The pill and menstruation: what are the effects on the menstrual cycle?

Many women take the pill as a means of contraception. Indeed, it is an easy-to-use contraceptive method, which can be used by a good number of women. At Elia, we wonder what impact this contraception has on the menstrual cycle.

What is the contraceptive pill?

The pill is a means of contraception, composed of synthetic hormones called estrogen and progestin. It is an effective method of contraception (99% effectiveness) if taken correctly. Beyond the hormones that may not be suitable for some women, this contraceptive method has the disadvantage of having to be taken every day.

As such, there are two types:

  • estrogen-progestin pills, which contain both hormones
  • and progestin-only pills, which contain only a progestin.

These two types of contraceptives do not work in the same way. While the progestin-only version affects only the uterine lining and mucus (the blockage of ovulation depends on the progestin), the estrogen-progestin version affects several aspects: it blocks ovulation and thickens the mucus, which prevents sperm from crossing the cervix and an egg from implanting. However, the impact of this contraception on menstruation is the same for each type of pill.

How do birth control pills affect menstruation?

Most pills come in packs of 28 or 21 tablets. In the 28-pill packs, 7 pills are actually placebos. Hormones are therefore taken for 21 consecutive days, and then, for a week, no hormones are ingested and that is when menstruation occurs. Also, menstruation on the contraceptive pill is less painful and often shorter.

It can happen, even with the pill, to have periods late or early: indeed the body is not a clock. However, as this contraceptive method is not 100% effective, it is better to check that there is no pregnancy.

Stopping your period altogether

Since bleeding on the pill is a withdrawal hemorrhage, you can choose to take your pack continuously, i.e., skip the 7-day break (or the placebos) and start a new one. This will allow you to miss your period. However, this state is not definitive, we generally observe the resumption of menstruation as soon as the pill is stopped.

It is possible to experience light blood loss(spotting) if you skip the 7-day break for several cycles in a row. In this case, stick to the next 7 days of scheduled discontinuation to see the spotting disappear. Some people will have periods or rather bleeding that is so light and short that they will feel as if they have no real flow. It is estimated that 1 woman in 10 does not have a withdrawal hemorrhage. On the other hand, they may have spotting.

Withdrawal bleeding

Menstruation on the pill is called"withdrawal bleeding" because the discharge is not a real period. This contraceptive device causes false bleeding during the week of discontinuation. The word "deprivation" refers to the absence of hormones during these 7 days of stopping or during the taking of placebos. It is the rather rapid fall in the level of hormones during these 7 days that will cause bleeding under the pill called withdrawal bleeding. This corresponds to the evacuation of the uterine mucous membrane that covers the cavity of the uterus: the endometrium.

Light blood flow

Beyond the period on the pill, it is common to have bleeding outside the hormonal stop, this is called spotting.

If it is normal to have blood loss outside of menstruation during the first 3 months of use of this method of contraception, it is not normal for this to continue afterwards. Consult your doctor, gynaecologist or midwife after this initial adaptation phase if the symptoms persist: it will probably be necessary to change the pill and opt for a different hormone level.

If you forget to take your daily pill, the drop in hormone levels may cause bleeding or even delay your menstrual periods.

How do I know if my bleeding on the pill is normal?

When you take the pill, it is normal to see a change in your flow compared to when you were not taking it.

During the first few months of use, you may experience light bleeding outside of your period, called spotting. But if it lasts longer than three months, talk to your health care provider.

Menstrual flow on the pill can also vary over time. Finally, if you have no or almost no bleeding during the discontinuation phase, even though you have taken your pack properly (no missed periods, delays, vomiting or diarrhea), it is considered normal.

What to do in case of painful bleeding on the pill?

Having pain during your period is never normal. If you have pain during your period on the pill, consult your doctor. The first thing to do is to check that there is no risk of illness or pregnancy. Changing the generation of the pill and the hormone level may also be a good solution.

What alternatives to the pill do not stop menstruation?

Everyone is different and the body reacts differently to different contraceptives. Thus, some contraceptive generations or active components, depending on the dosage, will cause a decrease in the volume of bleeding, sometimes even stopping it, while others will cause a blood flow similar to that of natural menstruation.

There are natural contraceptive methods that do not stop menstruation, such as the copper IUD, which will cause heavier blood loss. The implant and the hormonal IUD can also stop the menstrual flow.

What about the morning-after pill?

If you have had risky sex and do not want to get pregnant, the morning-after pill, also known as emergency contraception, must be taken within 3 to 5 days of your period. It is free and does not require a prescription for minors. Taking it starts the menstrual cycle, so it is normal for your period to arrive more quickly after taking this pill!

FAQ about the pill and menstruation

When does the period arrive when you take the pill?

Menstruation appears 2 to 3 days after the last hormonal pill is stopped, i.e. after the 21 days of taking the pill, during the 7-day stop period or the 7-day placebo period.

Does the pill reduce menstruation?

Yes, menstruation on the pill, otherwise known as withdrawal bleeding, will tend to reduce blood flow and the duration of menstruation.

Can the pill prolong a period?

Although menstrual periods, their intensity and duration may vary over time, they will usually be shorter and less heavy on the pill. Some women may experience bleeding that occurs outside of their menstrual period. This is called spotting.

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