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Continuous oral contraception: changing times.
1Department of Obstetrics and Gynecology, Scott & White Clinic/Memorial Hospital and Texas A & M University System Health Science Center, College of Medicine, Temple, TX, USA. psulak@swmail.sw.org
Best Practice & Research. Clinical Obstetrics & Gynaecology
|September 26, 2007
Summary
Standard oral contraceptives (OCs) with a 7-day hormone-free interval (HFI) can lead to unintended pregnancies and side effects. Modified OC regimens are emerging to improve efficacy and reduce adverse events.
Area of Science:
- Reproductive Health
- Endocrinology
Background:
- Oral contraceptives (OCs) are the most common reversible contraception method.
- The standard 21/7 regimen (21 active pills, 7 placebo) has persisted despite evolving formulations.
- Low-dose OCs with a 7-day hormone-free interval (HFI) present significant drawbacks.
Purpose of the Study:
- To review the scientific data on the disadvantages of standard 21/7 oral contraceptive regimens.
- To discuss modifications in oral contraceptive regimens that address these disadvantages.
- To highlight improvements in efficacy and side-effect profiles with modified regimens.
Main Methods:
- Literature review of studies on oral contraceptive regimens.
- Analysis of data concerning the 7-day hormone-free interval (HFI) in low-dose OCs.
- Evaluation of scientific evidence on the impact of OC regimen modifications.
Main Results:
- The 7-day HFI in low-dose OCs is linked to incomplete pituitary-ovarian suppression.
- This interval can result in follicular development, endogenous estradiol production, and potential ovulation.
- Hormone withdrawal symptoms during the HFI contribute to OC discontinuation and increased risk of unintended pregnancy.
Conclusions:
- The standard 21/7 oral contraceptive regimen requires modification due to documented disadvantages.
- Emerging modified OC regimens aim to enhance contraceptive efficacy and improve tolerability.
- Scientific data supports the need for revised OC dosing strategies to optimize reproductive health outcomes.
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