The phenomenon of not swollen breasts suddenly appears in 5 weeks of pregnancy, do not be too nervous, it does not explain the problem, after the appearance of this symptom, first of all, you should promptly go to the hospital for ultrasound examination, to see the development of the pregnancy capsule. If the gestational sac is well developed and there is no feeling of chest distension, it is also a normal performance, which is related to endocrine secretion. However, if the ultrasound shows that the gestational sac is not well developed, or there is shrinkage of the gestational sac, it means that the breasts suddenly do not swell due to fetal abortion, resulting in the sudden cessation of the pregnancy response, and there is no need to keep the baby in this situation. In this case, there is no need to keep the pregnancy. You should do the uterus removal in time to avoid the residual of the pregnancy sac in the uterine cavity for too long, which will cause the infection in the uterine cavity, and in this case, you can do the manual uterus removal surgery or use the medicine to promote the contraction of the uterus to facilitate the expulsion of the pregnancy sac.