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Second Trimester (Weeks 14 - 27) Week 21 of 40
Fetal Size Comparison

Week 21 Size: Carrot

About the length of a long carrot.

Length 26.7 cm 10.5 inches
Weight 360 g 12.7 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

The baby's movements are transitioning from reflex-like flutters to deliberate kicks and nudges. The baby's taste buds are developed, and they can taste the flavors of the foods you eat through the amniotic fluid.

Weekly Milestones

  • Taste Buds Functioning
  • Deliberate Movement
Maternal Health

Your Body & Symptoms

You might feel generally comfortable, but stretch marks may start appearing. Varicose veins and spider veins can show up due to pressure on pelvic veins.

Common Symptoms this Week

Kicks and nudges Stretch marks Varicose veins Increased appetite

Doctor & Care Recommendations

  • Wear support hose if you develop varicose veins.
  • Eat a wide variety of healthy foods to introduce different flavors to your baby.
  • Avoid standing for long periods without moving.
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PregWeeks

CHECKLIST

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Weekly Health Guides & Resources

Trimester Guide

Second 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 21

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Evidence-Based Clinical Sources for Week 21

PregWeeks is dedicated to medical transparency. Every milestone, symptom tip, and fetal development guideline for Week 21 is sourced directly from clinical guidelines published by leading obstetric authorities. Read more about our editorial methodology on our Medical Sources page.

Prenatal Diagnostic Testing for Genetic Disorders (Practice Bulletin No. 162)

ACOG

Clinical recommendations for mid-pregnancy screening options, including the anatomy ultrasound scan commonly scheduled between weeks 18 and 22.

View Clinical Guideline

Gestational Diabetes Mellitus (Practice Bulletin No. 190)

ACOG

Practice standards for screening and diagnosing gestational diabetes mellitus (GDM), typically scheduled between weeks 24 and 28.

View Clinical Guideline

Implementing a Gestational Diabetes Screening Protocol (Committee Opinion No. 798)

ACOG

Standardized protocols for glucose screening tests to detect gestational diabetes and optimize maternal-fetal metabolic health.

View Clinical Guideline
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🏥 Medical Disclaimer

PregWeeks is an educational planning tool and does not provide clinical diagnoses or medical advice. Always consult your obstetrician or healthcare professional for health concerns.