How to distinguish gestational sac and decidua

It is well known that for women of childbearing age or young couples who are preparing to have children, knowing some things about pregnancy and childbirth in advance will be of great benefit to future child-rearing. When looking through relevant books, words such as gestational sac and decidua often appear. The former is a small embryo, generally wrapped in a vascular network and amniotic membrane, while the latter is the key to establishing and maintaining the embryo. So how do we distinguish between the two clinically?

Gestational sac

The gestational sac is the primitive placental tissue, a small embryo wrapped by the amniotic membrane and vascular network. The gestational sac is the initial form of pregnancy. At that time, the fetus has not yet formed, and the fetal heartbeat is already there when the embryonic bud appears.

The gestational sac is also a product of ectopic pregnancy. The fertilized egg fails to enter the uterus at 7 days due to certain factors such as inflammation and adhesion. Ectopic pregnancy usually causes heavy bleeding, and generally the fetus cannot survive. The mother of the little baby was experiencing an intrauterine pregnancy, but due to poor development of the uterus, the gestational sac broke through the weak top of the uterus and entered the abdominal cavity. The villi around the gestational sac sought nutrients everywhere in the abdominal cavity and then supplied them to the fetus through the placenta. Usually, such a fetus will die within two months because it has no protection from the uterine environment and lives in an extremely harsh environment with poor nutrition.

The gestational sac is only seen in early pregnancy. Menstrual period 28 to 30 days rule

For women who are menstruating, the gestational sac can be seen in the uterine cavity by B-ultrasound 35 days after the menstruation. The diameter of the gestational sac is about 2 cm at 6 weeks of pregnancy and about 5 cm at 10 weeks of pregnancy. It is normal for the gestational sac to be located at the fundus, front wall, back wall, upper part, or middle part of the uterus; it is normal for it to be round, oval, and clear in shape; if the gestational sac is irregular in shape, blurred, and located in the lower part, and the pregnant woman also has abdominal pain or vaginal bleeding, she may have a miscarriage.

Decidual tissue

The normal expression of endometrial decidua and decidual function plays an extremely important role in embryo implantation, pregnancy establishment and maintenance, and the initiation of labor. Studying the growth, degeneration and regulation of decidua is of great significance for clarifying the mechanism of embryo implantation and fertility regulation. With the continuous deepening of research on cell apoptosis and its regulatory mechanism, humans have paid more and more attention to the proliferation and apoptosis of decidual cells and their regulatory factors during reproduction, and have made corresponding progress.