All perfect praise be to Allah the Lord of the Worlds. May His peace and blessings be upon Prophet Mohammad and upon all his family and companions.
Resolution No.(
35) (23/12/1413) (13/6/1993) by the Board of Iftaa, Research and Islamic Studies states the following:
"If the fetus became four months old or more, then aborting it is impermissible, even if it was deformed. This is in case the doctors determined that it is likely to survive. However, if it endangers the mother`s life, then it is permissible to abort it. Moreover, if it didn`t become four months old, and it was confirmed that its deformity will make its life unstable, then it is permissible to abort it with the consent of both spouses."
If your situation (Asker`s) is similar to what is mentioned in this Resolution, then it is permissible for you to have an abortion. If it isn`t the same, then it isn`t permissible for you to have an abortion. And Allah The Almighty Knows Best.