Fetal development in pregnancy week 4:embryo in first month
By the end of this week the round and pointy ends of your little pear-shaped baby will be slightly more exaggerated and their body will look more like that of a miniature manatee. Despite your baby not looking particularly human without any eyes, ears or mouth, the earliest developments of what will become the larynx, internal ear, and eye lens are already forming, although you’d have to be a trained expert to recognize them for what they’re going to be in the future. Likewise, tiny bumps are forming on your little embryo which will eventually be their cute little arms, elbows, fingers, legs, knees and toes. What’s more your little swimmer will have a teeny tiny tail by the end of this week-- but don’t worry, it’s just the end of their developing spinal cord! A microscopic photo would reveal what seems to be their vertebrae filling out the spine and tail. Although they aren’t bones yet, but rather, the “bone seeds” that will give rise to your baby's tiny vertebrae, ribs and sternum.
And how's mom doing?
This week is not unlike the previous weeks; your pregnancy symptoms may be increasing, as expected. In fact, the earliest symptoms of morning sickness may set in for some women at this time. The not-so-lovely symptoms run the normal flu gamut including: nausea and vomiting. Although this typically the whole reason for morning sickness: to clear your system of any toxic food by-products which—although fine for your adult stomach, could cause considerable harm to your baby’s newly forming digestive tract and other body systems occurs in the morning and resolves itself by midday, morning sickness can come at any time, day or night, so—for some of you, you’ll just have to make frequent stops throughout the day to kneel before the porcelain throne. In general, most pregnant women don’t experience morning sickness until their sixth week, but it never hurts to know what vomit-y fate may be awaiting you.
Morning sickness is due to several changes that are taking place in your body. First, you are now pumping out significantly larger amounts of estrogen and progesterone than normal, and your body is not used to this. Interactions between the hormones and your stomach result in the less-than-wonderful nausea. Also, your GI-tract is much more sensitive and some doctors theorize that this sensitivity is potentially the whole reason for morning sickness: to clear your system of any toxic food by-products which—although fine for your adult stomach, could cause considerable harm to your baby’s newly forming digestive tract and other body systems . If it helps, you could always think of the morning sickness as a baby-facilitated body cleanse.