Hello. I can understand your concern. Metrogyl is relatively safe in pregnancy and belongs to category B which means no adverse effects to the fetus have been shown in animal studies. Also, any adverse effects to the fetus due to medicines generally occur if taken in the first trimester. However, I would suggest you take any antibiotic only if fully indicated i.e. you do have a known infection. I assume your doctor has prescribed it based on clinical suspicion of an infection. Hence you can take it for the prescribed period. I would like to suggest you take probiotics like sporolac or enterogermina capsules three times a day. These are relatively safe and with lesser side effects. Curd or yogurt also helps. Also, avoid eating outside food or spicy and oily food. The issue should resolve in 1 to 2 weeks. Also, it wont affect your blood sugars, and you may continue your medications for gestational diabetes. Hope this helps. Wishing you a happy pregnancy. Regards, Dr Geeta