Dirty underwear 4.5 days before menstruation is not necessarily pregnant, may be normal leukorrhea, may be caused by a small amount of luteal insufficiency bleeding, may also be caused by a variety of inflammation caused by abnormal leukorrhea.
4.5 days before menstruation, there will be normal secretion of leukorrhea, if you do not pay attention to hygiene, there will be dirty underwear; luteal insufficiency a small amount of bleeding is mostly reddish-brown secretion, there will also be dirty underwear; if there is inflammation, the leukorrhea will also be abnormal, resulting in dirty underwear.
Pregnancy is mainly determined by blood and urine HCG (human chorionic gonadotropin) and ultrasound of the uterine adnexa, and it is not possible to determine whether or not you are pregnant simply by having dirty underwear. However, if you are pregnant, due to changes in estrogen and progesterone levels, there will be an increase in vaginal discharge, but usually not accompanied by abnormal color of the leukorrhea, itching and discomfort, etc. Increased discharge can also lead to very dirty underwear.
If you suspect that you are pregnant, you should go to the hospital in time for a professional physician to make a judgment.