Final answer:
The nurse's suspicion of a UTI is based on the client's symptoms of increased frequency of urination and foul-smelling vaginal discharge.
Step-by-step explanation:
The nurse based her suspicion of a urinary tract infection (UTI) on the client's symptoms of increased frequency of urination and foul-smelling vaginal discharge. These symptoms are commonly associated with UTIs, as the infection can cause irritation and inflammation of the urinary tract and vaginal area.
While the client's leg and ankle edema and positive Chadwick sign are not specific signs of UTIs, they may be indicative of other conditions or complications related to pregnancy.