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Second Trimester (Weeks 14 - 27) Week 18 of 40
Fetal Size Comparison

Week 18 Size: Artichoke

About the size of an artichoke.

Length 14.2 cm 5.6 inches
Weight 190 g 6.7 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 ears stand out from the head, and they can hear external sounds. The baby may be startled by loud noises. A protective coating called vernix caseosa begins to cover the skin.

Weekly Milestones

  • Vernix Coating Starts
  • External Hearing Active
Maternal Health

Your Body & Symptoms

Your uterus is now about the height of your belly button. You might feel your baby kick, roll, or punch more clearly now.

Common Symptoms this Week

Clearer fetal movements Dizziness Swollen feet or ankles Leg cramps, especially at night

Doctor & Care Recommendations

  • Elevate your feet whenever you sit down to reduce swelling.
  • Stretch your calves before bed to prevent night cramps.
  • Schedule your anatomy scan (usually done between weeks 18 and 22).
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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 18

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Evidence-Based Clinical Sources for Week 18

PregWeeks is dedicated to medical transparency. Every milestone, symptom tip, and fetal development guideline for Week 18 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.