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Updated: Jun 8, 2026

Fertility Preservation Through Oocyte Vitrification: Clinical and Laboratory Perspectives
Published on: September 16, 2021
[Combined hormonal contraception in cycles artificially extended]
Edgardo Bustillos-Alamilla1, J Zepeda-Zaragoza, M A Hernández-Ruiz
1Servicio de Ginecología, Hospital Central Norte PEMEX.
Objective:
To compare the bleeding patterns, satisfaction and tolerability of 3 different contraceptive in an extended regimens in the service of Family Planning of the North Central Hospital of PEMEX.
Material And Methods:
Healthy, adult women with desire of contraception for one year (N 120) were randomly assigned to receive oral contraceptive drospirenone/ethinyl E2 (group1), the norelgestromin/ethinyl E2 transdermal patch (group 2) and vaginal ring etonogestrel/ ethinyl E2 (group 3) in an extended regimen (42 consecutive days, 1 hormone-free week). Study assessments were conducted at scheduled visits at the time of initial screening, at baseline after 1, 3, 6, and 12 months. Subjects recorded menstrual associated symptoms bleeding data and completed satisfaction questionnaires. Subjects and investigators provided overall assessments of the regimens.
Results:
Extended use of 3 different contraceptive resulted in fewer bleeding days in every group (66.6%, 55% and 58.3% P 0.0024), and less mastalgia and menstrual pain. Subjects were highly satisfied with three regimens (93.3%, 96.6% and 91.6% P 0.00421). Although not mayor adverse events were reported with this regimen, there was an increase in spotting days; it decreased with each successive cycle of therapy. Efficacy and safety were similar to those reported for traditional cycle.
Conclusion:
Extended-contraceptive regimen delays menses and reduces bleeding, a profile that may be preferred by women who seek flexibility with their contraceptive method.
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