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Hormones, Periods,

Birth Control

Your Period (information gathered from and website)

As you wait for your first period, you may have lots of questions about what will happen. What will it feel like? What do I need to do to prepare? How do I use a tampon?

Getting your first period is an important milestone in a young woman’s life. It signals the beginning of a long phase of life (around 40 years!) that you may be fertile. This means that if you have sexual contact, you might get pregnant. While you may have learned about menstruation in school, you probably have questions about what to expect. This section is designed to provide you with all the information you need as you approach getting your period for the first time.

Most girls get their first period somewhere between the ages of 10 and 14, with an average of just over 12 years old. It’s hard to tell when your first period will arrive. It usually happens about two years after the first signs of puberty (usually breast development), and about a year after you begin growing pubic hair. You will also notice white or yellowish vaginal discharge in the few months leading up to your period.

There is no way to predict exactly when you will get your first period, and there is nothing you can do to make it start, except wait. If you are worried about your first period, talk to your family doctor.

If you are sexually active, you will need to consider the possibility that you could get pregnant once you have your period. In fact, you can even get pregnant if you’ve never menstruated, since it’s possible to ovulate before your first period. There are many forms of birth control available. 

What will my first period feel like?

You may find your first period comes and goes with very little in the way of symptoms, or you may find you experience quite a bit of discomfort. Common symptoms include:

  • Cramping in the lower abdomen

  • Breast tenderness

  • Lower backache

  • Diarrhea or nausea

  • Dizziness

Most of these symptoms do not last long, and can be treated with ibuprofen or other over-the-counter pain relief medications. A heating pad or hot water bottle on the abdomen or lower back can help ease pain in these areas. More details on menstrual pain and other symptoms can be found here .

How long will my first period last?

Your first period should last anywhere from 2 to 7 days. It may be very light, with just a few spots of brownish blood. Or it may start and end more brownish, but be brighter red on heavier flow days.

How do I know when I will get my next period?

It’s impossible to predict when your next period will start. Most girls and women go about 28 days from the first day of one period to the first day of the next, but anywhere from 21-35 days is normal. Especially in the first few years of menstruating, your period may be very irregular. If you track your period on a calendar (start day, number of days of bleeding, any symptoms), you will begin to notice a pattern over time. You can use this ‘menstrual diary‘ to keep track of your periods.

Menstrual Cycle Basics: 

What is menstruation?

Menstruation is the technical term for getting your period. About once a month, females who have gone through puberty will experience menstrual bleeding. This happens because the lining of the uterus has prepared itself for a possible pregnancy by becoming thicker and richer in blood vessels. If pregnancy does not occur, this thickened lining is shed, accompanied by bleeding. Bleeding usually lasts for 3-8 days. For most women, menstruation happens in a fairly regular, predictable pattern. The length of time from the first day of one period to the first day of the next period normally ranges from 21-35 days.

How does the menstrual cycle work?

The menstrual cycle is controlled by a complex orchestra of hormones, produced by two structures in the brain, the pituitary gland and the hypothalamus along with the ovaries.

If you just want a quick, general overview of the menstrual cycle, read this description.

For a more detailed review of the physical and hormonal changes that happen over the menstrual cycle, click here.

General overview of the menstrual cycle:

The menstrual cycle includes several phases. The exact timing of the phases of the cycle is a little bit different for every woman and can change over time.

Cycle days (approximate)Events of the menstrual cycle

Days 1-5

The first day of menstrual bleeding is considered Day 1 of the cycle.

Your period can last anywhere from 3 to 8 days, but 5 days is average.

Bleeding is usually heaviest on the first 2 days.

Days 6-14

Once the bleeding stops, the uterine lining (also called the endometrium) begins to prepare for the possibility of a pregnancy.

The uterine lining becomes thicker and enriched in blood and nutrients.

Day 14-25

Somewhere around day 14, an egg is released from one of the ovaries and begins its journey down the fallopian tubes to the uterus.

If sperm are present in the fallopian tube at this time, fertilization can occur.

In this case the fertilized egg will travel to the uterus and attempt to implant in the uterine wall.

Days 25-28

If the egg was not fertilized or implantation does not occur, hormonal changes signal the uterus to prepare to shed its lining, and the egg breaks down and is shed along with lining.

