Long-term risk of hysterectomy and ectopic pregnancy among Vietnamese women using the quinacrine hydrochloride pellet system vs. intrauterine devices or tubal ligation for contraception

Abstract

Objectives: Determine the long-term risk of hysterectomy and ectopic pregnancy in women using the quinacrine hydrochloride pellet system of permanent contraception (QS) relative to the comparable risk in women using Copper T intrauterine device (IUD) or tubal ligation surgery (TL) for long-term or permanent contraception.

Methods: This was a retrospective cohort study, conducted in the Northern Vietnamese provinces of Ha Nam, Nam Dinh, Ninh Binh and Thai Binh. Women who had their first QS procedure, last IUD insertion or TL between 1989 and 1996 were interviewed regarding post-procedure health outcomes approximately 16 years post exposure.

Results: A 95% response rate resulted in 21,040 completed interviews. Overall incidence rates were low for both outcomes (91/100,000 women years of follow-up and 22/100,000 women years of follow-up for hysterectomy and ectopic pregnancy, respectively). After accounting for variations in baseline characteristics between women choosing QS vs. the other two contraceptive methods, no significant excess hazard of either hysterectomy or ectopic pregnancy was associated with QS.

Conclusions: No significant excess long-term risk of hysterectomy or ectopic pregnancy was found among a large group of women using QS vs. IUD or TL for contraception after an average 16 years of follow-up.

Chinese abstract

目的：判定采用盐酸喹吖啶微丸系统永久避孕（QS）的女性出现子宫切除术和异位妊娠的远期风险, 并与用含铜T型宫内节育器（IUD）或输卵管结扎手术（TL）用于长期或永久避孕的女性比较其相对风险。

方法：这是一个在越南北部省份（河南省、南定省、宁平省和太平省）进行的回顾性队列研究。我们随访了从1989年到1996年间第一次进行QS操作, 最后一次放置IUD或TL的女性在暴露后约16年的术后健康结局。

结果：本研究应答率为95%, 共21,040次完整的访视。两个结局总的发病率都很低（随访年份中发生子宫切除术的女性为91/100,000, 发生异位妊娠为22/100,000）。在考虑了选择QS和其他两种避孕方法的女性基线特征的变化后, 子宫切除术或异位妊娠与QS均无显著相关。

结论：在对采用QS或IUD或TL避孕的大样本妇女中, 未发现子宫切除术或异位妊娠更多的远期风险。

Keywords:

• Quinacrine
• retrospective cohort study
• survival analysis
• non-surgical permanent contraception
• female
• hysterectomy
• ectopic pregnancy

Disclosure statement

ISAF had sponsored previous reproductive research in Vietnam and other countries and had an impact on the selection of sites for this study. Originally ISAF hired a Contract Research Organization (CRO) to operationalise the study, and the authors were requested to design the study, design and carry out the analysis, and publish the report. Subsequent to the start of the study, ISAF took over the CRO functions. They also reviewed and provided comments on the study report and draft manuscript.

Notes

1 Women surveyed for this study were part of a large field trial that included more than 1300 clinicians in 24 provinces and resulted in approximately 55,000 QS cases. Most of the 11,105 QS procedures (97.5%) performed in the four provinces included in this study had been completed by the end of 1992, and another 4% (449 cases) in 1993. Although the Vietnamese government halted the trial at the end of 1993 and recalled the small quantities of quinacrine pellets that had not been administered to women, clinic records identified 33 additional procedures performed in these provinces between 1994 and 1996. Based on discussions with the study sponsors, who have extensive history with the reproductive health community in Vietnam, it appears that some physicians in the rural areas kept their remaining small supplies of QS pellets and used them to perform the additional procedures in 1994–1996.

2 International Services Assistance Fund (ISAF), 104 T.W. Alexander Drive, Bldg. 1, Research Triangle Park, NC 27709. 

3 Physicians working at the provincial/district levels of Vietnam’s reproductive health system were trained to conduct all interviews for the survey. Use of physicians as interviewers was intended to enhance women’s comfort levels when discussing their health, and also to make certain that appropriate follow-up questions would be used to ensure that the women surveyed were properly citing cancer diagnoses. In addition, employing physicians trained consistently in interview procedures was also intended to minimise any possible effect on survey results from use of multiple interviewers.

4 This review entailed modelling multiple scenarios that would reveal different biases in all stages of data collection.

Additional information

Funding

This work was supported by the non-profit International Services Assistance Fund (ISAF).