With the growth of uterus its weight blocks the drainage of urine
from the bladder, causing an infection
. An untreated UTI can cause kidney infection
. Kidney infections can lead to early labor and low birth weight. A urinalysis and urine culture will help in detecting if there is UTI.It can be easily treated with antibiotics which are safe during pregnancy. Seek the appointment of a doctor at the earliest. Keep me posted.
Best luck and take care!