Taking drugs before pregnancy may not have any effect on the fetus, or may increase the chance of fetal malformation and miscarriage, depending on the metabolism of the drug and the type of drug to judge.
If you take the drug at a long interval before pregnancy, the drug has been completely metabolized in the body, and then you have intercourse with a man to get pregnant, it will not have any effect on the growth and development of the fetus.
If you take the drug at a relatively short interval before pregnancy, the drug is applicable during pregnancy, such as amoxicillin, etc., which can be completely metabolized in a relatively short period of time in the body, and will not pass through the placenta to affect the fetus, so it will not have any effect on the fetus.
Drugs taken at relatively short intervals before pregnancy, and the drug is prohibited during pregnancy, such as rifampicin, gentamicin, etc., the drug metabolism time is relatively long, can not be metabolized in time before pregnancy, the drug is absorbed by the fetus through the placenta, which may lead to fetal deformities, miscarriage and other risks.
Whether or not the drugs taken before pregnancy have an effect on the fetus should be considered on the basis of a number of aspects, and cannot be generalized.