The use of triphasic oral contraceptives in a continuous use regimen

The objective of this study was to describe the characteristics of and outcomes and side effects in patients using triphasic oral contraceptives (OCs) in a continuous use regimen.

A retrospective review of patient charts from four community-based physician practices was conducted. All patients had been using triphasic OCs in a continuous regimen (i.e., to prevent withdrawal bleeding) for a planned duration of at least three 28-day cycles. Data collected through retrospective chart abstraction included demographic and clinical indicators, duration of and reason for continuous triphasic OC use, prior OC history and side effect incidence and treatment.

Forty-three patients meeting the inclusion criteria had data of sufficient quality to be included in all analyses. These patients represented 603 total cycles. Nearly half of the patients (49%) indicated that their primary reason for continuous OC use was personal preference rather than medical reasons. More than half of the patients (56%) had previously used triphasic OCs in a noncontinuous regimen; 24% had no prior OC experience. The median duration of continuous use was 237 days (including right-censored patients; range, 55-994). Of the 39% of patients who terminated continuous use, the most common reason given was the desire to become pregnant (35%). Sixty-one percent of the patients reported no side effects from continuous use. The most common side effect occurring beyond Day 21 of continuous use was breakthrough bleeding (reported in four patients). Survival analysis indicated that time on continuous triphasic use was positively related to parity >0 (p<.05) and the absence of side effects (p<.1).

The data suggest that successful continuous use is feasible with triphasic OCs, with few adverse side effects.