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Pregnancy Week by Week

Our week by week pregnancy guide provides expectant parents with everything they need to know about baby's growth and development, including medically-accurate illustrations of fetal development, information about the changes going on for mum and baby, and even tips and fun facts! Click on one of the weeks below to get started.

You may be confused about how many weeks are in each trimester, and when each trimester starts and ends. There are actually several different methods to calculating the dates of trimesters, which is why you may see different websites list 12 or 13 weeks as the end of the first trimester. We use the gestation method, which counts the 40 weeks of gestation starting with the first day of your last period. The other popular approach is the baby development method which ignores the two weeks pre-conception and therefore is a 38 week cycle where the second trimester starts at week 12.

First Trimester

Second Trimester

Third Trimester

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