The second day of the uterus no blood on the sixth day suddenly bleeding again may be normal, but also may be the uterine cavity residue, infection and other reasons, you can first observe, the use of medication, once again to clear the uterus, pay attention to life care. 1. Normal phenomenon: the second day of the uterus no blood on the sixth day suddenly bleeding again may be the uterine contraction has not completely returned to normal, due to increased activity, mental factors and other factors that stimulate uterine contraction caused by bleeding. This situation is not too nervous, no special treatment, relax your mind, pay attention to personal hygiene. 2. Uterine residue: the second day of purging no blood on the sixth day suddenly bleeding again may be the uterine residue, the uterine cavity has more residual tissue, not completely discharged will easily cause bleeding symptoms, you can use motherwort granules, biochemical pills to promote the discharge of blood, such as the uterine cavity tissue is more likely to need a second purging surgery. 3. Infection: the second day of the uterus, no blood on the sixth day of the sudden bleeding may be caused by infection, the uterus is not good after cleaning, disinfection, retrograde infection triggered by bleeding, you can take anti-inflammatory drugs such as oral amoxicillin, pay attention to rest, do a good job of personal hygiene. If you have a problem with the second day, you can go to the regular hospital in time and get treatment under the guidance of the doctor.