Recurrent uti. It effect foetus growth.

My wife is 25 week pregnant.... We consulted a urologist for recurrent uti (second time in pregnancy).. 1st time her gyne gave her martifur bd for seven days.... After that urine r/m came negative and were advised to stop med... Again in routine check urine r/m.... Infection was diagnosed (as such there were no symptoms) we consulted a urologist... He advised monocef 2mg iv 7 days bd... After that test urine r/m showed negative result no infection.. But still he advised for taking ceftum 500mg bd for 7 days.. Again urine r/m done... Urine r/m result negative no infection.. Now again doctor has adviced ceftum 250 mg one tablet in night for 2 weeks... Now i am very much concerned is it safe to have so much of antibiotics during 25 month pregnancy... Need urgent advice...will it effect foetus growth.. Our gyne is out of india..