Birth control and your period: the Pill

Do you have a “real” period on the pill?

When you’re on the pill*, bleeding typically happens at the end of each pack. These are the days you take no pills or take the pills in your pack with no (or few) hormones — also known as placebo pills. This bleeding will probably be different than your period would be if you weren’t taking the pill — and you may have times when you bleed very little or not at all.

Top things to know:

• Your “period” on the pill is actually called withdrawal bleeding, and happens when the levels of hormones in your pills drop
• Withdrawal bleeding may be lighter or slightly different than the period you had before taking the pill
• Some people experience only spotting or don’t bleed at all during placebo pill days
• Your bleeding on the pill is likely to change over time

Do I get a “real” period on the pill?

Nope. The bleeding you get when you’re on the pill is not the same as a menstrual period.

When you’re taking the pill, your period is technically called withdrawal bleeding, referring to the withdrawal of hormones in your pill. The drop in hormones levels causes the lining of your uterus (the endometrium) to shed (1). This bleeding may be slightly different than the period you had before taking the pill. It also may change over time while taking the pill.

What exactly is happening my body? Am I ovulating on the pill?*

No. If you take your pill consistently and correctly, you shouldn’t ovulate. This is the primary way the pill prevents pregnancy. In a usual (no-pill) cycle, the body’s natural reproductive hormones fluctuate up and down, taking your body through a process of preparing an egg for release, releasing that egg, and preparing your uterus to accept a potentially fertilized egg.

The hormones in the pill stop and prevent your ovaries from preparing and releasing eggs. They stop the usual hormonal “cycling”, including ovulation, the typical growth of the endometrium, and the natural period.

Why is my bleeding different on the pill?

The pill prevents your endometrium from growing thicker, as it would in a typical menstrual cycle (2, 3). It also prevents ovulation, and the typical cycling of reproductive hormones. When you have withdrawal bleeding, the bleeding tends to be lighter than normal menstrual bleeding.

It’s also possible to have no withdrawal bleeding or only spotting during the days you take inactive pills (or no pills). This is more common for people taking higher doses of estrogen, or a pill with a shorter (or no) hormone-free interval (most pill packs have seven placebo pills but check your pack’s box and infosheet if you’re not sure.) (4, 5).

What’s “normal” bleeding while on the pill?

Your body’s response to your pill will depend on the type of pill you take, and your own body’s hormones. On a typical 21/7 monophasic pill (where all active pills have the same amount of hormones — check your pack), bleeding may start on day 2 or 3 of your placebo week and last 3–5 days on average. A few people may have only one day of bleeding mid-week, and others may have bleeding that extends into their next pill pack. Up to 1 in 10 have no withdrawal bleeding at all (not including spotting) (5).

Bleeding on the pill is also likely to change over time. In people using the 24/4 day pill (24 active hormone pills & 4 placebo pills), about 1–2 in 10 had no significant withdrawal bleeding by the 6th pill pack (4). Bleeding also tended to decrease over time.

No bleeding can also signal a pregnancy. Take a pregnancy test if you’re unsure, especially if you haven’t taken your pills correctly in the previous pack.

Unexpected spotting and bleeding on the pill

Bleeding and spotting can happen outside of your usual period time. This is called breakthrough bleeding. It doesn’t mean your pill isn’t working, but it can be frustrating to deal with (2). Up to 1 in 5 people experience breakthrough bleeding when first taking the pill (6). It is not usually a cause for concern and will often stop after a few weeks or months (7). Others will need to try a different pill brand, with different levels of hormones. Many experts recommend choosing a pill with the lowest dose of estrogen (ethinylestradiol/EE), and only changing to a higher dose if breakthrough bleeding is a persistent problem (7).

Spotting can also be caused by missing pills, as the drop in hormone levels can cause a small amount of withdrawal bleeding.

What’s normal

• Unexpected spotting for the first few months while taking a new pill (talk to your healthcare provider if it’s still happening after 3 months)
• Withdrawal bleeding that is lighter, or shorter than your period before the pill
• Withdrawal bleeding that changes slightly over time while on the pill
• Having little or no bleeding during your placebo week after taking your pills correctly

*This article refers to the use of combined hormonal contraceptive pills, which contain both estrogen and progestin (the most common type). Bleeding patterns will be different for people taking the progestin-only minipill.

References

1. Sulak PJ, Cressman BE, Waldrop E, Holleman S, Kuehl TJ. Extending the duration of active oral contraceptive pills to manage hormone withdrawal symptoms. Obstetrics & Gynecology. 1997 Feb 1;89(2):179–83.
2. Johnson JV, Grubb GS, Constantine GD. Endometrial histology following 1 year of a continuous daily regimen of levonorgestrel 90 μg/ethinyl estradiol 20 μg. Contraception. 2007 Jan 31;75(1):23–6.
3. Wright KP, Johnson JV. Evaluation of extended and continuous use oral contraceptives. 2008 Therapeutics and Clinical Risk Management, 4(5), 905–911.
4. Apter D, Zimmerman Y, Beekman L, Mawet M, Maillard C, Foidart JM, Bennink HJ. Bleeding pattern and cycle control with estetrol-containing combined oral contraceptives: results from a phase II, randomised, dose-finding study (FIESTA). Contraception. 2016 Oct 31;94(4):366–73.
5. Kwiecien M, Edelman A, Nichols MD, Jensen JT. Bleeding patterns and patient acceptability of standard or continuous dosing regimens of a low-dose oral contraceptive: a randomized trial. Contraception. 2003 Jan 31;67(1):9–13.
6. Ahrendt HJ, Makalová D, Parke S, Mellinger U, Mansour D. Bleeding pattern and cycle control with an estradiol-based oral contraceptive: a seven-cycle, randomized comparative trial of estradiol valerate/dienogest and ethinyl estradiol/levonorgestrel. Contraception. 2009 Nov 30;80(5):436–44.
7. Schrager S, Abnormal uterine bleeding associated with hormonal contraception. Am Fam Physician. 2002 May 15;65(10):2073–81.