First Trimester (Weeks 1-12)
The first trimester is a time of rapid development. Your baby goes from a single cell to a fully formed fetus with all major organs. Many women experience morning sickness, fatigue, and emotional changes during these early weeks.
Week 1 — Ovulation & Conception
Week 2 — Fertilization Week
Week 3 — Implantation Begins
Week 4 — Pregnancy Confirmed
Week 5 — Heart Begins Forming
Week 6 — Heartbeat Detectable
Week 7 — Rapid Brain Growth
Week 8 — Size of a Raspberry
Week 9 — Organs Forming
Week 10 — Officially a Fetus
Week 11 — Fingers & Toes
Week 12 — First Trimester Ends
Second Trimester (Weeks 13-27)
The second trimester is often called the “golden period” of pregnancy. Morning sickness typically fades, energy returns, and you’ll start feeling your baby move. This is also when you’ll have your anatomy scan and may learn your baby’s sex.
Week 13 — Second Trimester Starts
Week 14 — Facial Expressions
Week 15 — Sensing Light
Week 16 — First Flutters
Week 17 — Skeleton Hardening
Week 18 — Baby Can Hear
Week 19 — Vernix Forming
Week 20 — Halfway Point
Week 21 — Taste Development
Week 22 — Senses Developing
Week 23 — Viability Milestone
Week 24 — Viability Reached
Week 25 — Hands Developed
Week 26 — Eyes Opening
Week 27 — Third Trimester Begins
Third Trimester (Weeks 28-40)
The final stretch. Your baby is gaining weight rapidly, practicing breathing, and preparing for birth. You’ll experience more physical discomfort but also growing excitement as your due date approaches.
Week 28 — Blinking & Dreaming
Week 29 — Bones Developed
Week 30 — Brain Development
Week 31 — Sleep Cycles
Week 32 — Practicing Breathing
Week 33 — Immune System
Week 34 — Lungs Maturing
Week 35 — Rapid Weight Gain
Week 36 — Nearly Full Term
Week 37 — Full Term!
Week 38 — Labor Could Start
Week 39 — Final Countdown
Week 40 — Due Date
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