Pregnancy week by week
Pregnancy calendar from week 1 to 40: baby development, how mom may feel, and practical tips.
All trimesters
Pregnancy by trimester
Weeks 1–13
First Trimester: Laying the Foundations of Life
The first 13 weeks of pregnancy are the time when all organs and systems of your baby are formed. You may experience the early pregnancy symptoms and adapt to new sensations.
Weeks 14–27
Second Trimester: The Golden Period of Pregnancy
Weeks 14-27 of pregnancy are often called the "golden period". Energy returns, the belly starts to grow, and you can feel the baby's first movements.
Weeks 28–40
Third Trimester: The Final Stretch to the Meeting
Weeks 28-40 of pregnancy are a time of active preparation for birth. Your baby is almost ready to enter the world, and you are preparing for the most important event of your life.
First Trimester: Laying the Foundations of Life
Weeks 1–13
Week 1: The Beginning of the Journey
The first week of pregnancy is the time of conception. Your baby does not exist yet, but your body is preparing for this event.
Week 2: Anticipating Ovulation
Week two is the time of ovulation and possible conception. Your body is ready for fertilization.
Week 3: Conception and Implantation
The third week is the time of conception and the beginning of a new life forming. Your baby begins its development.
Week 4: Implantation and the start of pregnancy
The fourth week is the time of embryo implantation into the uterus and the beginning of placenta formation.
Week 5: Beginning of Organ Formation
The fifth week is a time of active development. The formation of the heart, brain, and other organs begins.
Week 6: The Heart Starts Beating
Week six is an amazing moment when your baby's heart begins to beat!
Week 7: Development of the Face and Limbs
The seventh week is a time of active development of your baby's face and limbs.
Week 8: Transformation into a Fetus
The eighth week is the time when the embryo becomes a fetus. All major organs are formed.
Week 9: Limb Development
Week nine is a time of active development of the arms and legs. Your baby is starting to move!
Week 10: Completion of the Embryonic Period
Week ten marks the end of the embryonic period. Your baby is now fully formed.
Week 11: Development of Reflexes
Week eleven is a time of reflex development and active movements of your baby.
Week 12: End of the First Trimester
Week twelve marks the end of the first trimester. The risk of miscarriage drops significantly.
Week 13: Beginning of the Second Trimester
Week thirteen marks the start of the second trimester. The "golden period" of pregnancy begins!
Second Trimester: The Golden Period of Pregnancy
Weeks 14–27
Week 14: Development of the Sensory Organs
Week fourteen is a time of active development of your baby's sensory organs.
Week 15: Muscle Development
The fifteenth week is a time of active muscle development and strengthening movements.
Week 16: First Movements
Week sixteen is the time when you can feel your baby's first movements!
Week 17: Development of Fat Tissue
Week seventeen marks the beginning of fat tissue formation and skin development.
Week 18: Hearing Development
The eighteenth week is a time of active hearing development. Your baby is beginning to hear sounds!
Week 19: Brain Development
The nineteenth week is a time of active brain and nervous system development.
Week 20: Mid-pregnancy
The twentieth week is the middle of pregnancy! You have completed half the journey to meeting your baby.
Week 21: Lung Development
The twenty‑first week is a time of active lung development and respiratory system growth.
Week 22: Vision Development
The twenty‑second week is a time of active development of your baby's vision and eyes.
Week 23: Development of the Immune System
The twenty-third week is a time of active development of your baby's immune system.
Week 24: Brain Development
The twenty‑fourth week is a time of active brain development and cognitive functions.
Week 25: Lung Development
The twenty-fifth week is a time of active development of the lungs and respiratory system.
Week 26: Eye Development
The twenty‑sixth week is a time of active eye and vision development for your baby.
Week 27: End of the Second Trimester
The twenty-seventh week marks the end of the second trimester. Your baby is ready for the final stage.
Third Trimester: The Final Stretch to the Meeting
Weeks 28–40
Week 28: Beginning of the Third Trimester
The twenty‑eighth week marks the start of the third trimester. The final stage of pregnancy begins!
Week 29: Brain Development
The twenty-ninth week is a time of active brain and nervous system development.
Week 30: Lung Development
Week thirty is a time of active lung and respiratory system development.
Week 31: Development of the Immune System
The thirty-first week is a time of active development of your baby's immune system.
Week 32: Brain Development
The thirty‑second week is a time of active brain development and cognitive functions.
Week 33: Lung Development
The thirty-third week is a time of active development of the lungs and respiratory system.
Week 34: Development of the Immune System
The thirty-fourth week is a time of active development of your baby's immune system.
Week 35: Brain Development
The thirty-fifth week is a time of active brain and nervous system development.
Week 36: Preparing for Labor
The thirty-sixth week is a time of active preparation for labor. Your baby is almost ready!
Week 37: Full-term pregnancy
The thirty-seventh week is a full-term pregnancy! Your baby is considered full-term.
Week 38: Awaiting Labor
The thirty‑eighth week is a time of awaiting labor. Your baby could be born at any moment!
Week 39: Final Preparation
Week thirty‑nine is the final preparation for labor. Your baby is ready to meet you!
Week 40: Expected Due Date
Week forty is the expected due date! Your baby is ready to be born.