The tenth week of pregnancy marks the end of the embryonic stage and the beginning of the fetal stage. At this point, the fetus is approximately 3.5 cm long and weighs about 4 grams.
Here are some key developments that occur during the tenth week of pregnancy:
Rapid growth: During this week, the fetus undergoes a period of rapid growth. Its body begins to elongate, and its head becomes more proportional to the rest of its body.
Fully formed organs: By the end of the tenth week, the fetus’s major organs, such as the heart, liver, and kidneys, are fully formed and are beginning to function. The fetus also starts to produce its own blood cells, which will replace the cells produced by the yolk sac.
Facial features: The fetus’s facial features continue to develop. Its eyes move closer together, and its ears move to their final positions on the sides of the head. The eyelids fuse shut to protect the developing eyes until they are ready to open later in the pregnancy.
Limb development: The fetus’s arms and legs continue to develop, and the fingers and toes become more defined. The bones in the arms and legs begin to harden, and the fetus can move its limbs more freely.
Reproductive organs: The fetus’s sex organs continue to develop during the tenth week, but it is still too early to determine the sex of the fetus through an ultrasound.
Movements: The fetus is becoming more active, and may even begin to make small movements such as kicking or flexing its fingers.
Overall, the tenth week is a critical time for the fetus as it transitions from the embryonic to the fetal stage. While the fetus is still quite small, it is rapidly developing and beginning to resemble a fully-formed baby.
