Being 5 weeks pregnant can be a pretty eventful time. After missing your period, you might have taken a pregnancy test and realized that you’re expecting. This can be both exciting and scary at the same time. It’s a monumental change, and it’s very normal to have questions.
While you might have only had a few days to process the idea of being pregnant, you’re actually in your second month of pregnancy. This is because your gestational age is calculated from the first day of your last period (the fetal age is calculated from fertilization).
Your baby may be too small to see or feel, but you might already be experiencing the emotional and physical changes of pregnancy. It can be comforting to understand what’s happening with your body and your baby at this time. So, keep reading to learn about early pregnancy symptoms and what else you can expect at 5 weeks pregnant.
Your baby at 5 weeks pregnant
Developing a neural tube
Your baby is tiny at 5 weeks pregnant — the size of a sesame seed, in fact. However, even at this very early stage of pregnancy, your baby’s nervous system is starting to develop. When you’re around 5 weeks pregnant, your baby will develop a flat, ribbon-like tube called the neural tube, which will eventually become their brain and spinal cord.
As their neural tube starts to develop, their heart is also starting to form. By 5 weeks of your pregnancy, the foundations for your baby’s organs are also in place. They’ll even have some tiny blood vessels so that blood can begin to circulate.
When you’re around five and six weeks pregnant, your baby’s eyes will have developed. Two tiny growths will stem from the neural tube and develop into cup-like structures that connect your baby’s optic nerve to their brain. However, they won’t look like eyes as we know them for many months to come. In fact, your baby won’t open their eyes in the uterus for the first time until around 28 weeks.
How big is a baby at 5 weeks?
Length (crown to rump): Around 0.08 in. (2 mm)
Size: Equivalent to a sesame seed
All measurements are approximate and vary within the normal range.