What To Do If Your Child’s Period Hasn't Started By 16

Has your child reached Sweet Sixteen without getting a menstrual cycle? Read on to learn more about what you should do.

 If your child or daughter is 16 and hasn’t gotten their first period yet: you might be asking yourself, when? A period is a sign of reproductive maturing and most people tend to get their first period between the ages of 9 and 15. (The average age for a person to have their first menstrual period is 12.5.) A period will typically appear two years after the onset of puberty, early signs of which include developing breast buds and hair growth, including pubic hair. 

If your daughter or assigned female at birth child has begun puberty but not yet had their first menstrual cycle by the age of 16 you might be feeling understandably concerned. According to WebMD, by age 15, 98% of teens have started their periods.

But there are a number of factors that affect menstrual cycles from family history to physical problems to too much exercise. If your daughter or child hasn’t had their period by age 16, it’s a good idea to book an appointment with a doctor to figure out the cause.

Related reading: Signs and symptoms your child’s period may be on the way 

Group of teens wearing Kt by Knix period underwear

Don't panic.

You're not alone. It's not uncommon for some girls and non binary people to start their period later than other, and it doesn't necessarily mean they have any health problems. There’s a good chance your daughter or child might just be a late bloomer. If you are worried, talk to your doctor. In the meantime, try not to stress too much about it.

Make an appointment with your primary care doctor.

Your doctor will ask your daughter or child a series of questions, including:

  1. What are your symptoms?
  2. How long have you been experiencing them?
  3. Are there any other symptoms that you have been experiencing?
  4. Are there any medications that you are taking regularly or have recently started taking (including vitamins and supplements)?
  5. Have you ever been diagnosed with any medical conditions before (including heart disease, diabetes, etc.)?

PS: Be prepared for when their period does come. Shop period underwear now to prevent leaks, and reduce stress and worry for you and your teen.

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They might order some blood tests.

Not having a period by the age of 15 is called primary amenorrhea. This is different than secondary amenorrhea, which happens when a person who has had their period doesn’t get one for three months or longer. 

Blood tests are a common part of diagnosing the cause of amenorrhea. They can help rule out serious health problems like pregnancy and thyroid disease and are also used to help diagnose other conditions that can cause primary amenorrhea, such as polycystic ovary syndrome (PCOS).

Typical Reasons for Delayed Periods


Do you have a family history of late menstrual periods?If the women in your family usually do not get their periods until later on, it could be the case that your daughter or child is just a late-bloomer. This is not a cause for concern and you simply have to be patient. Their menstrual period will come eventually!

Low weight

Low weight (usually caused by an eating disorder) is a common cause of primary amenorrhea because it affects the way hormones are produced in the body. If your daughter is 16 and underweight and still hasn’t had a period, bring her to a doctor.

Read on: Are irregular periods normal?

Two teens wearing Kt by Knix period underwear


If your child has one or more stressful situations in their life, that might be causing a delayed period. If they are under a lot of academic pressure to perform, are involved in competitive extracurricular activities or have stressful things going on at home (e.g. divorce) it may be affecting the timing of their first period.


There are a number of drugs that may cause delayed periods, including ones that treat cancer, high blood pressure, allergies and depression. Confirm with a doctor whether your child’s medications might be interfering with their period or not.

Thyroid disorder

Sometimes the thyroid gland, which regulates how the body uses fats and carbohydrates, could be the culprit. An underactive or overactive thyroid gland causing hormone imbalance may cause a delayed period.

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They might need to see a gynecologist or endocrinologist about their menstrual cycle.

If by your child’s 16th birthday they still haven't started their period, it's time to make an appointment with a doctor. The sooner you get in there, the better. Make sure to tell them about any health issues or concerns that could be affecting your child’s period. They might need to see a gynecologist or an endocrinologist (an expert on hormones). 

These doctors will be able to check for any physical reasons why they might not be having a period yet, like early ovarian failure or other hormonal problems that can cause changes in your menstrual cycle. They might order a pelvic ultrasound or a pelvic exam to determine the cause.

Whether they suspect any medical causes for your delay in menstruation or not, there are some other steps that can be taken from here:

  1. You might want to talk with a nutritionist or dietician about starting an exercise routine that doesn't include high impact activities (running), which puts pressure on the pelvic area and could cause the uterus not to develop correctly;
  2. A psychiatrist or psychologist can help provide therapy for any underlying mental health issues such as depression

Read on: Is it possible to make your period come faster?

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Next steps

If your child hasn’t started their period by 16, it's something to bring up with their doctor. It's not a big deal, and there are a few possible causes that can be easily treated. However, if you have any concerns or questions, don't hesitate to reach out to a doctor or another health care professional. Make sure your child understands the basics like how to insert a tampon.

And don't forget that once their period comes, missed periods or irregular periods are very normal for the first few years. Read more about what's normal and not for menstrual periods in our free downloadable period guide

Be prepared: Shop period underwear now to prevent leaks once their period starts.

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