Bloodwork for One-Year-Olds: 2 Tests Kids Need

Your baby is already a year old! This feels huge. With turning one comes a doctor’s appointment. Also called a well child check or a preventive visit, this appointment is a busy one. Many parents ask which lab tests are done at one year-old’s appointments. This post reviews the recommended bloodwork for one year-olds, why the lab tests matter, and what might happen if the results are not normal. I’ll also go over what else is included in a one year-old’s doctor appointment.

Bloodwork for one year-olds.

At age 12 months, two blood tests are recommended for many kids: lead and hemoglobin levels. 

Hemoglobin screens for anemia. 

The hemoglobin blood test screens for anemia/lower blood counts. Sometimes, this may be done before age 12 months. (Some babies may have the screening test at 9 months). But, if it hasn’t been done already, the American Academy of Pediatrics recommends it at age 1 year. 

Why would hemoglobin be low in a one-year-old?

There are several causes for a low hemoglobin, but the most common cause in toddlers is not enough iron.

If a parent is told the hemoglobin is low, there are a few possible options a pediatrician may suggest:

• Prescription iron supplements and recheck the levels in about a month. A pediatrician may consider this only after a thorough conversation and physical exam. (Too much iron can be dangerous, so follow directions precisely and store any supplements out of reach).
• Have the family make an extra effort to increase iron in the diet, while also limiting drinking cows milk to about 16 ounces a day. Then, recheck hemoglobin levels.
• Get additional bloodwork. If a low result isn’t clearly explained during the appointment with conversation and physical exam, then doctors need to check for other explanations. Usually, this means another lab draw.

 Lead blood testing checks for lead exposure in one year-olds.

Lead is a toxic metal that can cause brain damage, especially in kids. So, many toddlers need to be tested at least once. This does not necessarily include every child. Their pediatrician will be able to tell if a lead test is needed.

This blood test helps find kids who have been exposed to lead. Sometimes families already know if their kid is at risk. For example, maybe a family member has a job that involves working with lead. Or, their house may have been built before 1978 when lead was commonly found in paint.

On the other hand, many times a family does not know their child has been around lead. If a lead blood level comes back high, they can then investigate and find where the lead is coming from.

Lead can be found many places.

Lead can be found in old paint, some toys, cosmetics, and older plumbing systems. Even candy can be contaminated with lead. Air pollution is a source too. (See this post for lowering risks of air pollution when outdoors). Babies and toddlers explore the world with both their hands and mouths. If they’ve been playing on a floor with old paint flakes, it can be enough to expose them and cause higher lead blood levels.

What is a normal level of lead on a bloodwork in toddlers?

Strictly speaking, any amount of lead is not normal. Based on a child’s results, their doctor can explain what, if anything needs to be done. The current “reference level,” for labs is 3.5 micrograms per deciliter (mcg/dL). This simply means that most kids (97.5% to be exact) have lead levels below 3.5 mcg/dL.

What happens if the lead level in a one year-old’s bloodwork is too high? 

Often, if a lead level is too high, their physician and local health officials may help in identifying the cause, especially if it isn’t an obvious exposure. Then, the child’s doctor, the health department (for example), and the family, work together to lower the exposure. And, yes, another blood test is often in the future, to recheck and make sure the number isn’t still going higher.  

Lead levels after age one.

Lead levels may also be checked after age one, depending on each child’s risk and their community. In my experience, exposure is much more common in some regions of the country than others.

How are labs drawn for a one year-old’s bloodwork?

Now that a parent knows which bloodwork to expect, the bigger question is how does a lab get that blood to analyze? This varies a lot depending on individual offices and labs. Generally, there are two possibilities.

1. A fingerstick is a quick poke, usually in part of a child’s finger. It takes a few seconds to get the blood sample.
2. A “venous draw” means the technician finds a vein and gets a blood sample that way. This process is more precise and can take a bit longer. The lab may use a vein in a child’s arm or hand. There are absolutely other reasonable places to draw blood, but arm and hand seem to be more common.

Some offices will start with a fingerstick for the hemoglobin test. Some of these clinics have a machine that can give the result within a few minutes. If it is not normal, they may decide to go ahead with a venous draw for further testing. Parents can always call ahead to see which process their child’s office follows. Sometimes the bloodwork (especially the finger pokes) can be done in the office. Sometimes, it all needs to be done in a lab at another location.

Some kids need additional bloodwork at age 1.

Lead and hemoglobin are the most common blood tests for one year-olds. However, they’re not the only tests. Some kids need additional lab work. I mention this so it’s not a surprise if there are more pokes than anticipated! By the end of the visit, a child’s doctor can usually explain what else is needed and why. I always suggest parents ask when any lab results are to be expected. This way, parents themselves can be proactive in getting answers.

A one year-old check up is more than just bloodwork.

It’s not all pokes! A one year-old’s regular well visit includes more than the lab tests. Their physician will also want to check growth, development, and answer a parent’s questions.

Here is a more detailed list of what a typical visit includes:

• Vitals including head measurement, length, weight, heart rate, and temperature,
• Review of growth (looking at growth charts) and development
• Discussion of: milestones, feeding, and behavior. (Looking ahead? See this post on 18-month milestones).
• Review of toddler safety (For example, this may be a reminder to keep one year-olds in a rear-facing car seat. Or, it can include child-proofing, especially in the kitchen).
• Physical exam. This includes: listening to chest, heart, lungs, and belly. It also includes examining ears, eyes, nose, mouth. A physician may also check the head and neck (for the child’s “soft spot” and lymph nodes). They also examine the abdomen, genitals, joints (including hips), back, and skin. During the exam, the pediatrician also notes how the child is moving, interacting with their family, and sounds they may make (babbling, for example).
• Vaccines. Most 12-month-old preventive visits include vaccines. The exact combination of vaccines can vary slightly from one clinic to another. This is because many are recommended between ages 12 and15 months, so some offices opt to give some at age 15 months, instead of all at age one year. Either way, some of the vaccines after age 1 year are usually new to the child (including vaccines for Measles, Mumps, and Rubella, Hepatitis A, and Varicella). If it’s flu season, the flu vaccine can often be given with the other routine immunizations.

Summary: The one year old visit usually includes one or two blood tests (hemoglobin and lead levels), a thorough exam, vaccines, and an evaluation of development.

It’s a great opportunity for parents to check in with the pediatrician to see how their one year-old is doing. They can get questions answered as well as have the bloodwork to make sure their child is healthy inside and out.

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Maya M. Mahmood, D.O., FAAP is a board-certified pediatrician and mom. She is passionate about parents having evidence-based information to help their families be healthier.

Photo by National Cancer Institute on Unsplash