13 Weeks Pregnant: Baby the Size of a Lemon

Week 13 is the last week of the first trimester. For many people this is when pregnancy starts to feel a little easier.

Your baby this week

Vocal cords: The vocal cords are forming.
Gut: The intestines, which grew partly into the umbilical cord, have moved back inside the abdomen.
Fingerprints: The patterns that will become unique fingerprints are starting to form.

Energy returning, and sickness fading for many.
A growing appetite. Eating for two is a myth; extra calories mostly come later.
Vaginal discharge increasing. Thin and mild-smelling is normal; itching or a strong smell is worth mentioning.
Clothes getting tight. A hair tie through the buttonhole buys time.

You have bleeding, or cramping pain low in your belly
You have sharp pain on one side, pain in the tip of your shoulder, or you feel faint
You're being sick so often you can't keep fluids down
You have a fever, or it burns or stings when you pee

If the pain is severe or you feel faint, call emergency services.

From week 14

The second trimester, often the most comfortable stretch.

Week 16

A routine checkup, often with results from earlier blood tests.

Add your own, then bring the list with you.

If things are easing, plan something small and normal together, like a walk or a meal out. A little ordinary life helps.

Enter your due date once and NUGA knows you're at week 13. The day before each appointment, it gathers what you've noted and the questions to bring.

This page draws on public guidance from:

General information, not medical advice. Every pregnancy is different, and your midwife or doctor knows yours. Last updated October 2026.