Blood pressure is a measure of the force of your blood, pushing against the arteries in your body as it moves along. High blood pressure (hypertension) happens when the blood is being pushed too hard around the body, while low blood pressure (hypotension) happens when there isn't enough blood being pushed around your body.

Blood pressure readings have two numbers. For instance, your child's reading could be 115/62. The first number is the systolic pressure, which indicates how hard blood moves around your body when the heart is pumping. The second number is the diastolic pressure, which indicates how hard blood moves around our body between heartbeats, when the heart is resting and filling itself with blood. Then do you know the normal blood pressure for children? Keep reading on to learn that. 

Measuring Blood Pressure

Blood pressure is measured with a stethoscope and sphygmomanometer, which has a small pump that can be inflated with air and rubber cuff that can be secured around the upper arm. When you inflate it with air, the pressure will stop your blood flow for a few seconds. When you release the air from the rubber cuff, your blood resumes its flow. By using a stethoscope, your doctor can find out what your systolic and diastolic pressures are.

Factors That Can Affect a Child's Normal Blood Pressure

What is considered to be normal blood pressure in children depends on several factors, like height, age and sex. The biggest factor in children is their height; taller kids will have higher normal blood pressure than shorter kids. Also note that it's normal for children's blood pressure to change as they get older, and grow taller.

Normal Blood Pressure for Children

As indicated above, normal blood pressure will vary depending on how old and how tall a child is. Below are the three main categories children will fall into:

3-5 Yrs Old

You're probably thinking that three is too young, but according to the American Heart Association, parents should start checking their child's blood pressure regularly when they turn three.

The average upper limit for systolic blood pressure in children in this category will range from 104-116 depending again on height and sex. The average upper limit for diastolic blood pressure in children in this category will range from 63-74.

Average systolic pressures for boys and girls aged between 3 and 5 can be better seen in the chart below:

6-9 Yrs Old

Want to know the normal blood pressure for children at this group? The average upper limit for systolic blood pressure will range from 108-121. The average upper limit for diastolic blood pressure in children in this category will range from 71-81.

Average systolic pressures for boys and girls aged between 6 and 9 can be better seen in the chart below:

10-12 Yrs Old

The average upper limit for systolic blood pressure in children in this category will range from 114-127. The average upper limit for diastolic blood pressure in children in this category will range from 77-83.

Average systolic pressures for boys and girls aged between 10 and 12 can be better seen in the chart below:

High Blood Pressure in Children

If the results are not in the range of normal blood pressure for children listed above, your children may have high or low blood pressure, which will be talked below. 

Unlike in adults, high blood pressure is harder to detect in children. Adults who have a blood pressure over 140/90 are usually considered to have high blood pressure. It doesn't work that way with children though. In general, children who have a blood pressure higher than 95% of children of the same gender, age and height can be diagnosed with high blood pressure. Since children's blood pressures will vary greatly based on many factors as they're growing up, there is no set range we can use as we do with adults.

High blood pressure doesn't have any glaring symptoms until it's too late. When it does become a severe problem, symptoms your child may complain about include blurry vision, headaches, shortness of breath, and mild chest pains. Younger children who suffer from high blood pressure will usually be suffering from a bigger, underlying problem such as heart defects or kidney diseases. High blood pressure in older children is usually the result of obesity, type 2 diabetes or an inactive lifestyle.

If a child suffers from high blood pressure, lifestyle changes have to made, including a change of diet and an increase of physical activity. By ensuring your child maintains a healthy diet full of vegetables, fruits and whole grains, and steering him or her away from high-calorie/low-nutrition foods, you're already on the right path towards lowing your child's high blood pressure. Something else you should pay attention to if your child has high blood pressure is his or her sodium intake. Make sure this is no more than 1200mg for children aged 4-8 and no more than 1500 for children over the age of 8. Increasing physical activity is also extremely important; anything from bike rides to daily hikes can get the heart pumping properly and lower blood pressure.

Low Blood Pressure in Children

Low blood pressure may be a goal for many adults, but children with a lower than normal blood pressure can be facing serious danger. Hypotension (low blood pressure) can happen in children for many reasons, some of which can be easily cured (dehydration), while others can be more complex and life-threatening (disease).

• Dehydration. Possible the most common reason for low blood pressure in children, dehydration occurs when there's not enough water in a person's body. Although it sounds simple enough to reverse (by drinking more water), dehydration shouldn't be taken lightly as its side-effects can include severe diarrhea, excessive sweating or fever. Low blood pressure is another symptom; when a child's body doesn't have enough fluids, there will be a decrease in blood volume, and low blood pressure as a result.
• Medications. Some medications can severely impact your blood vessels and potentially cause low blood pressure. Make sure you read the pamphlets of any medicine your child is taking to make sure low blood pressure is not a symptom. If it is, and your child is suffering from it, contact your doctor immediately to change his or her medication.
• Other possible causes. Anemia, adrenal insufficiency, and shock can be related with low blood pressure in children.