Syncry
Begin
PREGNANCY WEEK BY WEEK

4 weeks pregnant

About the size of a poppy seed

2mm

This week

A tiny seed with an enormous plan.

  • The first blueprint
    The neural tube is forming: the very beginning of the brain and spinal cord.
  • A heart in the making
    The cells that will become the heart are already organising themselves.
  • The lifeline begins
    The placenta and umbilical cord are starting to build the supply line that will feed your baby for months.

Written against the NHS week-by-week guide. A picture, not a measurement: every baby grows at their own pace.

THIS WEEK’S QUESTION, FOR THE TWO OF YOU

“How did you find out, and what was the very first thing you felt?”

Every Sunday, Syncry asks you both one question like this. You each answer in your own words, and the answers become your book.

Get next Sunday’s question

Your first month is free. No card needed to start.