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1 Week Pregnant: Week-by-Week Guide

1 Week Pregnant: Week-by-Week Guide

Surprise! This week is the start of an amazing journey. Find out what happens during the first week of pregnancy, plus smart steps you can take to give you and your baby the best start possible.

  • Which trimester is 1 week pregnant? First trimester
  • How many weeks of pregnancy are left? 39 weeks
  • How many months pregnant am I? You’re considered to be in the first month.

Your first week of pregnancy is underway. Enjoy it, as week two is on the horizon!

One of the most exciting things about pregnancy is how many changes you’ll experience with your little one over the span of just seven days! Here are some tips and tricks to keep on top of all that’s happening.

What happens during the first week of pregnancy?

  • You’re on your period: Because it’s hard to pinpoint the exact date of conception, most OBs start counting your pregnancy from the first day of your last period, also known as LMP (last menstrual period). Consider this week one of your pregnancy journey.
  • Your body is preparing for baby: Your uterine lining is shedding, releasing last month’s unfertilized egg, and will start preparing for this month’s egg to be fertilized.

What’s going on with baby?

Well, nothing quite yet. Conception won’t happen for about another two weeks or so. Right now, your body is setting the stage for something magical to happen.

How big is your baby at 1 week pregnant?

At week one of pregnancy, your baby is 0 ounces, 0 inches—that’s because they haven't been conceived yet. But get ready. Once conception happens, your baby will grow and develop quickly over the next three trimesters.

Pregnancy symptoms week 1

Since you’re not actually expecting yet, there are no symptoms. But if you’re hoping to be pregnant soon, it’s time to get your body baby-ready. Start focusing on proper nutrition, and adopt an exercise plan if you haven’t done so already. Believe us, it’s a smart move.

Prepare for your first week of pregnancy

Help your baby even before the first week of pregnancy. Taking a prenatal multivitamin with folic acid before becoming pregnant can reduce the risk of congenital disabilities to your baby’s brain and spine. Plus, vitamins are an easy way to get essential nutrients you both need from the very start.

How to calculate your due date

Once you get that positive pregnancy test result, you can start calculating the estimated arrival of your bundle of joy. Here are two common ways:

  • Determine the first day of your last menstrual cycle and count forward 40 weeks.
  • Subtract three months from the first day of your last period and add on seven days.

An easy-to-use pregnancy due date calculator can help you get a better understanding of your pregnancy timeline.

Join Enfamil Family Beginnings

You’re one week pregnant, and even though you’re not officially expecting, you can start preparing for all the excitement with Enfamil Family Beginnings. It’s the perfect resource for new and expecting moms. Save on Enfamil products, track your bump and baby’s growth, and get helpful articles each week relevant to your journey. Join now for up to $400 in free gifts.