Pregnancy: first trimester

, medical expert
Last reviewed: 19.10.2021

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Pregnancy is measured trimester from the first day of the last menstrual cycle - only 40 weeks. The first trimester is 12 weeks or 3 months.

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Early development of the fetus

During the week after fertilization, the fertilized egg turns into a germinal vesicle, which is attached to the wall of the uterus. Such implantation provokes a number of hormonal and physical changes in the body of a woman. The period from the third to the eighth week of embryo development is called the embryonic stage, during which the embryo develops the most important vital organs. During this period, he is very sensitive to harmful substances, such as alcohol, radiation and infectious diseases. Having reached a length of 2.5 cm in the ninth week, the embryo is called a fetus. The uterus at this stage takes the size of the grapefruit.

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Early signs of pregnancy

The first sign of pregnancy is the absence of a menstrual cycle. Hormonal changes provoke other symptoms:

  • Fatigue
  • Chest soreness
  • Increased urination
  • Feeling of slight pain or fullness of the abdominal cavity
  • Nausea accompanied by vomiting or without it - morning toxicosis

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Other changes related to pregnancy

During pregnancy, you can observe a number of other symptoms, the nature of which varies from moderate to pronounced.

  • Constipation caused by hormonal changes that slow the normal functioning of the intestine. In addition, the presence of iron in the vitamins can also cause constipation.
  • Change in mood due to hormonal shift, excessive fatigue or stress due to expectation of the child.
  • Change in the nature of vaginal discharge. Watery milk allocation is considered the norm during pregnancy. Also, the skin around the vagina becomes thicker and less sensitive.
  • Vaginal fungal diseases are often associated with an elevated hormonal level. Consult with your doctor at the first sign of vaginal fungal disease.
  • Vaginal bleeding. A mild form of bleeding at an early stage of pregnancy can pass by itself, but this may be a sign of a beginning miscarriage.

Immediately consult with your doctor at the first sign of vaginal bleeding.

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