How long should women try to get pregnant before calling the doctor?

6-12 months. In most cases, one should try for 12 months before seeking any help, though if you are over 35 you may want to cut that to only 6 months. At 40, i would get help pretty quickly. It is worthwhile to see your ob/gyn and tell them you are trying to get pregnant, as there is a number of things that they may want to talk to you about.