When should a patient taking Tri-Cyclen Lo (norgestimate and ethinyl estradiol), a combination oral contraceptive, expect to have her menstrual period?

When to Expect Menses on Tri-Cyclen Lo

Withdrawal bleeding (menstrual period) should occur during the 7-day hormone-free interval (placebo pill week) of each 28-day cycle, typically starting 2-3 days after beginning the inactive pills. 1

Standard Tri-Cyclen Lo Cycle Structure

Tri-Cyclen Lo follows a traditional cyclic combined oral contraceptive regimen with:

• 21 days of active hormonal pills (containing norgestimate and ethinyl estradiol in a triphasic pattern: 180/215/250 mcg norgestimate with 25 mcg ethinyl estradiol) 2
• 7 days of inactive placebo pills during which withdrawal bleeding occurs 1

Expected Bleeding Pattern

Most women will experience withdrawal bleeding during the hormone-free week, though the exact timing and characteristics vary:

• Bleeding typically begins 2-3 days after starting the placebo pills 1
• The bleeding pattern may be lighter and shorter than natural menstruation due to the lower estrogen dose (25 mcg) in Tri-Cyclen Lo 2
• Unscheduled spotting or breakthrough bleeding is common during the first 3-6 months of use (14-17% of cycles in clinical trials), but this generally improves with continued use 1, 2

Important Clinical Considerations

Amenorrhea (Absence of Bleeding)

If withdrawal bleeding does not occur during the placebo week, pregnancy must be ruled out before continuing the next pack:

• If one period is missed and pills were taken correctly, pregnancy is unlikely but should be considered 3
• If two consecutive periods are missed, pregnancy must be ruled out regardless of adherence 3
• Some women may experience amenorrhea while using combined oral contraceptives, which is not necessarily harmful but requires pregnancy exclusion 3

Breakthrough Bleeding Management

Unscheduled bleeding during active pill weeks is generally not harmful and does not indicate contraceptive failure:

• Emphasize consistent daily pill-taking at the same time to minimize breakthrough bleeding 1
• Bleeding irregularities typically resolve after 3-6 months of continuous use 1
• If bleeding persists beyond 3-6 months or occurs after previously regular cycles, evaluate for pregnancy, missed pills, or underlying pathology 3

Extended/Continuous Regimens

While Tri-Cyclen Lo is packaged for traditional 28-day cycling, extended or continuous regimens (skipping placebo weeks) can be used to reduce or eliminate menstrual periods entirely:

• This approach involves taking only active pills continuously for 84+ days or indefinitely 4, 5, 6
• Extended regimens are particularly useful for managing menstrual-related symptoms like dysmenorrhea 7, 4
• A planned 3-4 day hormone-free interval can be used to manage breakthrough bleeding if it occurs during extended use 1

Common Pitfalls to Avoid

• Do not use withdrawal bleeding as a pregnancy test - absence of bleeding does not reliably exclude pregnancy, and presence of bleeding does not confirm non-pregnancy 3
• Do not discontinue the pill due to early breakthrough bleeding - this is expected during the first 3-6 months and typically resolves with continued use 1
• Do not assume amenorrhea indicates a problem - some women naturally experience very light or absent withdrawal bleeding on low-dose formulations like Tri-Cyclen Lo 3