Will continuous use of birth control (contraceptives) for 1 year cause breakthrough bleeding or irregular menstrual cycles?

From the Guidelines

Taking birth control continuously for a year may result in breakthrough bleeding for some women, though many will experience fewer or no periods over time, with approximately 50% of women experiencing unpredictable spotting or bleeding during the first 3-6 months, which typically decreases with continued use 1. When using continuous hormonal contraception, such as skipping the placebo week in combined oral contraceptives, women may experience breakthrough bleeding due to the endometrial lining becoming unstable under continuous hormones.

Key Points to Consider

• Breakthrough bleeding is generally not harmful and often resolves with time 1.
• Continuous birth control is considered safe and effective, with the added benefit of reducing menstrual symptoms and conditions like endometriosis or menstrual migraines.
• If breakthrough bleeding becomes problematic, a healthcare provider might recommend a 3-4 day hormone-free break to allow for a controlled withdrawal bleed before resuming continuous use 1.
• Treatment options for bleeding irregularities may include NSAIDs, hormonal treatment, or antifibrinolytic agents, depending on the patient's preferences, treatment goals, and medical history 1.

Management of Bleeding Irregularities

• Explore patient goals, including continued method use or method discontinuation 1.
• Provide reassurance and advise the patient that they may contact their provider at any time to discuss bleeding irregularities or other side effects 1.
• Consider an underlying health condition, such as interactions with other medications, sexually transmitted infections, pregnancy, thyroid disorders, or new pathologic uterine conditions, and treat the condition or refer for care if necessary 1.

From the FDA Drug Label

Breakthrough bleeding, spotting, and amenorrhea are frequent reasons for patients discontinuing oral contraceptives. Breakthrough bleeding and spotting are sometimes encountered in patients on oral contraceptives, especially during the first three months of use In the event of amenorrhea, pregnancy should be ruled out

Breakthrough bleeding and spotting are possible when taking birth control continuously for 1 year, as these are frequent reasons for patients discontinuing oral contraceptives.

• Amenorrhea (absence of menstruation) may also occur, and pregnancy should be ruled out in such cases. It is not explicitly stated in the label how long the patient has been taking the medication, but breakthrough bleeding and spotting are more common during the first three months of use 2 2.

From the Research

Breakthrough Bleeding and Continuous Birth Control Use

• Breakthrough bleeding is a common side effect of hormonal contraception, and its frequency can vary depending on the type and dose of the contraceptive used 3, 4, 5.
• Studies have shown that breakthrough bleeding typically decreases over time with continuous use of combined oral contraceptives (COCs) 4, 5.
• A study comparing bleeding patterns in women using a combined contraceptive vaginal ring or a low-dose combined oral contraceptive on a menstrually signaled regimen found that bleeding/spotting days decreased from the first 90-day reference period to the fourth 4.
• Another study using model-based meta-analysis found that breakthrough bleeding is significantly increased upon initiation of COC use but subsides over time, with the time needed to return to baseline depending on the ethinyl estradiol (EE) dose and progestin used 5.
• Extended-cycle oral contraceptives, which offer fewer or no withdrawal bleeds over the course of one year, may be associated with initial increased breakthrough bleeding, but this can be managed with careful counseling and patient education 6.

Factors Influencing Breakthrough Bleeding

• The dose and type of progestin and estrogen in the contraceptive can affect the frequency and duration of breakthrough bleeding 3, 5.
• The ratio of progestin to estrogen in the contraceptive can also impact bleeding patterns 3.
• Individual factors, such as medical history and demographics, may also influence the risk and frequency of breakthrough bleeding 5.

Managing Breakthrough Bleeding

• Patient education on expected bleeding patterns is essential to compliance and continuation of contraceptive use 3, 4.
• Approaches to the evaluation and treatment of intermenstrual bleeding with contraceptive methods are available, including the use of a 4-day "treatment withdrawal" to stop bleeding 4.
• Counseling on the risks and side effects of extended-cycle oral contraceptives is comparable to that of traditional oral contraceptives 6.