Skip to content
First Trimester (Weeks 1 - 13) Week 13 of 40
Last reviewed by medical team: June 2026 Evidence-Based Care Check
Fetal Size Comparison

Week 13 Size: Lemon

About the size of a juicy lemon.

Length 7.4 cm 2.9 inches
Weight 23 g 0.8 oz

Relative Visual Scale

Solid circle represents your baby's size. Dotted circle shows the full-term week 40 size threshold.

Inside The Womb

Baby's Development

This is the final week of the first trimester. The baby has unique fingerprints! Vocal cords are beginning to form, and the intestines are moving from the umbilical cord into the abdomen.

Weekly Milestones

  • End of Trimester 1
  • Fingerprints Formed
Maternal Health

Your Body & Symptoms

Your energy levels are returning, and nausea is fading. Your libido might increase. The risk of miscarriage drops significantly after this week.

Common Symptoms this Week

Increased energy Higher sex drive Visible baby bump Leukorrhea (milky discharge)

Doctor & Care Recommendations

  • Start looking into maternity clothes or belly bands.
  • Discuss a birth plan draft with your partner.
  • Enjoy the boost in energy; do some light nesting or plan a babymoon.

Weekly Health Guides & Resources

Trimester Guide

First Trimester Guide

Read comprehensive clinical milestones, screening checklists, and developmental guidelines for this phase.

Explore Trimester →
Common Symptoms

Track & Relieve Symptoms

Learn why symptoms occur, home remedies, and clinical indicators for this week:

Pregnancy Nutrition

Food Safety Checklists

Verify safety statuses, listeria and mercury risks, and safe alternatives for:

Full Nutrition Guide →

Frequently Asked Questions: Week 13

💌

Get weekly pregnancy updates

Sign up to receive developmental milestones, medical symptoms, and expert tips tailored to your specific week of pregnancy.