3 Ways to Calculate Pregnancy Age Correctly

Pregnancy is the period of time between conception and birth. During pregnancy, the fetus grows and develops in the mother's womb. Gestational age is measured in weeks, from the first day of a woman's last menstrual cycle to the current date. Gestational age needs to be calculated accurately so that pregnant women and doctors can monitor the development or growth of developing fetal organs. Let's find out 3 ways to calculate gestational age.

Each week of pregnancy is calculated from the first day of the last menstrual period. So, when you reach one week after your HPHT (First Day of Last Period) date, you are in the second week of pregnancy, and so on. A normal pregnancy can range from 38 to 42 weeks. Based on guidelines from the American Obstetrician and Gynecologists (ACOG), gestational age is divided into three trimesters as follows:

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• First trimester: 0-14 weeks of gestation
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• Second trimester: Gestational age 14-27 weeks
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• Third trimester: 27-42 weeks gestational age
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How to Calculate Pregnancy Age

Pregnant women are advised to know the gestational age so that they can estimate the baby's birth time and can prepare newborn supplies. If pregnant women already know the Estimated Day of Birth (HPL), then the baby's due date is in the range between 2 weeks before HPL or 2 weeks after HPL.

To find out how to calculate the gestational age, there are several ways that can be tried as follows:

1. Based on the First Day of the Last Period (HPHT)

The gestational age of pregnant women can be calculated in the most common way, namely based on the first day of the last menstruation. This will be easy to do for mothers who experience menstruation regularly every month. So that you can know exactly when the first day of your last menstruation (HPHT).

Fertilization that causes pregnancy usually occurs about 11-21 days after the first day of the last menstruation. Then, after knowing when the last menstruation of pregnant women can calculate HPL by adding 40 weeks from the first day of menstruation. Calculating the gestational age manually can be done with a formula. Here is the formula for how to calculate the gestational age of HPHT:

Record the first day of the last menstruation (HPHT)

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• Add one year
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• Add seven days
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• Rewind three months
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 For example, if the pregnant woman's HPHT is August 20, 2023, then the calculation becomes:

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•  August 20, 2023 + 1 year = August 20, 2024
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• August 20, 2024 + 7 days = August 27, 2024
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• August 20, 2024 - 3 months = May 27, 2024
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2. Based on Ovulation Date

Determining the gestational age can also be done by calculating the date of ovulation or the release of the egg. In general, ovulation occurs about 2 weeks after the first day of menstruation. This way of calculating gestational age is an accurate way, but unfortunately, not all women know when ovulation time is on their own.

3. Based on Ultrasound Examination

If moms have tried both ways but are still not sure. Moms can try to check the womb with the doctor through an ultrasound examination to calculate the gestational age. With this ultrasound, the gestational age will be more accurate especially if done early in pregnancy.

Ultrasound can be done since 5-6 weeks and calculate the gestational age with ultrasound between the 8th and 18th week of pregnancy. This ultrasound actually does not need to be done every month, but pregnant women are recommended to do an ultrasound at least 4 times, namely 1 time in the early trimester, 1 time in the second trimester, and 2 times in the last trimester. Usually, ultrasound in the final trimester is not intended to determine the age of the fetus but to monitor the baby's development and position before delivery.

Benefits of Pregnancy Screening

Calculating the gestational age is very important in order to know whether the growth and development of the child is optimal or not according to the gestational age. Here are a series of benefits obtained by pregnant women who calculate pregnancy suai:

Monitoring the development of the baby in the stomach

Every month the fetus in the womb grows and develops according to its age. So knowing the age of the fetus can monitor the progress of the pregnancy process and ensure the health of the mother and child.

Helps prevent pregnancy complications

Pregnant women are very susceptible to various diseases while pregnant. One of the diseases that usually afflict pregnant women is too high blood sugar and high blood pressure (hypertension). Both are very dangerous and life-threatening for both the pregnant mother and the baby. By having regular pregnancy check-ups, health problems can be detected and steps can be taken to address them early on.

Determining the method of delivery

Growth and development, gestational age, and the position of the fetus in the uterus determine the method of delivery. By knowing the gestational age, pregnant women can plan the delivery process, either normal or cesarean delivery.

Well, that's 3 ways to calculate the gestational age that is easily done by pregnant women and the importance of doing pregnancy checks. Pregnant women can monitor their pregnancy health regularly with the gynecologist if necessary. (Aq/MKK)