A number of factors can impede your ability to get pregnant even after having had a child in the past. The most common issue is your current age. If you had a child in the past and you are now over the age of 35 years, your ability to get pregnant may be decreased. You may also have developed a problem with your ability to ovulate consistently and/or a polyp or fibroid in the uterine cavity that may impact an embryo's ability to implant and thrive. Also, your male partner may have a sperm abnormality that has caused a decrease in his sperm count, motility or shape. If you are at all concerned consult your HCP.