women who satisfied the admission criteria gave written informed consent and were subsequently enrolled into the study. Women were asked to come for follow-up visits 2 times per year from 2005 to Women were also instructed to return for unscheduled visits if they had any problems. The clinics participating in this trial were open from Monday to Saturday, and acute care clinics were open in the evenings and at weekends, should an unscheduled visit be necessary. The copper-bearing IUDs used in this trial were all provided by the government, produced by certified enterprises/factories in China. China Food and Drug Administration had approved these copper-bearing IUDs. The validity periods of copper-bearing IUDs were more than 7 years. Details of Ethics Approval Ethics approval was given by the Institutional Review Board of the National Research Institute for Family Planning, Beijing. Written informed consent was obtained from all women participating in the study. Sampling Procedure The sample was based on a national cross-sectional survey of copper-bearing IUD use among rural married women in China. The multiphase stratified random cluster sampling method was applied in 4 major steps. First of all, Yunnan Province was randomly selected from the western provinces of China. Second, Yuanmou County was 1 of the 3 counties that was randomly selected from Yunnan Province. Third, in Yuanmou County, 3 townships were selected for the study. The central township, which is the official seat of a county government, and the remaining 2 were randomly sampled from the total number of townships in the country. Finally, based on the daily record of the prevalence of contraceptive use among women, at least 200 eligible women from each selected township were cluster sampled from the village. To take into account an estimated 20% refusal or loss to follow-up, 240 target women from each study site were initially randomly sampled. Follow-up Visits The initial visit included the recording of information regarding the date of the initial examination, age, medication use; date of onset of LMP, usual cycle length, and expected date of onset of next menstruation; and contraceptive history, including the use of contraception during the previous and current cycle. A pelvic examination was performed to determine whether there was any evidence of cervical or uterine infection. The follow-up visits were based on the daily clinical visit by the family planning administration and the information was taken from the medical record. Women could discontinue the study early at any time. Investigators discontinued any participation in cases of pelvic inflammatory disease, perforation, copper-bearing IUD displacement or expulsion, pregnancy, or high-grade cytological findings on the Papanicolaou screening test. In cases of pain, irregular bleeding, or heavy menstruation, the woman and the physician investigator could decide whether or not to continue the trial. Nonmedical reasons for discontinuation included failure to rely solely on copper-bearing IUD as a method of contraception, desire to become pregnant, a move out of the study area, and loss to follow-up. Measures The primary outcome measures were the gross cumulative life table discontinuation rates for each of the main reasons (reported method failure and personal reason) in every year. These were

4 NP2436 Asia-Pacific Journal of Public Health 27(2) determined by a positive high-sensitivity urine pregnancy test, by vaginal/abdominal ultrasound, and/or by personal report at the follow-up visit. Secondary outcome measures included cumulative life table continuation rates from up to 7 years after insertion. Analysis The data were collected on standard precoded duplicate forms at admission, follow-up, and final visits at the family planning clinic. The forms were sent to the Institute of Health Sciences of Kunming Medical University in Kunming, which was the coordinating centre responsible for the data management of the trial. The data were analyzed on a personal computer with the Statistical Package of Life Table Analysis (LTA, World Health Organization, Geneva, Switzerland). 11 Single decrement, gross cumulative life table discontinuation rates were calculated for each of the 3 main reasons (reported method failure, a desire to become pregnant, and personal reason) for annual discontinuation as well as for all reasons combined. Every year, gross cumulative life table discontinuation rates were computed with the corresponding 95% confidence interval. Results Demographics and Clinical Characteristics of Intrauterine Device Use After all inclusion/exclusion criteria were applied, a total of 720 women participated in the study between July 1, 2004 to June 30, 2005 in family planning institutions, clinics, or hospitals in 3 towns throughout Yuanmou County. Participants lost to follow-up before 7 years were included in the analysis up to the point when they were lost to follow-up. The baseline characteristics of these participants based on parity are shown in Table 1. The majority of copper-bearing IUD users had at least a secondary school education (53.75%). The outcome of the last pregnancy for most women users was vaginal delivery (74.03%), followed by induced abortion (13.99%) and abdominal delivery (9.16%). For nearly 50% of the participants, it was their first time to have copper-bearing IUD insertion, but more than 40% of the women had a second insertion and nearly 10% had 3 or more insertions. The 3 major types of copper-bearing IUD used by the women in this study were uterine-shaped Cu (32.08%), T Cu (21.67%), and active γ (20.56%). Discontinuation of Copper-Bearing Intrauterine Device by the End of 7 Years By the end of 7 years, 384 discontinuations had occurred. The main reasons for these discontinuations were as follows: reported method failure (184; including 115, 43, and 26 for expulsion, removals for bleeding/pain, and pregnancy, respectively), planning pregnancy (141), and renewal by personal will (59). In addition, 40.14% of the women were continuing copper-bearing IUD users at the end of 7 years, and 6.53% (47 cases) were not followed for a complete 7 years because of loss to follow-up (23) and because of the cutoff date of the study (study termination 24). Temporal Trends of 7 Years Copper-Bearing Intrauterine Device Discontinuation and Continuation The gross cumulative life table discontinuation rates are shown in Figure 1. These rates were calculated for each of the 2 main reasons (reported method failure, planning pregnancy, and renewal by personal will) for every year discontinuation as well as for all reasons combined. The gross cumulative discontinuation rates was (95% confidence interval [CI] = ) per 100 women in the first year. As with previous studies, rate of discontinuation was high

