Week 5: A Tiny Heart Starts to Beat

Week 5 baby size comparison

Your baby is now about the size of a sesame seed.

Avg. Length: 0.2 cm

(Crown to Rump)

Your Baby This Week

Incredibly, your baby's tiny heart tube is forming and starting to beat! Now the size of a sesame seed, the embryo has three layers that are building the foundations for all of its organs. The neural tube, which becomes the brain and spinal cord, is developing rapidly. A primitive umbilical cord is also taking shape, preparing to connect to the growing placenta.

Your Body This Week

A missed period is a big clue, and pregnancy hormone (hCG) levels are now high enough for a positive home test! It's completely normal to feel a mix of excitement and anxiety with the news. If you feel worried, don't hesitate to share your feelings with your doctor. You may also begin to feel 'under the weather' as early symptoms kick in.

Tips for Your Partner

Now that it's official, shower her with support! Offer to go with her to the first prenatal visit. Organizations like the Mayo Clinic recommend that pregnant women avoid changing cat litter to prevent toxoplasmosis, so this is a great chore for partners to take over