宫内节育器（IUD）是最有效的避孕方法之一。在过去的二十年里，美国使用IUD的数量有所增加。美国有两种商用配方：左炔诺孕酮缓释宫内节育器（LNG-IUD）和铜宫内节育器（Cu-IUD）。LNG-IUD释放孕激素，引起子宫内膜抑制和宫颈粘液增稠，而Cu-IUD的主要机制是形成局部炎症反应防止受孕。虽然联合荷尔蒙避孕对卵巢和子宫内膜癌以及输卵管结扎和卵巢癌的保护作用被普遍接受，但对现代IUD对妇科恶性肿瘤发展的影响了解较少。关于IUD使用对于LNG-IUD和子宫内膜癌的保护作用，有最可靠的证据，尽管研究表明，Cu-IUD和LNG-IUD都可以减少子宫内膜癌的风险。这得到了双重作用机制的支持，包括子宫内膜抑制和局部炎症反应。关于IUD使用与卵巢癌风险之间的关系的研究结果存在冲突，尽管数据的多数倾向于IUD用户卵巢癌风险降低。针对降低卵巢癌风险的拟议生物学机制（异物体炎症反应，pH 值增加，抗雌激素作用，抑制排卵等）因IUD类型而异。虽然铜宫内节育器使用可以降低宫颈上皮内瘤样病变的风险，但LNG-IUD使用对宫颈癌的影响仍不清楚。旧研究将其使用与更高的宫颈上皮内瘤样病变发病率联系起来，但更近期的文献发现宫内节育器使用可以减少宫颈癌的发生率。提出了各种保护机制，包括内宫颈管器械相关的炎症反应和前列腺素介导的免疫监视。总体而言，现有证据表明LNG-IUD和Cu-IUD均可降低妇科癌症的风险。尽管有支持使用激素和Cu-IUD降低子宫内膜癌风险以及使用Cu-IUD降低宫颈癌风险的证据，但LNG-IUD在降低宫颈癌和卵巢癌风险方面的证据不一致。版权所有© 2023 Elsevier Inc.。

The intrauterine device (IUD) is one of the most effective forms of contraception. Use of the IUD has increased in the United States (US) over the last two decades. Two formulations are commercially available in the US: the levonorgestrel-releasing intrauterine device (LNG-IUD) and the copper IUD (Cu-IUD). The LNG-IUD releases progestin causing endometrial suppression and cervical mucus thickening, while the primary mechanism of action of the Cu-IUD is to create a local inflammatory response to prevent fertilization. While the protective effects of combined hormonal contraception on ovarian and endometrial cancer and tubal sterilization and ovarian cancer are generally accepted, less is known about the effects of modern IUDs on the development of gynecologic malignancies. The best evidence for a protective effect of IUD use on cancer incidence exists for LNG-IUD and endometrial cancer, though studies suggest that both the Cu-IUD and LNG-IUD reduce endometrial cancer risk. This is supported by proposed dual mechanisms of action including both endometrial suppression and a local inflammatory response. Studies of the relationship between IUD usage and ovarian cancer risk show conflicting results, although the preponderance of the data is toward reduced risk of ovarian cancer in IUD users. Proposed biological mechanisms of ovarian cancer reduction (foreign body inflammatory response, increased pH, anti-estrogenic effect, ovulation suppression) vary based on type of IUD. While it has been well established that the use of Cu-IUD confers a lower risk of cervical intraepithelial neoplasms, the use of LNG-IUD and its effect on cervical cancer remains unclear. Older studies have linked its use to a higher incidence of cervical dysplasia, but more recent literature has found a decrease in cervical cancer with IUD use. Various mechanisms of protection are postulated including device-related inflammatory response in the endocervical canal and prostaglandin mediated immunosurveillance. Overall, the available evidence suggests that both LNG- and Cu-IUDs reduce gynecologic cancer risk. While there is support for the reduction of endometrial cancer risk with hormonal and Cu-IUD use, and reduction of cervical cancer risk with Cu-IUD use, evidence in support of risk reduction with LNG-IUD use for cervical and ovarian cancers is less consistent.Copyright © 2023 Elsevier Inc. All rights reserved.