IVF does not always result in pregnancy. In good centers, world over, success rate of one IVF cycle is around 40%.
In general, younger women have a higher chance of success. Success rates decrease dramatically in women over 40. IVF can be a physically and emotionally demanding process. Most of the time, infertile couple is very anxious and high level of emotional disturbance in the female partner hampers the outcome of IVF Cycle.
Anyone undergoing IVF needs a lot of emotional support and counselling to tide over the stress of IVF process and its un-assured results.