Hi, Thanks for using the HCM. I am happy to address your questions, it is a category C drug, animal reproduction studies have shown an adverse effect on the fetus but no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks. Use of medications affects fetal development and causes anomalies if taken during the first trimester. During entire pregnancy, medications can be prescribed if the benefits of taking them are greater than the risks involved. The risks are high if mother gets infected during first and second trimester. The effects in fetus include constellation of symptoms constituting a syndrome that includes growth retardation, microcephaly (abnormally small head), cataracts, glaucoma, microphthalmia (abnormally small eyes), cardiovascular malformations, hearing loss, and mental retardation etc. Be in regular monitoring and follow-up with your treating doctor and report any new/abnormal symptoms immediately. Take care . Hope I have answered your query. If you have any further questions I will be happy to help. Thanks