5 Zhou et al NP2437 Table 1. Baseline Demographics and Clinical Characteristics of the Copper-Bearing Intrauterine Device (IUD) Users Enrolled in the Study. a Participant Characteristics and History of IUD Use Total (N = 720) Age in years, mean ± SD ± 4.76 Education, n (%) Illiterate 2 (0.28) Primary 290 (40.28) Secondary 387 (53.75) High school 40 (5.55) College and above 1 (0.14) Result of the last pregnancy, n (%) Vaginal delivery 533 (74.03) Abdominal delivery 66 (9.16) Abortion 6 (0.83) Induced abortion 100 (13.90) Dislocated pregnancy 8 (1.11) Other 7 (0.97) History of IUD use, n (%) 1 time 339 (47.08) 2 times 302 (41.95) 3 times 73 (10.14) >3 times 6 (0.83) IUD type at present, n (%) Uterine-shaped Cu 231 (32.08) T Cu 156 (21.67) Active γ 148 (20.56) MLCu (8.19) AiMu MCu 61 (8.47) Ring Cu 39 (5.42) Other 26 (3.61) in the first year after insertion. But it was observed that the rate showed an upward trend in following years by this study. At the first 2 years, the gross cumulative discontinuation rates increased from (95% CI = ) per 100 women to (95% CI = ) per 100 women, in a gradually increasing trend. Then, it rose at a slower pace, just (95% CI = ) per 100 women for the third year and (95% CI = ) per 100 women for the fourth year. After that, it increased rapidly again; gross cumulative discontinuation rates for the fifth, the sixth, and the seventh year were (95% CI = ) per 100 women, (95% CI = ) per 100 women, and (95% CI = ) per 100 women, respectively. And the cumulative continuation rates were (95% CI = ) per 100 women at the end of 7 years; the rates for other years are shown in Table 2. The Main Reasons for Discontinuation All the reported reasons method failure, planning pregnancy, and renewal by personal will contributed to the gross discontinuation. But each of them had different temporal trends and contributed to the gross discontinuation in different period (shown in Figure 1). The cumulative rates of reported method failure were (95% CI = ) per 100 women and (95% CI = ) per 100 women in the first and the second year with a gradually

6 NP2438 Asia-Pacific Journal of Public Health 27(2) Figure 1. The cumulative discontinuation rate in 7 years. Table 2. Gross Cumulative 7 Years Continuation/Discontinuation Rates for IUD by Reason for Discontinuation per 100 Women. Reasons for Discontinuation Year Continuation (CI) All Reasons (CI) Reported Method Failure (CI) Planning Pregnancy (CI) Personal Reasons (CI) ( ) ( ) ( ) ( ) ( ) ( ) 0.52 ( ) 0.18 (0-0.52) ( ) ( ) ( ) 3.61 ( ) 0.18 (0-0.52) ( ) ( ) ( ) ( ) 1.16 ( ) ( ) ( ) ( ) ( ) 4.44 ( ) ( ) ( ) ( ) ( ) 7.48 ( ) ( ) ( ) ( ) ( ) ( ) Abbreviations: IUD, intrauterine device; CI, confidence interval. increasing trend, but it flattened out gradually from third year after copper-bearing IUD insertion. From the third to the seventh year, the cumulative failure rates of copper-bearing IUD only increased from (95% CI = ) per 100 women to (95% CI = ) per 100 women with a slow upward trend in 5 years. The cumulative rates of planning pregnancy and renewal by personal will were similar to each other. Neither planned pregnancy nor renewal by personal will occurred in the first year, but both of them appeared from the second year. The cumulative rates of planning pregnancy increased rapidly in the following years, from 0.52 (95% CI = ) per 100 women in the second year to (95% CI = ) per 100 women in the seventh year, which was extremely close to cumulative rates of IUD failure. The cumulative rates of renewal by personal will was at a low level until the fourth year, from 0.18 (95% CI = ) per 100 women to 1.16 (95% CI, ) per 100 women, and then increased in the last 3 years to reach (95% CI = ) per 100 women in the seventh year. The reported method failure included pregnancy, expulsion, and removal due to bleeding/ pain. Compared with other reasons, the cumulative rate for pregnancy was the lowest among 7 years and never more than 5 per 100 women (Figure 2). Expulsion was the most important reason for the reported method failure. The cumulative rates of expulsion soared in the first 2 years, 7.07

