Thank you for your interesting question. In pregnancy, great caution needs to be taken with medications, and I recommend that you consult with your Obstetrics and Gynecology doctor
for further information. To answer your question, lymecycline is a type of tetracycline antibiotic that can potentially affect the fetus. Tetracyclines are able to cross the placenta and are known to accumulate in the developing long bones and teeth. Although there do not seem to be any significant long-term effects on growth, tetracyclines can cause permanent grayish discoloration of the teeth in the developing fetus. Fortunately, tetracyclines are generally considered to be safe when taken within the first trimester of pregnancy (in the first 12 weeks). If taken later than this, the negative effects described above may be observed. For this reason tetracyclines are a class D medication in pregnancy, which means that we have clear evidence of risk to the fetus, but in the right circumstances the benefit to the mother may justify its usage. Common practice is to try and avoid tetracyclines during pregnancy and to only resort to them as second-line antibiotics. As mentioned previously, please consult with your Obstetrics and Gynecology physician for further information regarding the safety of tetracyclines and other medications during pregnancy.