Your baby is transforming from a ball of cells to something that looks slightly more human this week. The embryo is currently made up of three layers of cells: the ectoderm, mesoderm and endoderm. The ectoderm will become your baby’s brain, spinal cord, skin and nails. The mesoderm will become the heart and circulatory system, and the endoderm will become the lungs, intestines and other major organs.
Baby's brain and spine are some of the first things to develop; the brain and spine together are known as the "neural tube". The neural tube needs folic acid to develop properly, which is why prenatal vitamins are recommended for every pregnant person. (You probablyyy get enough folic acid from your diet, but just to make absolutely sure, your doctor will tell you to take prenatals, since neural tube defects can be pretty serious, and it's so easy to 100% avoid them just by supplementing folic acid.)
The hormone hCG (human chorionic gonadotropin), or the "pregnancy" hormone, is now at a high enough level in your system to be detected by a home pregnancy test. If you usually have a regular menstrual cycle, this is also the week where you'll miss your period. Pregnancy tests work the most reliably starting the day after you expect your period, but some of them are still fairly accurate a few days before.
Some people's pregnancy symptoms get going really quickly and aggressively, while other people don't feel anything at all. At this point, there's no use stressing over whether or not you're having symptoms!
Lower Abdominal Pressure - some people report pressure or cramping when the fertilized egg implants, and in the weeks following.
Metallic Taste - hormones can cause a metallic taste in your mouth, or cause foods to taste differently. This may be something you're used to from PMS, or it might be an unfortunate new experience. Some people recommend drinking or eating acidic things if it gets unbearable.
Implantation Bleeding - fewer than 25% of people report a slight amount of bleeding during implantation. If you don't know you're pregnant, this can be mistaken for your period. If you're hoping you're pregnant, this can be scary and sad since it occurs when you'd expect your period. If you're in the latter camp, you can refer to our miscarriage page for advice and reassurance.
Tender Breasts - pregnancy hormones signal your breasts to start getting ready to produce milk. Since your body will need to build up the infrastructure to breastfeed, your breasts will undergo some pretty serious changes over the length of your pregnancy. One of the first pregnancy symptoms many people report is tenderness in their breasts.
Stronger Sense of Smell - another common early-pregnancy symptom is a more sensitive nose. Things might smell much stronger than normal, or even differently than they normally do. This is another symptom you may be familiar with from PMS, or it might be something new to you. Fishmother used this symptom to her advantage to make sure she never ate anything even slightly old or spoiled, since she could smell immediately when things were bad.