Obstetricians calculate pregnancy duration from the first day of the last menstruation. Сonception occurs in the middle of the menstrual cycle, so the 3rd week of pregnancy is the first week of your child’s life.
Signs of pregnancy in the 3rd week
During this period, hardly any signs of pregnancy can be observed. Women often feel slight dizziness, drowsiness, drawing pain in the lower abdomen and slight swelling of the breasts. Read more about the first signs of pregnancy.
The fetus in the third week of pregnancy
During the third obstetric week, the baby is just a group of cells. Your zygote is still in the fallopian tube. It is actively moving towards the uterus to attach to its wall. If this process is successful and the zygote falls into the uterine cavity, implantation happens. Now the embryo will be in the inner shell and will start to attach to the uterine wall. On the 20−21st day of life, an embryo must tightly attach to this supportive and nourishing environment.
This attachment process may be accompanied by drawing pain in the abdomen and slight bleeding. During the implantation process, which lasts for about 40 hours, the outer cells divide and penetrate into the mucous membrane of the uterus, where they begin to grow and divide even more rapidly. The outer cells will soon form blood vessels that will eventually form placenta. Placenta will give strength to the growing fetus until the birth. Your baby will be formed from embryonic knot.
In the 3rd week of pregnancy, a fetus establishes strong ties with the mother. Now the embryo will get absolutely everything from the mother’s body. Your placenta is completely wonderful. It is a real source of life. The main function of the placenta is to transfer blood, rich in oxygen, from a mother to a child through the umbilical vein of a fetus. At the same time, it takes different toxins away from the arteries. Placenta performs the functions of lungs, digestive system and kidneys for your fetus. Moreover, it is a filter, which creates a barrier between harmful substances, viruses and bacteria from the external environment and your baby. In addition, the placenta produces hormones and various biologically active elements that play an important role in the process of development of the fetus in the womb.
In the third week of pregnancy, your baby looks like a ball with a diameter of 0.1−0.2 mm. The fetus is in a tiny water bag filled with amniotic fluid. The embryo’s nutrition happens by means of protein absorption. The glands of the uterine tubes secrete the protein for the baby.
You can have an ultrasound at this time to diagnose your pregnancy. This is how your baby looks in the third week of pregnancy.
After implantation, a woman’s body begins to receive first signals of a new life. Since the implantation of a fertilized egg, the level of human chorionic gonadotropin (hCG) begins to grow. The majority of modern pregnancy tests are based on the indication of hCG levels. The normal hCG level in humans is 2−5, but starting with the first day after implantation, the level of hCG begins to double every day. On the third week of pregnancy, a pregnancy test may show you two strips.
HCG is a catalyst for the development of cells, which produce the hormone progesterone. This hormone is essential in the first trimester of pregnancy. Progesterone is responsible for the relaxed state of the uterus. It is important because the muscular movements of the uterus complicate the attachment of the egg. Sometimes progesterone levels are low. In such cases, doctors prescribe progesterone drugs. This hormone makes a pregnant woman sleepy.
The third week of pregnancy is the time when you should be extremely attentive to your own health, especially if the pregnancy is planned and long awaited. After ovulation, refrain yourself from all sorts of physical activities and traveling, do not work hard and keep calm. Avoid any stressful situations. These are your baby’s first days, so be very careful and calm. Let your fetus safely reach his new dwelling in your uterus.
Avoid taking potent drugs, especially antibiotics. At this stage, internal organs of the fetus are formed, so it is important to protect your baby from any negative influences. Alcohol, physical overload, x-ray, active sex and unhealthy diet can fatally affect your child.