Menstrual Periods

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You are born with two small, grape-shaped ovaries inside of your belly on either side of your uterus. Ovaries are filled with hundreds of thousands of eggs. When you reach puberty and you are becoming a woman, your ovaries make hormones (especially estrogen) that cause breast development and menstrual periods. The pituitary gland in your brain releases chemical messengers (FSH and LH) called gonadotropins, that “tell” your ovaries to make hormones such as estrogen and to release a mature egg once a month. The egg then travels towards the uterus. If the egg is not fertilized by a sperm, then two weeks later, the blood filled lining of the uterus (called the endometrium) that becomes thicker between periods passes out of your body through your vagina. This flow, which comes out as blood, is your menstrual period. The whole process is called menstruation, and it will begin when your body is ready.

What will my period feel like?

Your period feels like liquid flowing slowly, with starts and stops, out of your vagina. This is exactly what happens during your period. Although it may seem like a lot of blood, only a small amount is released at a time. It’s normal to see small clots of blood from your vagina on the toilet paper after you urinate (pee).

What if I haven’t had my period yet?

It’s normal to get your period as early as 9 years old or as late as 15 years old. This is a big time range and it’s hard to be one of the first or one of the last. Girls who are active in sports or are very thin may not get their period until a later age. Losing weight while you are in your growth spurt can also delay your periods. Talk to your parent or your healthcare provider about your worries and concerns. If you haven’t gotten your period by the time you are 15 or if you started your breast development more than three years ago and haven’t gotten your period, get a check-up with your health care provider (HCP) just to make sure everything is okay. Your HCP sees many girls who develop late, so don’t be embarrassed to ask. Your HCP may do a genital exam and check to see if your hymen (a thin piece of tissue that partially blocks the entrance to your vagina) is open. Some girls are born with an “imperforate hymen,” which means that the hymen doesn’t have an opening, and blood cannot leave the vagina. Rarely, girls are born with a condition called Mayer Rokitansky Kuster Hauser syndrome (MRKH), which is an incomplete vagina and/or small or absent uterus, so they don’t get their period for this reason. It’s a good idea to get regular check-ups during puberty just to make sure that everything is okay.

How often will I get my period?

You will likely get your period about once every month. A typical menstrual cycle is about 28 days. This means that there will be about 28 days from the first day of your period to the first day of your next period. 28 days is an average number, but anywhere between 21 and 35 days is normal. In the first year, most girls have at least 4 periods; the second year, at least 6 periods; and for the 3-5th year, at least 8 periods. Most adult women have  9 to 12 periods a year. Your period will usually last between 3 and 7 days. The amount of blood flow you have will probably be different each day. You will usually have the most blood in the beginning of your period and the least towards the end. When you are first getting your period, you may have a very heavy period one cycle and very light one the next.

What if my periods don’t come regularly?

You may be in the first or second year of having periods or you may be one of those adolescents whose periods may be affected by changes in body weight or diet, increased stress, eating disorders, exercise, illness, or going away to camp or college. Remember that if you are having sexual intercourse, an irregular period could be a sign of pregnancy. Your period may last 1 day or it may last 6 or 7. All of your cycles may not be the same number of days, and the length of your cycle may change over time. It is common for a girl just starting her period to have irregular periods for a year or two.

Periods too far apart. You may only get your period 3-4 times a year, instead of once a month. If you are having your periods only a few times a year, this may be because of stress, intense exercise, weight loss, or diet. Too few periods could also be caused by a mild hormone imbalance called Polycystic Ovary Syndrome (PCOS). Girls with PCOS often have acne, excess hair growth, or weight problems in addition to irregular periods. You should check with your HCP if your period lasts longer than 7 days and if there are more than 35 days between your periods (from the first day of your period to the first day of your next period).

Periods too close together. You may get your period every two or three weeks. This can be because of stress, some types of exercise, or other changes in your life. If your periods are less than 21 days apart, or if your period seems to be too heavy, your provider may want to check your blood count to see if you are anemic. If you are anemic, you may have too few red blood cells, or too little hemoglobin (oxygen-carrying protein in your red blood cells). People who are anemic (because of heavy periods) need to eat foods that have iron and take an iron supplement. Your HCP will tell you the dose (how much) to take and when you will need to have a follow-up blood test.

Why should I track of my period?

Keeping track of when your period starts and stops is a good way to see if there is a pattern to your menstrual cycle. It is also important to write down how many days you have your period and the amount of flow you have. Bring your Period Trackers with you when you see your health care provider so that he or she can evaluate your cycle.

My Monthly Period & Symptom Tracker

My Monthly Period & Symptom Tracker is an easy way to keep track of your menstrual flow, and it’s also a way to keep track of cramps, and/or PMS and period symptoms (if you have them) each month.

  • Review the sample Monthly Period & Symptom Tracker.
  • Print copies of My Monthly Period & Symptom Tracker.
  • Simply make a check mark in the appropriate box (or boxes) for each day of the month. If you don’t have any flow or any symptoms on any given day, leave the box empty. Refer to the Blood Flow Key at the bottom for “Flow” definitions.
  • The dates at the top are the same as the dates in one month. Some months have 28 days, others have 30 or 31.
  • Remember to bring My Monthly Period & Symptom Tracker with you to your medical appointments.

Sample Monthly Period & Symptom Tracker

My Monthly Period & Symptom Tracker

My Yearly Period Tracker

My Yearly Period Tracker is a simple and convenient way to track your period throughout the year.

  • Review the sample Yearly Period Tracker.
  • Print a copy of My Yearly Period Tracker.
  • Refer to the Key at the bottom to learn how to fill in the box with the appropriate letter(s). Place a “T” in the box for the hormone pill taken and place an “R” for reminder (placebo) pills.
  • Be sure to indicate if you’ve taken a pill during your period by putting a B/T or B/R in the box.
  • Remember to bring My Yearly Period Tracker with you to your medical appointments.
  • Talk to your health care provider about whether you should use the monthly and/or yearly tracker to track your period.

Sample Yearly Period Tracker

My Yearly Period Tracker

What if I skip a period?

If you miss your period, it could be because of a change in your body or in your life. If you are under stress, you’ve been sick, you are exercising a lot, or you’ve lost weight, you may skip a period. It is common to skip a period once in a while, especially during the first year that you are getting it. However, if you are having unprotected sexual intercourse or close sexual contact, or if your birth control method has failed, it could also mean that you are pregnant. If you think you may be pregnant, it is very important to see your health care provider. If you skip many periods, you should talk to your healthcare provider and see why this is happening.

What if I have big clots of blood during my period?

Small, dark, chunky clots of blood can be normal. Some women get them during their period when they have days of heavy cramping and heavy bleeding. Your body usually makes things called “anti-coagulants,” that keep your blood from clotting as it moves to your vagina and out of your body. But during days of heavy bleeding and cramping, the blood may be leaving the uterus so quickly there isn’t time to release these anti-coagulants. The blood then clots. If you have clots that are bigger than the size of a quarter, talk with your health care provider.

What if I get spots of blood on my underwear between my periods?

Bleeding in the middle of your cycle could mean different things. Some women bleed a little bit during the middle of their cycle, when they ovulate (when a mature egg is released from your ovaries). This is nothing to worry about. Other times, “spotting” occurs because of an infection such as a sexually transmitted infection (if you are having sexual intercourse). Very rarely, “spotting” can be because of a polyp (a lump that may need to be removed surgically), but this is not very common. You should talk to your health care provider if you have bleeding when you don’t have your period.

Remember to keep track of your menstrual periods and check in with your health care provider if your bleeding pattern changes.