During pregnancy, healthcare providers commonly use fundal height to monitor a baby’s growth. This simple, non-invasive screening tool helps track pregnancy progression and identify potential deviations.
Understanding Fundal Height
Fundal height is a measurement in centimeters from the top of the pubic bone to the top of the uterus, known as the fundus. Healthcare providers perform this measurement during prenatal appointments, typically starting around 20 to 24 weeks of gestation. To take the measurement, a pregnant person lies on their back while the provider uses a flexible tape measure. This screening tool assesses fetal growth and monitors changes in uterine size over time.
Expected Measurement at 28 Weeks
At 28 weeks of pregnancy, the fundal height is typically expected to be around 28 centimeters (cm). This follows a general guideline where the fundal height in centimeters closely corresponds to the number of weeks of gestation. This correlation is usually observed from about 20 weeks until 36 weeks of pregnancy.
A normal variation for this measurement is generally considered to be plus or minus 2 cm from the gestational week. For instance, at 28 weeks, a measurement between 26 cm and 30 cm would typically be within the expected range. It is important to remember that this is an average, and individual measurements can vary due to several factors.
Interpreting Fundal Height Deviations
When a fundal height measurement deviates significantly from the expected range, it signals a need for further evaluation, but it does not automatically indicate a problem. A measurement that is larger than expected could be due to a larger baby, an excess of amniotic fluid (polyhydramnios), or carrying more than one baby. An incorrect estimated due date is also a common reason for a seemingly high measurement.
Conversely, a fundal height measurement that is smaller than expected might suggest a smaller-than-average baby, too little amniotic fluid (oligohydramnios), or an incorrect due date. Factors such as the pregnant person’s body shape, uterine fibroids, or the baby’s position can also influence the measurement’s accuracy.
What Happens Next
If a fundal height measurement falls outside the typical range, healthcare providers usually recommend additional assessment. The most common next step involves an ultrasound to gain a more precise understanding of the situation. An ultrasound can help confirm the gestational age, accurately assess fetal growth, and evaluate the volume of amniotic fluid around the baby.
This further assessment helps determine the underlying cause of the deviation and whether any specific concerns need to be addressed. It is important for individuals to communicate with their healthcare provider and follow their guidance, as they can provide reassurance and clarify the next steps. These follow-up procedures are designed to ensure the well-being of both the pregnant person and the baby.