Those heterosexual couples who have been trying to get pregnant for more than 12 months without success, the recommendation is to visit a fertility specialist. He/she will be in charge of carrying out fertility studies in case there could be any alteration that may be hindering the pregnancy.
In the case of women older than 35-37 years, it is advisable to go to the specialist when about 6 months have passed. A woman's ovarian reserve, that is, her available number of eggs, decreases drastically after the age of 35. Therefore, the probability of pregnancy is lower.