Week 27 Size: Lettuce
About the size of a head of romaine lettuce.
Relative Visual Scale
Solid circle represents your baby's size. Dotted circle shows the full-term week 40 size threshold.
Baby's Development
This is the final week of the second trimester. The baby's lungs, liver, and immune system are maturing, though they still need a few more weeks to develop fully. Fetal brain tissue is growing rapidly.
Weekly Milestones
- ✦ End of Trimester 2
- ✦ Immune System Prep
Your Body & Symptoms
You are reaching the end of the second trimester! You might experience leg cramps, backaches, and pelvic pressure as the baby's weight presses on your lower body.
Common Symptoms this Week
Doctor & Care Recommendations
- ✓ Maintain a steady intake of iron and vitamin C.
- ✓ Avoid heavy lifting and take frequent sitting breaks.
- ✓ Sign up for a pediatric clinic tour or interview.
PregWeeks
CHECKLISTUltimate Hospital Bag & Birth Plan
Print-Ready PDFThe Ultimate Hospital Bag Checklist & Birth Plan PDF
Prepare for labor with confidence. Our doctor-reviewed checklists ensure you don't forget any newborn or partner essentials in the hospital delivery room.
- ✓ Clinical OB-GYN Approved List: Separate checklists detailing exactly what mom, partner, and newborn baby require for a standard 3-day recovery stay.
- ✓ 10-Second Birth Preference Builder: Minimalist visual plan templates designed to help delivery nurses digest your labor choices instantly on check-in.
- ✓ 1-Click Offline Access: High-resolution, print-ready document formatted to download directly to your mobile device for offline reference in the clinic.
Weekly Health Guides & Resources
Second Trimester Guide
Read comprehensive clinical milestones, screening checklists, and developmental guidelines for this phase.
Track & Relieve Symptoms
Learn why symptoms occur, home remedies, and clinical indicators for this week:
Food Safety Checklists
Verify safety statuses, listeria and mercury risks, and safe alternatives for:
Frequently Asked Questions: Week 27
Evidence-Based Clinical Sources for Week 27
PregWeeks is dedicated to medical transparency. Every milestone, symptom tip, and fetal development guideline for Week 27 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)
ACOGClinical 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)
ACOGPractice 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)
ACOGStandardized protocols for glucose screening tests to detect gestational diabetes and optimize maternal-fetal metabolic health.
View Clinical Guideline ↗Get weekly pregnancy updates
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