If the gestational sac is irregular, fetal arrest may occur. Gestational sac only appears in the early pregnancy. Its size is about 2 cm in diameter at 1.5 months of pregnancy, and it is normal at 2.5 months. The position of gestational sac is normal in the bottom, front wall, back wall, upper part and middle part of uterus. Normal shape is round, oval and clear; If the gestational sac is irregular, fuzzy and located in the lower part, the pregnant woman may miscarry at the same time as abdominal pain or vaginal bleeding.
Gestational sac is the primitive placental tissue, which is a small embryo wrapped by amniotic membrane and vascular network. Gestational sac is the initial form of pregnancy. At that time, before the fetus was formed, the fetal heart beat when the embryo bud appeared. Gestational sac only appears in the early pregnancy. For women with menstrual cramps for 28-30 days, after 35 days of menopause, the gestational sac in the uterine cavity can be seen by B-ultrasound. Gestational sac is also the product of ectopic pregnancy. Due to inflammation and adhesion, the fertilized egg did not enter the uterus on the 7th day. Usually ectopic pregnancy will bleed heavily, and generally speaking, the fetus can't survive. If the pregnant woman is pregnant in utero, but gestational sac breaks from the weak top of the uterus and enters the abdominal cavity, the villi around gestational sac look for nutrients everywhere in the abdominal cavity, and then supply them to the fetus through the placenta. Usually, such a fetus is not protected by the uterine environment, the living environment is extremely bad, and the nutrition is relatively poor. The fetus will die within two months.
The gestational sac-sized fetus at 40 days of pregnancy grew to 0.85 cm at 40 days of pregnancy. Differentiation of fetal head, brain vesicles, frontal organs, respiratory organs, digestive organs, nerves and other organs. B-ultrasound can clearly see the fetal sac, and can see the embryo and fetal heartbeat.
Gestational sac is too young, because emotional stress leads to delayed menstruation, wrong ovulation period and late pregnancy, so gestational sac is shorter than the actual menopause days. For example, menopause lasts for 50 days, but the gestational sac size is only about 40 days. It is normal that the gestational sac is too small. After a week's dynamic examination, the values of chorionic gonadotropin and progesterone are gradually increasing, the gestational sac continues to grow, and the embryo and fetal heart gradually appear, indicating that due to physiological reasons such as wrong ovulation date and late pregnancy time, the gestational sac is too small and pregnancy can continue.
Secondly, due to the poor development of sperm and eggs, pregnant women are infected with mycoplasma, chlamydia and rubella virus during pregnancy, or pregnant women are exposed to toxic and harmful substances during pregnancy, resulting in poor development of gestational sac, which is less than normal months. During pregnancy, as time goes by, the gestational sac will continue to grow, but the embryo and fetal heart can't be seen. In this case, the gestational sac is unhealthy and will eventually lead to miscarriage.
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