Ways & How

How to Calculate Your Weeks of Pregnancy

How to Calculate Your Weeks of Pregnancy

Congratulations! You are probably so thrilled knowing that in a few months’ time you are going to be holding your little bundle of joy in your arms. I can just guess the questions that are going through your mind right now.  I’ll bet that one of the foremost questions is how to calculate your weeks of pregnancy so you’ll know when your baby is due. There is really no accurate way to tell, but there is a way to make a very educated guess on how far along you are in your pregnancy. By doing this, you will have an idea about when you are going to give birth. Aside from this, knowing which week you are currently in will also guide you in things that you should expect; the changes that your body will undergo and the development of your baby. With this as a guide, you can be sure you are doing the right things to make your pregnancy as healthy as possible. One very important thing you have to know is your “LMP” or your “last menstrual period.” This will determine when you are due and what week you are presently in. You have to look back and remember what week this is or what date was the first day of this last cycle before the pregnancy.

expound later on how to manually calculate your due date using the LMP. Visiting your obstetrician will also determine how far along you are. There are technologies that are used by doctors to aid them in approximating the number of weeks of each pregnancy. The most commonly used method is the ultrasound machine. You can get a close approximation using this machine even if you have irregular menstrual cycles or you simply don’t remember when your last menstruation was. However, it will still be better to use this method then to try to manually calculate to a better approximation.

  1. Get a calendar. It’s better to calculate with a calendar so you won’t have a hard time counting. It may even be a good idea to keep a journal for the whole duration of your pregnancy to keep track of things.

  2. The first thing is to know the first day of the last menstrual cycle. Look back at when the first day of your LMP was. Mark that date on your calendar.

    March 4 –   first day of LMP.

  3. From that date, add seven days.

    March 11 – LMP plus seven days.

  4. Determining the month of the date you calculated, go backwards for three months. This will give you your due date.

    Dec 11 – expected due date.

  5. To know which week you are in, the date in step 3 is the 1st week of your pregnancy; the next is the 2nd week of pregnancy, and so on and so forth until the 40th week.

You will also need to remember that the entire 40 weeks is divided by 3. Thefirst trimester is from week 1 until the 12th week. The second trimester will end at the 28th week, and thethird trimester goes to the 40th week.  This will aid you in knowing about the changes in your body and the fetus inside your womb that are occurring. This is an exciting time to educate yourself about all the important issues to focus on during your pregnancy especially for the sake of your child. Knowing how to calculate your weeks of pregnancy can give you good insight about pregnancy.  You will also know when to shop for your baby’s things since that’s what every mother-to-be is really looking forward to!


Your email address will not be published. Required fields are marked *

WaysAndHow is an online community of brilliant "how to" article authors who are wholly dedicated in bringing you the best and most in-depth ...

Follow us tweets

  • Knowing how to apply for Medicaid online is probably the best and most convenient ...

  • Student loan is one of the most difficult debts to pay off, largely because you accrue most ...

  • Most people would say that one of the hardest parts in starting a business is getting new ...

whats new

Contact Us


Address: Triple E Holdings Ltd. P.O. Box 23475 Richfield, MN 55423-0475 USA