First trimester
Pregnancy Week 13
Your baby is about the size of a lemon.
Size
lemon
Length
74 mm
Weight
23 g
Baby in week 13
Vocal cords are formed. Intestines move into the abdomen. The fetus has unique fingerprints.
What you may notice this week
End of first trimester. Energy improves for many. Nausea subsides.
Tips for week 13
- Celebrate making it through the first trimester
- Begin gentle prenatal yoga
- Eat protein-rich foods
Tools that pair with this week
Due Date Calculator
Estimate your delivery date by last period or conception date. Naegele’s rule plus cycle adjustments.
Week Tracker
See exactly how many weeks and days pregnant you are, plus your trimester and key milestones.
Contraction Timer
Tap once to start, once to stop. Tracks duration, frequency, and pattern over time.
Ovulation Calculator
Find your fertile window based on your cycle length. Plan or avoid with confidence.
Baby Name Generator
Filter by origin, style, length, and starting letter. Boys, girls, and unisex.
Growth Percentile
Plot your baby’s weight, length, and head circumference against WHO percentile curves.