17/Aug/2026
Your Pregnancy Week by Week
The Complete Guide to the First Trimester (Weeks 1–13)
“One day you’re staring at a positive pregnancy test. A few weeks later, your baby’s heart is already beating.”
Pregnancy is extraordinary partly because so much happens long before anyone else can tell you’re expecting. Over the first trimester, your baby grows from a single fertilised cell into a tiny human with developing organs, arms, legs, fingers and toes, while your own body adapts in remarkable ways: hormones climbing, blood volume rising, the uterus expanding, the placenta forming. It’s no wonder these early weeks can feel amazing and overwhelming at once. This guide walks through what happens week by week, which changes are normal, and when it’s worth contacting your healthcare provider.