When it comes to IVF consultation, people are of course concerned about what the success rate is, and they must also ask: which season of the year is the most suitable for IVF and has the highest success rate? Is spring the best? We know that when humans conceive normally, they are more concerned about the season in which the child is born. There are studies by foreign scholars that the season when humans are most likely to conceive naturally is not spring as we think, but the season with the longest sunshine, which is summer. However, for IVF, there is no clear conclusion. We have analyzed the annual IVF pregnancies and found no significant differences in conception rates between the four seasons of the year. As we can imagine, IVF is performed in a laboratory where fertilization, embryo culture and transfer take place at a constant temperature of about 25 degrees throughout the year. Follicle development is also carried out medically and may be less affected by the season. Therefore, from the current information and clinical results, the success rate of IVF is not significantly related to the season, you just choose the season you prefer.