Signs And Symptoms Of First Menstrual Period (Menarche)

Here are some initial clues that your first menstrual period may be coming.

Signs And Symptoms

1. Your Age

The average age for the onset of menstruation is 11-13 years, but menarche can occur anywhere from 9-15 years of age. Physical activity and sedentary behavior can influence the onset of periods. Early or late menarche is associated with increased physical activity and a lower likelihood of sedentary behavior. The age of onset of the first menstrual period has decreased from about 15 years old, to 11-13, possibly due to improved nutrition.1


Another theory as to why periods may be starting earlier is the presence of estrogen-like chemicals in our environment, termed xenoestrogens. These are chemicals that we are all exposed to that can act like estrogen in our bodies. They are found in plastic, pesticides and environmental pollution. Late menarche (after the age of 15) can be due to hormone imbalances due to an underactive thyroid, pituitary problems or polycystic ovarian syndrome (PCOS).

2. Development Of Secondary Sex Characteristics

One to two years prior to the start of your period, the changes associated with puberty may begin, such as breast development, growth of underarm and pubic hair, changes in fat distribution to your buttocks, thighs and hips and widening of your hips.


About two weeks before your first period, you may notice a twinge on one side or the other of your lower abdomen and some clear, stretchy mucous-like vaginal discharge, also called egg white or cervical mucous. These can be signs of ovulation and a period would be expected to arrive about 2 weeks later. Ovulation may not occur with periods when they are first starting; it may take even a few years for regular ovulation to occur.

Within the week prior to your first period, you may notice premenstrual syndrome (PMS) symptoms like worsening acne, breast tenderness, and mood changes such as feeling more sad, emotional, weepy, anxious or irritable. You may feel cramps in your lower abdomen or pain in your lower back.


You may have some vaginal discharge that may be clear, white, yellowish, brown or red. The discharge may be watery, stretchy or thick. You may also notice a bit of blood on the toilet tissue when you wipe.2

If you see any vaginal discharge, it is best to bring this to the attention of an adult that you trust to ensure that it is normal and not a sign of an infection. Your first period may only involve some light spotting, or it may be a normal or even a heavy period, everyone is different. If you begin to see signs that your period may be approaching, you will want to be prepared with tampons, pad or a menstrual cup. Accidents are common at first as you are adjusting to your new status as an adult female.


What To Expect With Your Period

Every woman is different! In some women, periods are nothing more than some vaginal bleeding each month, with little or no other symptoms, where for some women there can be more intense PMS symptoms and severe menstrual cramps.

Some women have regular periods right from the start, while others may take a few years to become regular. Once they are coming regularly, periods should arrive every 26-32 days. Irregular periods can be a sign of an endocrine problem such as hypothyroidism, HPA axis dysfunction, pregnancy or polycystic ovarian syndrome (PCOS) and should be investigated through blood testing and pelvic and transvaginal ultrasound.


What Is A Normal Period Like?

Normally a period will last 4-7 days, with heavier flow at the beginning for a day or two and then tapering off for 2-3 days. There may be cramping, but it shouldn’t be debilitating. Within 1-3 years of menarche, periods should come regularly every 26-32 days, with minimal or no PMS symptoms.3

When Should You See A Doctor?

You should see a doctor if:

  • You have been having periods for 3 or more years and they are still not coming regularly
  • Period cramps are so painful that you can’t function, over the counter medications don’t help or you vomit or pass out from the pain
  • You have migraines associated with your period
  • Periods are so heavy that you can’t maintain a normal blood iron level
  • You pass large clots with your period
  • Your periods usually come regularly and it is late or missed altogether
  • You are 15 years old or over and your period hasn’t started yet
  • You are 8 years old or younger and your period has started
  • Your periods are irregular and you have signs or symptoms of excess male hormones (cystic acne, hair loss, excessive facial or body hair)