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Pregnancy - first trimester
Medical expert of the article
Last reviewed: 06.07.2025
[ Early fetal development
Within a week of fertilization, the fertilized egg develops into an embryonic sac that attaches to the wall of the uterus. This implantation triggers a series of hormonal and physical changes in the woman's body. The period from the third to the eighth week of the embryo's development is called the embryonic stage, during which the embryo develops its most important vital organs. During this period, it 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 is the size of a grapefruit.
Early signs of pregnancy
The first sign of pregnancy is the absence of a menstrual cycle. Hormonal changes also provoke other signs:
- Fatigue
- Breast pain
- Frequent urination
- A feeling of mild pain or fullness in the abdomen
- Nausea, with or without vomiting - morning sickness
Other changes associated with pregnancy
During pregnancy, a number of other symptoms may be observed, the nature of which varies from mild to severe.
- Constipation caused by hormonal changes that slow down the normal functioning of the intestines. In addition, the presence of iron in vitamins can also cause constipation.
- Mood changes due to hormonal changes, excessive fatigue or stress due to expecting a baby.
- Changes in vaginal discharge. Watery milky discharge is considered normal during pregnancy. Also, the skin around the vagina becomes thicker and less sensitive.
- Vaginal yeast infections are common due to elevated hormonal levels. Consult your doctor at the first sign of a vaginal yeast infection.
- Vaginal bleeding: Light bleeding in early pregnancy may go away on its own, but it may also be a sign of an impending miscarriage.
Consult your doctor immediately at the first sign of vaginal bleeding.