Follow the fetal development here week by week, from fertilization until the moment when a woman actually knows she is pregnant. Check out my posts that always cover two weeks of pregnancy at a time, all the way until the baby is born. 
1st Trimester
Weeks 1 to 4: It all begins right here, even before you can imagine the start of a new journey. A new life arises from just two cells. You might not even know it yet, but you’re about to discover the greatest love in the world! From now on, follow your baby’s fetal development. Weeks 5th to 6th: If you have an ultrasound at this stage, you’ll probably already be able to see what is just the early beginning of your baby’s development. The heart starts to beat, and your baby’s fetal development is in full swing! Weeks 7th to 8th: Now your baby is starting to develop tiny fingers, and the spine is being formed. Fetal development is very fast and accelerated, bringing something new every day. Weeks 9th to 10th: Your baby’s sexual organs are forming, but it is still not possible to tell if it is a boy or a girl—the fetal development doesn’t stop! Weeks 11th to 12th: Now, the riskiest phase of pregnancy is over! The pregnancy has just entered the 2nd trimester and with it, morning sickness is going away, hooray! Fetal development is still very intense, with the stomach and kidneys forming and beginning to function.
2nd Trimester
Weeks 13th to 14th: From now on, your belly will start to show and the baby is already quite long, looking like a tiny human. If your doctor hasn’t yet requested the ultrasound for Nuchal Translucency, now is the perfect time. Fetal development now becomes a bit slower than during the initial phase. Weeks 15th to 16th: It’s time to find out the sex! At this stage, it’s visible and easier to distinguish boy or girl? Fetal development continues and the lanugo begins to appear. Weeks 17th to 18th: Now the mother may start to feel the baby’s movements. At first, it may feel like a bunch of little butterflies inside your belly. Your baby’s fetal development becomes more obvious, both in your belly and your weight, which starts to become more noticeable. Weeks 19th to 20th: Half of the pregnancy has already passed, and now your baby is very active, moving a lot, sucking on tiny fingers, and stretching out. At this stage, you can see fetal development through a morphological ultrasound. Weeks 21 and 22: Your baby can already hear mom and dad’s voices, and even recognize external sounds. Fingernails start to grow—another milestone of fetal development. Weeks 23 and 24: It’s time to start shopping for the layette, and now your baby could already breathe on their own if born. Weighing about 600 grams, the baby sucks their hand and plays with their feet—two more stages of fetal development. Weeks 25 and 26: Now the movements are already quite strong and even dad can feel them! Weeks 27 and 28: All of mom’s organs are working at full speed, the heart and lungs have to supply two bodies with oxygen.
3rd Trimester
Weeks 29 and 30: With weight and measurements that can surprise parents during the ultrasound, the baby’s movements are very strong and everyone can feel them! Weeks 31 and 32: Feeling tired is normal; your baby weighs about 2 kg! Now, all that’s left is to gain weight for birth. Weeks 33 and 34: The baby may turn at this stage, now moving into the cephalic position, head down, already preparing for delivery! Weeks 35 and 36: This is a phase when, even though the mom feels tired, she feels more than rewarded. Your baby moves vigorously and now the birth can already be planned together with the doctor. Weeks 37 and 38: With the approach of labor, the mother may feel more anxious, so relax and enjoy the last moments of pregnancy! Weeks 39 and 40: Finally, childbirth! Are you ready for the greatest emotion and the greatest love of your life?
