Following antibiotics are safe to pregnancy:

Penicillin and its derivatives has a wide margin of safety and are not toxicto mother or fetus streptomycin:cause ototoxicity Tetracyclines including doxycline can cause staining of teeth and potentially skeletal abnormalities Quinolones like ciprofloxacin and norfloxacin are best avoided as they are toxic to developing cailage first trimester cotrimoxazole has been associated with bih defects especially cardiovascular TEXTBOOK OF OBSTETRICS, SHEILA BALAKRISHNAN,Pg no:569,2nd edition