According to my calculations, I’m four weeks along today 🙂 I smile–but also get that tinge of nervousness, because 4 weeks is SO early. I’m praying every day for a healthy baby who sticks.
So if I’m right, and I am at four weeks, here are some of the things going on in my uterus right now! (According to the following apps: babycenter, What To Expect, and BabyBump.)
- My baby is less than a tenth of an inch big–still the size of a poppyseed! It* weighs less than four hundredths of an ounce!
- The blastocyst (in week three, the fertilized egg was called a zygote–now it’s graduated to blastocyst!) is now officially considered an embryo and is busy implanting into the lining of my uterus where the placenta will continue to develop.**
- The amniotic sac that will house my baby is forming, also called the bag of waters. So is the yolk sac, which will later be incorporated into my baby’s digestive tract.
- The embryo will now have three distinct layers of cells that will grow into 1) endoderm, the inner layer, the baby’s digestive system, liver, and lungs; 2) the middle layer, mesoderm, the baby’s heart, sex organs, bones, kidneys, and muscling; 3) the outer layer, ectoderm, will form my baby’s organs and tissues, including the nervous system, hair, skin, and eyes.
- The rudimentary versions of the placenta and umbilical cord are already functioning!