Pregnancy Home > Pregnancy > Pregnancy Week By Week
Pregnancy Week by Week: Your Guide to Your Baby's Development
Although many people focus on the trimesters, there is something new going on in your pregnancy week by week. Here's a guide to your baby's development.
Weeks 1 and 2: This is actually pre-conception. You ovulate and then sometime during these 14 days, you'll become pregnant.
Weeks 3 and 4: The fertilized egg moves down the fallopian tubes and implants into the uterine wall. At this point, your future baby is called an embryo. The placenta starts to form and you'll begin to feel pregnant, even if you don't know it yet.
Weeks 5 and 6: Your baby's spinal cord and brain begin to form and at the end of this period, the heart begins to beat.
Weeks 7 and 8: This marks the start of rapid growth. Your baby doubles in size, and tiny details like the tongue, eyes, teeth buds, voice box and arm buds begin to form. It's amazing how quickly they develop all of the essential organs.
Weeks 9 and 10: Your embryo is officially a baby! He or she has all of the necessary parts, albeit on a smaller scale. Your baby starts to develop cartilage and bones. The arm buds begin to show definition and fingers form, and the toes form as well. At this point, your baby will become more active.
Weeks 11 and 12: By this point, your morning sickness should subside. The brain has reached the structure that it will have when the baby is born.
Weeks 13 and 14: The vocal chords form, and the intestines move into the abdomen. Your baby's heartbeat can be detected with a Doppler. He or she begins to practice movements like breathing, sucking and swallowing.
Weeks 15 and 16: Your baby is practicing using his or her new muscles. The baby will kick, open their mouth and press their feet together. Toward the end of this period, your uterus will start moving up, meaning you'll show more.
Weeks 17 and 18: Your baby's face begins to take shape as the eyes and ears move to their right places. The digestive system will form meconium, a dark black substance that will fill the bowels. The nervous system also develops during this period.
Weeks 19 and 20: By the end of this period, your baby will have increased 6 times. Vernix, a white, creamy substance, starts to cover the baby's skin. Your baby will have periods of sleeping and waking, just like they will outside the womb.
Weeks 21 and 22: The muscles tone and bones become stronger as your baby moves around your uterus. He or she will grow visible hair and eyebrows.
Weeks 23 and 24: Your baby can now hear, and begins a one-month period of major weight gain.
Weeks 25 and 26: Your baby's lungs develop, and the skin turns pink. He or she will practice breathing and brain wave activity starts.
Weeks 27 and 28: Your baby will open his or her eyes for the first time. You'll feel kicks consistently from here on out.
Weeks 29 and 30: If your baby were born now, there is a good chance he or she would survive. The baby begins storing nutrients from your body like calcium, protein and iron.
Weeks 31 and 32: Growth slows down at this point, but the internal organs continue to develop. All five senses are working now.
Weeks 33 and 34: Your baby's immune system develops and the eyes begin to react to light.
Weeks 35 and 36: At this point, your baby will likely be in birth position with his or her head down into your pelvis. Fat deposits form as your baby readies for birth.
Weeks 37 and 38: Your baby is considered full term, and might even be born a few weeks before your due date.
Weeks 39 and 40: If you haven't given birth yet, your baby will continue to drop into your pelvis. You'll also produce antibodies to protect your baby from diseases.
Weeks 41 and 42: Many babies are born a week or two after their due date. You'll probably be feeling clumsy and uncomfortable at this point, as your center of gravity shifts with the weight of the baby.
"Foods To Avoid During Pregnancy"
... and receive our free ezine filled with healthy pregnancy tips!