20 Jan 2023 | 5 min Read
Sudeshna Chakravarti
Author | 799 Articles
Throughout your pregnancy, your doctor may prescribe several different scans, tests, or procedures to ensure the proper growth and safety of your developing baby. Your ob-gyn usually recommends these tests based on your medical history, pregnancy-related complications, or genetics. One of the vital procedures that helps evaluate the growth and development of your baby is the CRL or crown-rump length measurement which helps measure your baby’s length in the uterus from top to bottom.
Read on, as we tell you more about CRL, what it tells about your baby, and how it is measured.
What is Crown-Rump Length (CRL)?
Crown-rump length or CRL is the measurement of the c-shaped embryo or the fetus from the top to bottom (crown to rump), excluding the limbs. In fact, this ultrasound scan is considered one of the most crucial measures for antenatal care during the first trimester and is usually performed between six and thirteen weeks of pregnancy.
The crown-to-rump length, also known as the greatest length (GL), is an accurate measurement in centimetres that helps determine the age of your baby. It also helps to evaluate accurate gestational age, which helps your doctor know more about your baby’s health, and also estimate your date of delivery better.
The crown-rump length scan will help your doctor learn about the early developmental stages of your baby. Some of the findings from this scan include:
While a CRL is vital in the first trimester, it might not be an accurate measurement during the later stages of pregnancy, as your baby grows in size and becomes more active. This is why other obstetric scans are performed to monitor your baby’s development and aspects such as abdominal circumference, fetal length, and fetal biparietal diameter.
Doctors use various formulations to evaluate crown-rump length, gestational age, and other factors. One of them is a simple math equation that helps determine your gestational age using the CRL. According to that equation, the gestational age equals to six weeks plus CRL multiplied by a number of days [GA = 6 weeks + (CRL X Days)]. In addition to this, the doctors also use the crown-rump length chart as a reference for their primary evaluation.
However, you should not always rely on charts determine CRL as they are only an approximation. Since every pregnancy is different, you may come across multiple dissimilarities while measuring CRL. Hence, it’s always better to consult your doctor and get regular reports regarding your baby’s health rather than relying on charts alone.
The crown-rump length is a crucial procedure during pregnancy that enables doctors to measure the length of the fetus. The ultrasound scan is done during the early developmental stage, and allows doctors to assess complications, track fetal heart rate, and monitor fetal growth. Doctors also use CRL to evaluate your gestation age and expected due date. There are many ways to calculate CRL, including a crown-rump length chart and mathematical formulations, but it’s better to consult your doctor for any queries rather than relying on the chart.
Varicose veins during pregnancy: What causes varicose veins during pregnancy and how do you deal with them? Tap this post to know.
Pregnancy night sweats: Experiencing night sweats during pregnancy? Here are some simple ways to deal with this concern.
Symphysis pubic dysfunction: What is symphysis pubic dysfunction and how does it affect your pregnancy? Tap this post to know.
Cover Image Credit: Freepik.com
A
Suggestions offered by doctors on BabyChakra are of advisory nature i.e., for educational and informational purposes only. Content posted on, created for, or compiled by BabyChakra is not intended or designed to replace your doctor's independent judgment about any symptom, condition, or the appropriateness or risks of a procedure or treatment for a given person.