According to ASRM ,Success varies with many factors. The age of the woman is the most important factor, when women are using their own eggs. Success rates decline as women age, specifically after the mid-30’s.  Part of this decline is due to a lower chance of getting pregnant from ART, and part is due to a higher risk of miscarriage with increasing age, especially over age 40.  

The NICE fertility guideline, recommends that women under 40, who have been trying to get pregnant for 2 years, should be offered 3 full cycles of IVF. For women aged between 40 and 42, who have been trying for 2 or more years, and have not previously received IVF or shown evidence of low ovarian reserve, NICE recommends 1 full cycle of treatment.