Pregnancy week by week · trimester 1
🍑 13 weeks pregnant: your baby is about the size of a peach
At 13 weeks pregnant, your baby is about the size of a peach, and fingerprints are beginning their unique pattern. You are nearly into the second trimester.
Your baby this week
Your baby is roughly the size of a peach. Tiny, completely unique swirls are forming on their fingertips, the beginnings of fingerprints that will be theirs for life. Vocal cords are developing, and the bones of the arms and legs are getting longer and stronger. Your baby can put a thumb near their mouth, and is practising swallowing small sips of amniotic fluid. The intestines, which grew partly into the cord, are now settling back inside your baby's tummy.
You this week
You are on the edge of the second trimester, and many mums feel a little more like themselves. Sickness may be fading, and appetite returning. You might notice your bump beginning to show, especially later in the day. Some mums get a stuffy nose or the odd nosebleed because of extra blood flow. Your sex drive may change in either direction. Every body does this its own way.
Kind things to do this week
- Start sleeping on your side if you can, so it becomes a comfortable habit before later pregnancy.
- Look for a well-fitting maternity bra and comfy waistbands.
- If you have not had your dating scan yet, check it is booked before 14 weeks.
Appointments around now
If you have not had it yet, your dating scan should happen by 14 weeks. Your next routine appointment is usually around 16 weeks.
Questions to ask your midwife
- What exercise is safe for me in the second trimester?
- When should I book antenatal classes?
When to call your midwife or maternity unit
Please call your GP, midwife or NHS 111 if you have any bleeding, tummy pain that does not settle (especially low down on one side), or you are being sick so often you cannot keep fluids down. You are never wasting anyone's time.
OBubba from bump to baby
Follow your pregnancy week by week, free.
OBubba is free through pregnancy, with a weekly update, kick counting and contraction timing. On the day your baby arrives, the same app becomes your baby tracker.
Questions
When does the second trimester start?
The second trimester runs from week 14 to the end of week 27. Week 13 is the last week of the first trimester.
Why do I get nosebleeds when pregnant?
Extra blood flow and hormones can make the small blood vessels in your nose more delicate. They are usually harmless, but tell your midwife if they are frequent or heavy.
Not sure how far along you are? Use the due date calculator.
Sources
OBubba gives general information. It is not medical advice and does not diagnose anything. Your midwife and maternity unit are always the right people to ask, any time of day or night.