ParentSide
Join for free
First trimester

5 Weeks Pregnant

Very early pregnancy

This week your baby is around the size of a sesame seed.

How your baby is developing

  • Tiny structures are starting to form around this stage.
  • The earliest foundations of the heart and nervous system are developing.

What may be happening in your body

  • The first real waves of tiredness can arrive now, sometimes hitting early in the day.
  • A faint, on-and-off queasiness may start this week, often before it settles into any pattern.
  • Many still feel much like usual for now — early symptoms often haven't ramped up yet.

How you may be feeling

  • A positive test can make it all feel suddenly real, bringing relief and apprehension together.
  • Some people find themselves quietly counting the days toward a first appointment or scan.
  • It's common for worry to come and go before you've had any check-up to reassure you.

Worth remembering

Feeling few symptoms does not mean anything is wrong; every early pregnancy differs.

A closer look

Symptoms often build slowly

Around five weeks, early signs like tiredness or mild queasiness may just be starting for some, while others notice very little yet — and that difference is completely normal. How many symptoms you have, or don't, isn't a measure of how the pregnancy is going. For many, symptoms build over the coming weeks rather than arriving all at once.

Something you can do this week

Resting when you can and eating what feels manageable can help.

What comes next

Nausea and a heightened sense of smell become more common for many next week.

Professional support

Services ParentSide defines for this stage. Each page explains what the service covers and which professionals are approved to provide it.

All ParentSide services →

Sources and updates

Sources

Last reviewed:
This content is based on estimated averages and general information; it does not replace medical advice. If you are concerned about yourself or your baby, speak with a qualified healthcare professional.

All pregnancy weeks →