The gestational sac refers to the primitive placental tissue, a small embryo surrounded by the amniotic membrane and vascular network. Generally speaking, as the fetus grows, the size of the gestational sac also changes, and checking the size of the gestational sac is also necessary during pregnancy. Do pregnant women know what size the gestational sac is usually at 57 days of pregnancy? Follow the editor to take a look.
What is the typical size of the gestational sac at 57 days of pregnancy
The gestational sac is the initial form of pregnancy, when the fetus has not yet formed and the fetal heart is already beating when the embryo appears. At 57 days of pregnancy, the fetus grows to 1.66 centimeters and has a fixed fetal shape, which can be divided into a fetal head, body, and limbs. The fetal head is larger than the torso. Ultrasound shows that the fetal sac occupies about 1/2 of the uterine cavity, and the fetal morphology and movement are clearly visible, with the yolk sac visible.
Comparison table of gestational sac size
1. 4 weeks: The fetus is only 0.2 centimeters. The fertilized egg has just completed implantation and the amniotic cavity has just formed, which is very small in volume. Ultrasound still cannot detect signs of pregnancy.
2. 5 weeks: The fetus grows to 0.4 centimeters, enters the embryonic stage, the amniotic cavity expands, the primitive cardiovascular system appears, and there may be pulsation. B-ultrasound can show a small gestational sac, which occupies less than 1/4 of the uterine cavity, or a fetal bud can be seen.
3. 6 weeks: The fetus grows to 0.85 centimeters, and the fetal head, brain vesicles, frontal and facial organs, respiratory, digestive, nervous and other organs differentiate. The fetal sac is clearly visible on B-ultrasound, and fetal buds and heartbeat can be seen.
4. 7 weeks: The fetus grows to 1.33 centimeters, the embryo has taken on human embryonic form, all body segments have differentiated, limbs have separated, and various systems have further developed. B-ultrasound clearly shows the fetal bud and heartbeat, with the gestational sac occupying approximately one-third of the uterine cavity.
I believe that after reading this article, all pregnant women will have a clear understanding of the size of the gestational sac at 57 days of pregnancy. Interested pregnant women may want to take a look. If a small gestational sac is detected, it is necessary to seek medical attention promptly to avoid adverse conditions affecting fetal growth.
