How Are Pregnancy Weeks Calculated – Due date Calculator

How Pregnancy Weeks Are Calculated?

Are you pregnant? Well, as exciting as it is, you need to calculate some things like how far along are you in your pregnancy and how pregnancy weeks are calculated. Here are some ways by which you can calculate that. 

Finding The Due Date Before The Ultrasound

You can roughly find out how many days or weeks you are along in your pregnancy, before going to the doctor for your first ultrasound. Although ultrasound is the real deal and the doctor will give you the right age of your baby and how long have you been pregnant, you can still make a rough estimate with your calendar. All you need to know is how many days has it been since you missed your period.

Calculate the date from the first day since your period is late till the present day and you have your approximate conceiving date, which you can turn into weeks and see how many weeks you are along. This can be quite rough, but the actual date is usually close to it, give or take a few days. 

What’s The Gestation Age?

The gestation age is the time between you conceiving the baby and the birth of the child. This doesn’t give the actual age of your child or how many weeks old is your child. You can guess and estimate the age of your baby through gestational age too. All you have to do is mark the day when your last period was missed and add 38 to 42 weeks in the date. This will give you the fetal age of the child. 

Fetal Age

Fetal age, as the name suggests, is the age of the fetus or the baby growing in your body. This is shorter than the gestational age and it can be more accurately found out by ultrasound. It’s very hard to find out the fetal age with a calendar and the information about your missed period. So, you need to go to your doctor and have an ultrasound done for the fetal age of the baby. 

Can Alterations Cause The Due Date To Change?

Once you find the due date, which is usually 290 days after you have missed your period, you have a due date that is approximate. Now, the due date you calculated is not set in stone. It can be farther than the date or before. This is all divine timing (or whatever you call that) and once the baby decides that it wants to come out, then there’s no stopping it. But having a due date can be a good marker so that you make necessary preparations for the hospital and book important appointments within that time frame. 


There you have it! Now you know how pregnancy weeks are calculated. This can be a good marker for you before you actually go to a doctor and get official results. 


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