Large sacs and small buds are usually associated with malnutrition, low progesterone levels and embryonic abruption. 1. Malnutrition: If you are chronically malnourished during pregnancy and have the habit of picking and favoring food, it will affect the absorption of nutrients by the embryo, thus causing the condition of large gestational sacs and small buds. 2. Low level of progesterone: If the level of progesterone is low during pregnancy, it can’t meet the developmental needs of the embryo, which may result in a large gestational sac and small buds. 3. Embryonic arrest: If the pregnancy sac is still large and small after a period of time, we should consider the reason that the embryo has stopped developing. In the clinic, if there is a large gestational sac and small buds, it is recommended to observe for a period of time, and then review again, and according to the diagnostic results of targeted treatment. If the embryo is found to have stopped developing, the embryonic tissue should be cleaned up as soon as possible.