← All weeks

Week 13

Trimester 2

Days 12+0 to 12+6

Week 13 of 4033%

Baby is now the size of a peach

Welcome to Week 13 and the beginning of the second trimester. For many parents, this feels like a fresh start. The first trimester is behind you, and many of the challenges of early pregnancy may begin to ease. Your baby continues to grow rapidly and now has all major organs in place. Over the coming months, those organs will mature and become more sophisticated. You are officially entering one of the most enjoyable stages of pregnancy for many families.

Length

7–8 cm

2.8 in–3.1 in

Weight

20–30 g

44.1 lb–66.1 lb

Development highlights

  • check_circleThe body is beginning to catch up with the head, making your baby look more proportionate.
  • check_circleFingerprints are forming — the unique patterns your child will carry for life are beginning to develop.
  • check_circleMany bones that started as soft cartilage are beginning to harden and strengthen.
  • check_circleYour baby may now be able to make tiny facial expressions — frowning, squinting, and grimacing — as muscles and nerves develop.
  • check_circleThe intestines continue moving into proper position, and the digestive system is practicing movements for after birth.

This week's milestones

  • check_circleUnique fingerprints beginning to form.
  • check_circleSkeleton beginning to harden.
  • check_circleFirst tiny facial expressions developing.
  • check_circleBody becoming more proportionate.
lightbulb

Fun fact

Your baby's fingerprints are already becoming unique and will remain unique for the rest of their life.

Weekly checklist

  • Continue prenatal vitamins.
  • Stay hydrated.
  • Eat balanced meals.
  • Stay active if you feel well.
  • Attend scheduled appointments.
  • Celebrate the start of the second trimester.

Frequently asked questions

Is the second trimester really easier?

For many people, yes. Energy often improves and nausea may decrease, although every pregnancy is different.

Is round ligament pain normal?

Yes. Mild stretching or pulling sensations are common as the uterus grows, especially when changing position quickly.

Why do I suddenly feel better?

Many pregnancy hormones begin stabilizing, and the placenta is taking over more of the work of supporting the pregnancy.

Can I start buying baby items?

Absolutely. Many parents begin planning and shopping during the second trimester.

health_and_safety

Medical information disclaimer

The content on this page is provided for general informational and educational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment.

Always consult your GP, midwife, health visitor, paediatrician, or other qualified healthcare provider before making decisions about your health or your child's health and development. Never ignore or delay seeking professional advice because of something you have read on BabyScout. If you think there is a medical emergency, call 999 (UK) or your local emergency services immediately.