You may consult a fertility physician (Reproductive Endocrinologist or REI) any time if you have difficulty conceiving. You can try for up to a year if you are 34 or under, or for up to 6 months if you are 35-39. See a REI right away if you are 40 or over, if you have irregular cycles, if you have had a previous ectopic pregnancy, chlamydia or Pelvic Inflammatory Disease, if you have had endometriosis or ovarian surgery, or if your partner has known sperm issues.