How to Measure Fundal Height

By OBGYN Dr. Kenosha Gleaton

Have you heard your family, friends, or provider talking about fundal height measurement? Maybe you have an appointment coming up soon and are wondering what fundal height is and what it means for your pregnancy. OBGYN Dr. Gleaton explains what fundal height is, what it means, and how you can measure your fundal height at home. 

What Is Fundal Height?

Fundal height is a measurement of your belly during pregnancy that can help providers determine how far along a pregnancy is, the position of a fetus in the uterus, and if the fetus is developing correctly. [1-2] Fundal height is found by measuring the distance between the pubic bone and the top of the uterus. Most providers will begin measuring fundal height around the 20th week of pregnancy and will continue to measure fundal height at every prenatal checkup. [1-2] While there are other tests that can give providers more information, such as ultrasounds, fundal height measurement is a non-invasive and easy way to track your baby’s growth. [1] 

Fundal Height by Week

Fundal height will usually be measured for the first time around week 20 of pregnancy. This is because from about week 20/24 of pregnancy and beyond, your fundal height and gestational age should match, give or take 2 centimeters. [1-2] For example:

• Week 24: fundal height of 22-26 centimeters 
• Week 30: fundal height of 28-32 centimeters
• Week 35: fundal height of 33-37 centimeters

Fundal height should grow about 1 cm every week, or 4 cm every month. [3] It is possible for fundal height to decrease slightly after 36 weeks as a result of your baby settling into your pelvis and your body preparing for labor. [1] Fundal height is not an exact science either, and the position of your baby, your body, shape pre-pregnancy, and other factors may slightly influence your fundal height measurement. Your provider can run additional tests if they are ever concerned about your fundal height. 

Read my guide on pregnant belly stages → 

How to Measure Fundal Height at Home

To measure fundal height, you will need a soft tape measure that measures centimeters. You will also need to know how to locate your pubic bone and the top of the uterus. This can be tricky to find on your own, so don’t worry if your measurement ends up being higher or lower than expected. [1,3] 

To measure your fundal height, start by lying on your back with your legs in front of you. Place the zero marker at the top of your pelvic bone, and move the tape measure vertically up your stomach (along the linea nigra) until you reach the top of your uterus. [1,3] The distance between the two is your fundal height. 

Measuring fundal height may sound like a fairly easy task because it takes little equipment to complete, however, it’s important to note that measuring yourself or having someone who is not a medical professional measure you is not the same thing as seeing a healthcare provider. You should always see a professional for prenatal checkups, and try not to worry yourself if you attempt to measure your fundal height and get a number that seems high or low. It can be difficult to find the right areas to stop and start measurement, which can lead to skewed results. 

What Does Fundal Height Tell You?

Fundal height can give your provider valuable insight into your baby’s size, position, and growth. It may also be indicative of how much amniotic fluid is in the uterus. [1-2] If fundal height is within the expected range, it can help confirm that the fetus is growing as it should. If fundal height is off, it may be indicative of potential complications, such as fetal growth restriction, breech position, fibroids, etc. [1-2] 

Fundal Height Measuring Small

If your fundal height measurement is smaller than expected, there may be a few explanations [1]:

• Fetal growth restriction: Smaller than average fetus, may be caused by placenta abnormalities, high blood pressure, infections, or other factors. [4] 
• The fetus has dropped into the pelvis
• Oligohydramnios: Not enough amniotic fluid in the uterus
• You have a smaller frame or strong abdominal muscles

Fundal Height Measuring Ahead

If your fundal height measurement is larger than expected, there may be a few explanations [1]:

• Multiple pregnancy
• Incorrect due date
• Uterine fibroids
• Polyhydramnios: Excess amniotic fluid in the uterus
• Fetus is breech
• Fetal macrosomia: Larger than average fetus, often due to diabetes or obesity
• You are overweight or obese

It is also possible that there is no real cause or a cause not listed above. If you are concerned about your fundal height, you should speak with a healthcare provider. They will be able to run additional tests if necessary to determine if there is a cause for concern.

