University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA.
Contraception. 2011 Nov;84(5):e5-e10. doi: 10.1016/j.contraception.2011.05.010. Epub 2011 Jun 30.
Intrauterine devices are cost-effective if used for 2 or more years. Early discontinuation may lead to reduced cost-effectiveness of this method and unintended pregnancy if other contraceptives are not used. This study sought to examine rates and reasons for discontinuation of IUS use in adolescents versus older women and nulliparous versus parous women, as these groups may be more likely to discontinue use.
Retrospective cohort study of women receiving a levonorgestrel IUS between June 2005 and April 2008 was conducted. Medical records were reviewed for all visits following placement of the IUS; rates and reasons for IUS discontinuation were calculated and categorized. Data were examined under two scenarios: (1) assuming that all women not seen for follow-up continued IUS use and (2) only including women with follow-up visits. Cox regression was used to control for age, parity, race and marital status in comparing rates of IUS discontinuation and expulsion in nulliparous versus parous women and adolescents versus older women.
Of the 828 women included in this analysis, 104 (12.6%) were nulliparous, and 131 (15.8%) were ≤20 years of age. Nulliparous women were not more likely than parous women to have expelled their IUS [hazard ratio (95% confidence interval), 1.40 (0.57, 3.43)]. Adolescent women were more likely to experience expulsion than older women, although this did not reach statistical significance [hazard ratio, 1.49 (0.76, 2.92)]. When we looked at reasons for IUS removal, we found that nulliparous women were not more likely than parous women to have their IUS removed because of dissatisfaction with the contraceptive method (6.7% vs. 11.5%, p=.15) or desire to become pregnant (1.9% vs. 2.6%, p=.50). Similarly, adolescents were not more likely than older women to have their IUS removed because of dissatisfaction with the contraceptive method (10.7% vs. 10.9%, p=.94) or desire to become pregnant (3.1% vs. 2.4%, p=.43).
Adolescents and nulliparous women are not more likely to prematurely discontinue use of their IUS than adult or parous women.
如果宫内节育器的使用时间达到 2 年或以上，那么其成本效益是可观的。如果不使用其他避孕措施，早期停止使用宫内节育器可能会降低这种方法的成本效益，并导致意外怀孕。本研究旨在检查青少年和老年妇女、未产妇和经产妇使用宫内节育器的停药率和停药原因，因为这些人群可能更容易停止使用宫内节育器。
对 2005 年 6 月至 2008 年 4 月期间使用左炔诺孕酮宫内节育器的妇女进行了回顾性队列研究。对放置宫内节育器后的所有随访进行了病历回顾；计算并分类了宫内节育器停药率和停药原因。数据在两种情况下进行了检查：（1）假设所有未接受随访的妇女继续使用宫内节育器；（2）仅包括有随访就诊的妇女。在比较未产妇和经产妇以及青少年和老年妇女的宫内节育器停药和脱落率时，使用 Cox 回归控制了年龄、产次、种族和婚姻状况。
在本分析中纳入的 828 名妇女中，有 104 名（12.6%）为未产妇，有 131 名（15.8%）年龄≤20 岁。未产妇的宫内节育器脱落率并不高于经产妇[风险比（95%置信区间），1.40（0.57，3.43）]。与老年妇女相比，青少年妇女更有可能经历宫内节育器脱落，但这并未达到统计学意义[风险比，1.49（0.76，2.92）]。当我们观察宫内节育器取出的原因时，我们发现未产妇因对避孕方法不满意（6.7%对 11.5%，p=0.15）或希望怀孕（1.9%对 2.6%，p=0.50）而取出宫内节育器的可能性并不高于经产妇。同样，青少年因对避孕方法不满意（10.7%对 10.9%，p=0.94）或希望怀孕（3.1%对 2.4%，p=0.43）而取出宫内节育器的可能性并不高于老年妇女。
青少年和未产妇与成年或经产妇相比，提前停止使用宫内节育器的可能性并不更高。
