According to Oxford Dictionaries, when speaking of human development, the term embryo refers to the first eight weeks of pregnancy, while fetus refers to the later stages of pregnancy after eight weeks. The first stages of pregnancy are referred to as the zygote, which is followed by the cells developing into an embryo.Continue Reading
According to MedlinePlus, cells within the embryonic stage begin to multiply and take on specific functions. These functions include creating blood and nerve cells. This process is important, as these different cells and their functions make up what will eventually become a human being with a heart, brain and organs. During the eighth week of pregnancy, the heart beats with a regular pattern, reports the Office on Women’s Health. Embryonic cell growth is fast during this stage of pregnancy resulting in external forms taking shape.
The term fetus refers to the stages of a pregnancy after eight weeks when the cells have formed enough to look more like a miniature human being. The fetus has arms and legs by the ninth week of pregnancy, and the brain and lungs begin to form at this point, according to MedlinePlus. By the 10th week of pregnancy, the fetus has eyelids, ears and other facial features. After the 10th week, the fetal period begins, marking the beginning of the gestational age of a human pregnancy.Learn more about Pregnancy
A missed miscarriage occurs when an embryo or fetus dies without being expelled from the expectant mother's body, and, thus, the mother is unaware that her pregnancy has terminated itself, explains Women's Health. Missed miscarriages may require medical intervention to remove the tissues associated with pregnancy to prevent infection.Full Answer >
According to WebMD, the symptoms of pregnancy at four weeks are a missed period and possible light spotting as implantation of the embryo occurs in the uterus. When a woman is four weeks pregnant, the egg containing the fetus has only recently been fertilized. This means that some women may not notice any symptoms of pregnancy at four weeks.Full Answer >
The belly at 14 weeks pregnant varies in size depending on the woman, but the fetus is approximately the size of a lemon, according to The Bump. The fetus is roughly 3.4 inches long and weighs about 1.5 ounces.Full Answer >
At 36 weeks, a fetus nears full growth and takes up more space in the womb, so the mother may have a smaller appetite, BabyCenter notes. As the baby moves toward the pelvic cavity, the mother experiences reduced heartburn and more intense pressure on the lower abdomen and vagina. Depending on the woman, this dropping process may occur at a later week. Other symptoms include frequent urination and difficulty walking, and the rate of Braxton Hicks contractions may increase.Full Answer >