CAN ANTIBIOTICS INCREASE THE RISK OF PRETERM BIRTH? It has been well established that inflammation in the vaginal vault during a pregnancy can increase the risk of a preterm birth. One of the factors that can contribute to inflammation is bacterial vaginosis (dysruption of the normal bacterial flora), which can be brought about by destruction of the normal vaginal flora with antibiotics.
So the answer is yes–antibiotics taken by a woman before or during pregnancy can increase the risk of preterm birth, as well as leave the as-yet-unborn infant without the right bacteria to jump start their immune system. The good thing is that the answer can be as simple as replacing normal flora via oral supplementation or via douching. Or just avoiding antibiotics in the first place (unless absolutely necessary).