Pregnancy Week 1

Learn what's happening in week one, even before your baby is conceived, and find out why your due date is calculated from this point on.

Your Developing Baby

In the first week of your pregnancy, there's no baby--yet! But a growing fetus will be there very soon.

Watch Your Baby's Growth

Sperm Meets Egg: Weeks 1 to 3 of Pregnancy
Sperm Meets Egg: Weeks 1 to 3 of Pregnancy

Something magical is about to happen! Watch as the ovulation process occurs, and then millions of sperm swim upstream on a quest to fertilize an egg.

Your Changing Body

You probably don't know you're pregnant (or rather, about to be!), but you're well on your way. Your conception date is considered to be two weeks after the last day of your last menstrual period.

You won't notice anything yet, but if you're trying to conceive and think it's about to happen, nix alcohol and smoking and replace those vices with prenatal vitamins.

Your Pregnancy Calendar

Organize your doctor's appointments, save your ultrasound photos, and more--all in one place!

Ask Parents About Week 1

We've got answers to your questions from experts and parents who've been there.

See All Questions or Ask Your Own

Everything in Pregnancy Week 1

More About Your Pregnancy in Week 1

Your Baby

Your Body

Your Self

  • Your Partner: How Men React to Pregnancy

    Your partner may not react to your good news in the same way as your girlfriends. Find out why sometimes there is a difference -- and t...

  • Telling Your Partner

    Time to share the good news with your partner? Read this before you make the big announcement for solid pointers and helpful advice.

Diet & Exercise

  • Smoking and Alcohol Use

    Smoking and drinking alcohol during pregnancy is a big no-no. But do you know why? Find out what this can do to your baby.

  • Prenatal Vitamins

    Taking a prenatal vitamin is an essential part of early pregnancy.

Q & A