Is it normal for twins to be one big and one small?

Twins are very common in life. They are usually formed by two fertilized eggs. Many pregnant women with twins are prone to one being bigger than the other during pregnancy. It is relatively normal for twins to be one bigger than the other. This is caused by the different absorption of nutrients by the gestational sac, or the different nutrients absorbed by the twins. Pregnant women can adjust their diet and nutritional intake reasonably.

Is it normal for twins to be one big and one small?

It is normal for twins to have one bigger than the other. It is impossible for two babies to have exactly the same weight. As long as they are not too thin, it is generally not a problem.

What is the reason for the gestational sac to be one large and one small?

It depends on the size difference. If one is particularly big and the other is particularly small, and they are not developing well, it may be bad. Detecting two gestational sacs can confirm that it is twins. It's normal to have a little difference in size.

If there are two gestational sacs, it generally means that you may be having twins, but if you still don't see the embryo or fetal heartbeat, you still need to wait and see.

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. For women whose menstruation is regular every 28 to 30 days, after 35 days of amenorrhea, the gestational sac can be seen in the uterine cavity by B-ultrasound.

Observation of gestational sac

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. 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. In the second week, the embryo implants in the endometrium. When it develops into the second germ layer, a large cavity called the primary yolk sac appears on the ventral side of the embryonic disc. The yolk sac continues to shrink and degenerate during embryonic development, but the extraembryonic mesoderm on the wall of the yolk sac is the earliest origin of the formation of blood cells, blood vessels and primitive germ cells - the gestational sac, where the fetus will grow in the future.

The gestational sac is only seen in early pregnancy. For women whose menstruation is regular every 28 to 30 days, after 35 days of amenorrhea, the gestational sac can be seen in the uterine cavity by B-ultrasound. 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.