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Your Due (Best Guess) Date

Okay, so you have an Estimated Due Date. You mark the date on your calendar. The date almost becomes famous as everyone wants to know about it and you can't help but countdown the days until that date arrives. But, is that magical date when your baby will arrive?

How is the Estimated Due Date calculated?

Let's start with where the estimated due date comes from...

In the early 1800s a German obstetrician by the name of Franz Karl Naegele is credited with the formula:

  • From the first day of your LMP

  • Add seven days

  • Subtract three months

  • Add a year

This formula assumes a 28 day cycle, ovulation on day 14 of that cycle, and a 280 day gestation. While 28 days may be the average length of a cycle, anywhere between 21 - 35 days is still in a normal range. Not every woman will ovulate on day 14, and even if those numbers lined up perfectly, each baby has their own unique gestational timeline for their growth and development.

Shift from Estimated Due Date to a Due Month

While the Estimated Due Date is excellent at giving us a general idea of the length of your pregnancy (can you image finding out you're pregnant in January and not knowing if you were going to have a baby in March or September?), it's far more accurate to use that date as a midpoint and know that anywhere from 2 weeks before to 2 (or 3) weeks after the estimated due date is still a normal range for a pregnancy.

Because there is so much attention on the estimated due date, our perception and even verbiage of other times is affected.

If you give birth before your due date? Your baby came early.

Was your baby born after the estimated due date? Oh, your baby was late.

The due date is seen as a magical date you expect your baby to be born. When in actuality, only about 5% of births happen on the EDD.

And if this is your first birth? The average length of pregnancy for first-time moms is 41 weeks and 3 days. That's ten days "late."

When the calendar reads your due date, your baby and your body may not be ready yet. And that's okay.

Tips as You Approach Your Due Date

You don't actually have to tell anyone your estimated due date.

You can say "late (fill in the month)" and leave it at that. If you do choose to give a date, it's always helpful to emphasize the estimated part of EDD, and follow up with "but we'll see when my baby and my body are ready."

It's okay to disconnect from social media and/or silence your phone.

You are not the only one counting down the days. Your family and friends are anxiously awaiting the arrival of your baby, and sometimes they get so excited they don't even realize that their questions and comments may be stressful (or even hurtful) to you. If you're getting the "BABY YET?!?!" texts or posts, feel free to share this image (or make your own to post).

You don't owe anyone an update.

Mentally plan for your pregnancy to go past your due date, but be prepared for your baby to be born before.

Babies, like wizards, are never early nor late, but arrive precisely when they mean to. You don't want to be so focused on one date that it takes away from enjoying the last few days of your pregnancy, or leaves you disappointed if it passes and you still don't have a baby in your arms. But you also don't want to be packing bags in active labor! So plan, but be prepared.

Go on a "Due date" date.

We know you are SO excited to meet this new member of your family. Your life is about to radically change, in the best way possible. And so are your relationships. Since statistically you will still be pregnant on your due date, we recommend setting aside time that day to do something fun and meaningful with a special person in your life. Are you never going to have this opportunity again? Of course not! Though it may feel that way for a while. But this is a perfect time to shift your focus from what has been on your mind for MONTHS and enjoy the person or people who are already in your life.

Babies also love to crash your plans, so planning this date just might bring you closer to meeting your baby.

We wish you well whatever day and what in whatever way you choose to birth your baby.


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