First trimester

Week 5: A positive test

You’re 5 weeks pregnant — about 35 weeks to go. Your baby is roughly the size of a sesame seed.

5 of 40 weeks

Size of

a sesame seed

Length

0.3 cm

0.1 in · crown to rump

Weight

Your baby this week

The neural tube — the foundation of the brain and spinal cord — is forming, and a primitive heart begins to fold and flutter. Major organ systems are being mapped out.

Your body & how you might feel

Pregnancy hormones surge, and early symptoms can arrive fast. This is a great time to book your first prenatal appointment.

Common symptoms at week 5

  • Fatigue
  • Nausea
  • Frequent urination
  • Sore breasts

This week’s tip: Call your provider to schedule your first appointment — most are at 8–10 weeks, and booking early secures your spot.

A gentle reminder: This is an estimate, not medical advice. Dates and figures are general guidance — every pregnancy is different. Your healthcare provider’s assessment, especially from an early ultrasound, always takes priority. Always speak with your provider about your pregnancy.

Week 5 FAQs

How big is the baby at 5 weeks?

At 5 weeks pregnant, your baby is roughly the size of a sesame seed, about 0.3 cm (0.1 in) long. These are typical averages — every baby grows at its own pace.

How many months is 5 weeks pregnant?

5 weeks pregnant is about 1 month, in the first trimester, with about 35 weeks to go until your due date.

What are common symptoms at 5 weeks?

Common experiences around week 5 include fatigue, nausea, frequent urination, sore breasts. Symptoms vary widely — contact your provider if anything worries you.