I Am 36 Years Old And A Mother Of 2

I am 36 years old and a mother of 2 kids the last one is 5 months old. I had 3 pregnancies and the middle baby died from a heart condition and he was full term. I recently picked up that I am pregnant again and I want to abort as I cant 3 kids and I am also worried about the fact that this will be a 4th pregnancy and all 3 have been C-Sec. Please advise