While the most common antibiotics were not linked to birth defects, the study shows that sulfa drugs and nitrofuranritoins were. Something to keep in mind during pregnancy. Here is an excerpt from the article and a link to the full report.
CDC Study Links Two Antibiotics to Birth Defects. No added risk was found, however, for most commonly used infection-fighters
However, the study found that two types of antibiotics were linked with a higher risk for several birth defects: nitrofurantoins and sulfonamides, sometimes called "sulfa drugs," which are prescribed for urinary tract and other infections.
US NEWS and WORLD REPORT
Women whose children had anencephaly, a fatal malformation of the skull and brain, were three times more likely to have taken sulfonamides, the study found. Sulfonamides were also tied to an increased risk for such heart defects as hypoplastic left heart syndrome and coarctation of the aorta, choanal atresia (a blockage of the nasal passage), transverse limb deficiency and diaphragmatic hernia, an abnormal opening in the diaphragm that results in severe breathing difficulties.
Nitrofurantoins were also associated with multiple birth defects, including anophthalmia and microphthalmos (eye defects) and several congenital heart defects. Mothers whose children were born with a cleft lip or cleft palate were twice as likely to have taken nitrofurantoins, the study found.