Methotrexate is a medication used to treat various types of cancer and autoimmune diseases such as rheumatoid arthritis and psoriasis. It works by slowing down or stopping the growth of cancer cells and suppressing the immune system. However, its use during pregnancy is a matter of concern due to its potential teratogenic effects, meaning it can cause harm to the developing fetus.

According to Medicines in Pregnancy, Methotrexate is contraindicated during pregnancy, especially during the first trimester, as it can cause severe congenital malformations, miscarriage, and fetal death. If a woman becomes pregnant while taking Methotrexate, it is essential to discontinue the medication immediately and seek medical advice. Women of childbearing age should use effective contraception while taking Methotrexate and for at least six months after stopping the medication.

A study published in the Journal of Clinical and Diagnostic Research [3] also highlights the potential risks of Methotrexate during pregnancy. The study suggests that Methotrexate can cause structural abnormalities in the fetus, including craniofacial malformations, limb defects, and central nervous system anomalies. The study further recommends that women who are planning to conceive should stop taking Methotrexate at least three months before trying to conceive.

In conclusion, Methotrexate is contraindicated during pregnancy, especially during the first trimester, due to its potential teratogenic effects. Women who are planning to conceive should stop taking Methotrexate at least three months before trying to conceive. If a woman becomes pregnant while taking Methotrexate, it is essential to discontinue the medication immediately and seek medical advice.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/METHOTREXATE
[2] https://www.medicinesinpregnancy.org/Medicine--pregnancy/Methotrexate/
[3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4617640/