The first trimester is the first 3 months of pregnancy which is marked by the first day of your last menstrual period, until the end of week 12. You’ll likely be halfway through your first trimester before you even know you’re pregnant!
Your baby will do the most rapid growth during these 3 months, growing from a single cell and increasing by 10,000 times its size in the first 7 weeks alone, to 1.6cm in length and around 1 gram in weight at the 7-week mark. Evolving through the stages of zygote, blastocyst, embryo and finally to fetus at the end of the trimester. During this time, it develops all its features, bones, organs, muscles, nervous system, brain, and even a tiny beating heart.
You’ll likely feel pregnant before you look it, with your hormones rising, the dreaded early symptoms will pop their heads up - tender breasts, nausea, and fatigue, or maybe you’ll feel none of them! Every pregnancy is different, but our week-by-week guides should help you to understand what's happening inside you, as well as common symptoms and help to guide you through the next steps.
You got this!