The cycle begins again on Day 1 menstrual bleeding.

What is normal bleeding?

There is a range of normal bleeding – some women have short, light periods and others have longer, heavy periods. Your period may also change over time.

Normal menstrual bleeding has the following features:

  • Your period lasts for 3-8 days

  • Your period comes again every 21-35 days (measured from the first day of one period to the first day of the next)

  • The total blood loss over the course of the period is around 2-3 tablespoons but secretions of other fluids can make it seem more

How will my birth control affect my bleeding?


Birth control methods such as the pill, patch, vaginal ring, shot and IUD can all impact your menstrual bleeding. Some birth control methods can increase bleeding, and some can decrease it. Many aspects of bleeding can be affected, and these effects can change over time. Periods can be longer, shorter, heavier, or lighter, depending on the method of birth control. Spotting and irregular bleeding are common side effects of most methods of hormonal birth control, especially in the first few months of use.


Birth control pills

Birth control pills were originally only packaged as 28 pills – 21 pills containing the hormone(s) required to suppress ovulation, and 7 placebo pills (no active ingredients). The 7 days of placebo were designed to allow menstruation to occur. Today there are a variety of regimens available, such as 24 days of active-ingredient pills and 4 days of placebo, and extended-cycle regimens that can be taken for up to a year to stop all menstrual bleeding.

No matter which birth control pill you are taking, you may experience irregular spotting or bleeding during the first few months of taking the birth control pill. This is more common when you are taking progestin-only pills (the ‘mini-pill’), compared to combination pills that contain estrogen and progestin. It is also more common to have spotting when taking a ‘monophasic’ pill (same dose of hormones every day), compared to a ‘triphasic’ pill (different dosages over the cycle). Spotting can also result from forgetting to take a pill, or taking it late. Taking your pill even a few hours later than normal can cause spotting, especially with the progestin-only pill.


Injected and implanted contraceptives

Irregular, unpredictable bleeding is very common in women using long-acting, progestin-based birth control methods (e.g., Depo Provera®, Implanon®). After a year of use, about half of women will have no periods.

Intrauterine devices


There are two types of IUDs available, the copper IUD and the progestin IUD. With the copper IUD, spotting between periods and heavier, longer, and more painful periods are common in the first three to six months. Most women find this improves over time, and normal or near-normal periods resume after a few months.

With a progestin IUD, spotting between periods and irregular periods are common in the first three to six months. Usually this improves over time and many women ultimately have light or absent periods with the progestin IUD. The progestin IUD can be effective for many years (a new one is reinserted after 5 years). A smaller mini-IUD is also available, and may be preferable for women who have not had a child.


Vaginal ring

This small, flexible ring is inserted high in the vagina, and releases estrogen and progestin, which prevent ovulation. The vaginal ring is usually left in for three weeks, and then removed for a week to allow menstruation to occur but it can be used continuously or in an extended fashion with a new ring every month. Spotting between periods may happen, particularly in the first three months.

Emergency contraceptives

The ‘morning after’ pill may affect the length of your menstrual cycle, causing your period to come earlier or later than you were expecting it to. If you take emergency contraceptive pills in the first three weeks of your cycle, your period is likely to come early. Your period may also last longer than normal. In most cases, the earlier you are in your cycle, the sooner your period will come. If you took emergency contraception in the later part of your cycle (after ovulation), your period may be delayed. Some women also experience spotting between periods after taking emergency contraception. Your next menstrual cycle may also be slightly longer than normal, but if your next period is more than a couple of days late, it is a good idea to use a pregnancy test.

Emergency contraception is not to be used as a regular method of birth control but, if needed, it can help prevent unplanned pregnancies.

Side effects of hormonal birth control

You may experience side effects when using any type of hormonal birth control. These vary a little depending on which type of birth control you are using. Tell your doctor about any side effects that are bothering you.

Although it is rare, hormonal birth control methods, especially those that contain estrogen, increase your risk of developing a blood clot in your leg (deep vein thrombosis). Seek medical help immediately if you have trouble breathing, which can happen if a clot moves into your lung (pulmonary embolism). A pulmonary embolism is a medical emergency.

For more info head to

Local Resources

Your family physician

Sexual Health Clinic

Online Resources

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