Is Fundal Height An Accurate Measurement?

Measuring fundal height is an easy, non-invasive, and inexpensive way for providers to track the growth of a fetus. Fundal height may be the first indication of growth problems or an issue with a baby’s position. Unfortunately, there are no methods that are 100% accurate when measuring a baby’s size in utero, and it’s common for fundal height to vary by 1-2 centimeters. [1-2] However, it is still a useful tool for assessing fetal growth throughout the second half of pregnancy. Your provider will discuss any additional testing options with you if there is a reason to be concerned. Most people will also have one or two ultrasounds during their pregnancy, which can provide additional information. [5] 

Support Healthy Fetal Growth

If you are pregnant or are hoping to conceive soon, you can promote healthy fetal growth and reduce the risk of some complications, such as certain birth defects and fetal growth restriction. Research shows that the following can encourage a healthy pregnancy [6-7]:

• Take a comprehensive prenatal vitamin that includes folate
• Avoid use of alcohol, tobacco, or drugs
• Avoid exposure to toxic substances
• Eat a safe and balanced diet
• Limit caffeine 
• Stay physically active
• Maintain a healthy weight
• Get regular prenatal and dental care
• Prevent infection
• Manage stress

You should discuss these methods with your provider as well, as not all of these recommendations may be right for you. Wishing you a happy and healthy pregnancy! 

Natalist Pregnancy Products

As a new, soon-to-be, or veteran parent, we know that you want the best for your family. The path to parenthood is often full of surprises, bumps in the road, and can bring forward many questions. At Natalist, you can trust that you’re getting high-quality, evidence-backed, sustainable, and beautiful products and resources. Support your nutrition with vitamins and supplements, learn more about your body with our books and home tests, or pamper yourself with some self-care. Want to keep reading? Head over to the Natalist blog. 

Dr. Kenosha Gleaton is board-certified in gynecology and obstetrics and is the Medical Advisor of Natalist. She received her MD from MUSC and completed her residency at Carolinas Medical Center in Charlotte, NC.

Dr. Gleaton is passionate about women, health equity, and mentoring. She is the CEO of The EpiCentre, an OBGYN spa-like practice, and is a Clinical faculty member of Charleston Southern University.  She is also a member of the American College of Obstetrics & Gynecology, the American Association of Gynecologic Laparoscopists, and the American Association of Professional Women. 

References:

1. Fundal Height. Cleveland Clinic. January 2022. https://my.clevelandclinic.org/health/diagnostics/22294-fundal-height
2. Tobah Butler Yvonne. What's the significance of a fundal height measurement? Mayo Clinic. December 2022. https://www.mayoclinic.org/healthy-lifestyle/pregnancy-week-by-week/expert-answers/fundal-height/faq-20057962
3. White LJ, Lee SJ, Stepniewska K, et al. Estimation of gestational age from fundal height: a solution for resource-poor settings [published correction appears in J R Soc Interface. 2015 Dec 6;12(113). pii: 20150978. doi: 10.1098/rsif.2015.0978]. J R Soc Interface. 2012;9(68):503-510. doi:10.1098/rsif.2011.0376
4. Chew LC, Verma RP. Fetal Growth Restriction. [Updated 2023 Aug 8]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK562268/
5. Ultrasound in Pregnancy. Cleveland Clinic. September 2022. https://my.clevelandclinic.org/health/diagnostics/9704-ultrasound-in-pregnancy
6. What can I do to promote a healthy pregnancy? NIH Office of Communications. January 2017. https://www.nichd.nih.gov/health/topics/preconceptioncare/conditioninfo/healthy-pregnancy
7. Horsager-Boehrer, Robyn. New study suggests diet, stress management might reduce fetal growth restriction risks. UT Southwestern Medical Center. December 2021. https://utswmed.org/medblog/diet-stress-effects-on-baby/