7 Zhou et al NP2439 Figure 2. The cumulative rate of intrauterine device failure in 7 years. (95% CI = ) per 100 women for the first year and (95% CI = ) per 100 women for the second year, and then it flattened out gradually since the third year. At the end of 7 years, it was up to (95% CI = ). Both the cumulative rates of pregnancy and removals due to bleeding/pain showed a slow rise. At first, the cumulative rate of pregnancy was higher than that of the removals due to bleeding/pain. And then, after 4 years, the cumulative rate of the removals due to bleeding/pain was higher than that of pregnancy. At the end of 7 years, the cumulative rate of pregnancy and removals due to bleeding/pain were up to 4.84 (95% CI = ) per 100 women and 6.27 (95% CI = ). Pregnancy was no more the most important reason of IUD failure. Discussion This study may be the first prospective population-based birth-cohort study to report the discontinuation of the copper-bearing IUD among married women in the rural area of China by following-up for 7 years. In addition, this study reports the gross cumulative life table rates for each of the 3 main reasons for every year discontinuation as well as for all reasons combined. The stepped-up trend of copper-bearing IUD discontinuation presented in this report was different from those reported in previous multicenter trials 12,13 and very few reported in more recent studies of IUDs, especially in China. The temporal trend of copper-bearing IUD discontinuation can be identified into 3 stages. First of all, in the first 2 years, the gross cumulative discontinuation rates increased in a gradually trend, reaching nearly 20 per 100 women in the end. As with previous and recent studies, 9,14-17 rates of discontinuation were high in the first 2 years after insertion. But in this population-based study, the rates of the first year caught up with the rates of second year in clinic-based study in the same period. However, all these studies indicate that early discontinuation of copper-bearing IUD use continues to be an important problem. Second, in the third and fourth years, the rates flattened out gradually. And it seems that the copperbearing IUD use implied satisfaction with the method. But after that, third, the rates increased rapidly again until the end of 7 years, which has seldom been reported in previous studies. In addition, compared with the previous study in China, 12 the cumulative continuation rate of copper-bearing IUD decreased faster than before. Our findings suggest that the temporal trend of copper-bearing IUD discontinuation has changed and has different characteristics in different period and women should receive counseling from family planning doctor and researchers with a focus on certain problems associated with IUD use.

8 NP2440 Asia-Pacific Journal of Public Health 27(2) Among these 3 reasons of copper-bearing IUD discontinuation, the reported method failure (including expulsion, removals due to bleeding/pain, and pregnancy) was often reported by other studies. 12,13,18 But neither planning pregnancy nor renewal by personal will was mentioned in recent studies, especially in China. Compared with the previous study, both the rates of planning pregnancy and personal reason were higher than those reported in Although we cannot show causality, the clear association of the increase in discontinuation rates with planned pregnancy and renewal by personal will of the copper-bearing IUD since the third year suggests that personal reasons were responsible for the increase of the discontinuation rate. Personal reasons had been reported by Rivera et al 20 in 1999, but this study only focused on planned pregnancy. In this study, we found that renewal of copper-bearing IUD by personal will since the second year would affect the formal use of copper-bearing IUD more and more significantly. The life span of copper-bearing IUD is reported more than 10 years, and it has a good overall performance and a longer life span than previously expected. 21 But renewal of copperbearing IUD by personal will occurred since the second year after the insertion, and was up to (95% CI = ) per 100 women in the seventh year. However, all previous copperbearing IUD studies indicate that early discontinuation (the first year after copper-bearing IUD insertion) of copper-bearing IUD use continues to be an important problem. Compared with women who continued use of copper-bearing IUD, the women who renewed copper-bearing IUD by personal will would face the same problem twice or more during the same period. Although reasons for variation in the willingness or ability of women to persist with this method are unclear, the reasons for discontinuation of copper-bearing IUD were not related to the method itself but were driven by user and family planning doctors. It suggests that personal reason had influenced copper-bearing IUD use seriously and should not be neglected in the future. Figure 1 displays the cumulative discontinuation rates of copper-bearing IUD use per 100 women due to these main reasons from 1 to 7 years after insertion. The top 3 failure outcomes included total failure of copper-bearing IUD use, planned pregnancy, and renewal by personal will. Furthermore, rate of expulsion was increased significantly. Actually, expulsion is not a medical complication caused by method itself. Other studies conducted in China revealed that expulsion rates vary from 0.7 to 6.4 in the first year of copper-bearing IUD use, which were similar to the results of this study. Some studies reported that expulsion was more likely to happen among young women and the women who have not had children. 25,26 and the people in the study were married but 40% of them were younger than 25 years. Proper performance and skill of providers at placement of copper-bearing IUD in the uterine cavity has been shown to be associated with failure of copper-bearing IUD use. 27 If providers have not correctly placed a copperbearing IUD up to the top of the uterus, expulsion and downward dislocation can occur. This indicates that providers should be able to carefully measure position and size of the uterine cavity, and also choose a matched size of copper-bearing IUD for clients. During the study period, there were more than 10 types of copper-bearing IUD in Yuanmou County, but many providers reported that only 1 or 2 sizes of IUD for each type were available. Therefore, improper choice of copper-bearing IUD size may be an important contributing factor that can lead to the high rate of copper-bearing IUD expulsion. This study suggests that more studies focusing on the expulsion of copper-bearing IUD are needed in the future. Although this study demonstrates the efficacy of copper-bearing IUD, it is not without limitations. This was an observational study, and thus participants were not randomized to the type of copper-bearing IUD. Second, the main limitations of this analysis stem from the narrow range of available data. The birth cohort came from only single one county. Third, we did not perform any statistical tests among the different type of copper-bearing IUD because there were significantly more than 10 types of copper-bearing IUD enrolled in this study, making statistical tests among these groups difficult. This report therefore provides a general sense of how rural married women tolerate copper-bearing IUD as a long-term contraceptive.

