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What changes occur in a fetus during the fourth month after conception?
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pregnancy
Devices for individual use at home detect pregnancy by measuring levels of the hormone human chorionic gonadotropin (hCG) in urine.
During the fourth month of prenatal development, the fetus undergoes several notable changes as it continues to grow and mature:
- Facial Development: Individual differences between the faces of fetuses become distinguishable. While the face remains broad, the eyes become less widely separated than in previous stages.1
- Umbilical Attachment: The umbilical cord shifts its attachment point to a higher position on the abdominal wall. This change occurs due to the development of an expanding region between the cord and the pubis (the front bones of the pelvis), an area that was previously underdeveloped.1
- Growth: By the end of the fourth month, the fetus reaches an average crown-rump length of approximately 135 mm (5.3 inches) and weighs about 170 grams (6 ounces).1
These developments are part of the fetal period, which is characterized by dramatic growth and the gradual refinement of physical structures.2