Abstract
The purpose of this integrative literature review was to appraise studies conducted worldwide using misoprostol and estradiol in converting Type 3 transformation zone (TZ) of the cervix into Types 1 or 2 and to assess which regimen could be more feasible in low-and-middle-income countries (LMICs). We reviewed the English language literature for peer-reviewed studies that evaluated strategies to convert Type 3 TZs to Types 1 or 2 for cervical cancer screening. Web of Science and PubMed searches were performed up to July 2020. Search terms included: "cervical colposcopy," "inadequate colposcopy", "cervical cancer screening", "transformation zone," "estrogen", "estradiol", and "misoprostol." Inclusion criteria were articles published in the English language, original research, and peer reviewed articles. A total of 127 articles were abstracted, 24 articles were reviewed, and 9 articles met all inclusion criteria. We found that intravaginal misoprostol, intravaginal estradiol, and oral estradiol can successfully convert Type 3 TZ to Types 1 or 2. A single dose of vaginal misoprostol had a similar maximum response rate (20-80%) to a multi-dose regimen over several days or weeks of both intravaginal estradiol (64-83%) and oral estradiol (50-70%). Misoprostol administration was associated with more side effects such as abdominal cramping and vaginal bleeding compared to estradiol, although these were generally mild. In conclusion, Oral estradiol, intravaginal estradiol, and intravaginal misoprostol can be used to convert Type 3 TZ to Types 1 or 2. Intravaginal misoprostol is well tolerated and more feasible in LMICs due to availability and shorter treatment schedule compared to oral or intravaginal estradiol.