9 Zhou et al NP2441 Conclusion Based on this study, the temporal trend of copper-bearing IUD discontinuation was in a steppedup manner over 7 years after insertion. The gross cumulative life table discontinuation rates for each of the 3 main reasons (reported method failure, a desire to become pregnant, and personal reason) as well as for all reasons combined had all increased for the long time use. Both reported method failure (expulsion and side effect) and personal reason had an effect on the discontinuation of copper-bearing IUD, but pregnancy was no more the most important reason that affected the use of copper-bearing IUD. Acknowledgments We acknowledge the diligent work of all family planning service providers who completed the follow-up visit in 7 years and collected data in the field. We thank Drs Junjie Li, Hao Luo, and Dong Jun for their invaluable expertise on clinical operation of intrauterine device insertion and data analyses. Last but not least, we appreciate the time and support of all participants. Declaration of Conflicting Interests The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Funding The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This study was funded by the National Research Program for the Tenth Five-Year Plan on Science and Technology (No. 2004BA720A31) and the Research Program of Scientific Research Funds of Education Department of Yunnan Province (No. 2010Y209). References 1. Ali MM, Sadler RK, Cleland J, Ngo TD, Shah IH. Long-Term Contraceptive Protection, Discontinuation and Switching Behaviour: Intrauterine Device (IUD) Use Dynamics in 14 Developing Countries. London, England: World Health Organization and Marie Stopes International; Bilian X. Chinese experience with intrauterine devices. Contraception. 2007;75(6 suppl):s31-s Gupta S, Kirkman R. Intrauterine devices update on clinical performance. Obstet Gynaecol. 2002;4: MacDonald TL, Gerscovich EO, McGahan JP, Fogata M. The Chinese ring: a contraceptive intrauterine device. J Ultrasound Med. 2006;25: State Family Planning Commission of China. A Clinical Trial of Three Commonly Used IUDs. Condensed Summary of Family Planning Scientific Research Results During the Sixth Five-Year Plan. Beijing, China: State Family Planning Commission of China; Gao J, Shen H, Zheng S, et al. A randomized comparative clinical evaluation of the steel ring, the VCu200 and the TCu220c IUDs. Contraception. 1986;33: Khanna J, Maurice J, eds. WHO HRP Department of Reproductive Health and Research China to upgrade its IUD technology. Prog Reprod Health Res. 2002;60: Sivin I. Utility and drawbacks of continuous use of a copper T IUD for 20 years. Contraception. 2007;75(6 suppl):s70 S Zhang A, Wang A, Lai Y. Study on active γ type II intrauterine device. Chin J Fam Plann. 2011;19: Zhang KN, Wu SC, Peng L, et al. Epidemiologic study on IUD use and failure in nine provinces of China. Chin J Fam Plann. 2007;11: LTA Survival Analysis. Geneva, Switzerland: World Health Organization; Fang K, Chen J, Wu M, et al. Comparison of the performances of three type of IUD up to eight years. Chin J Fam Plann. 1994;9:19-61.

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