How long it takes to have intercourse after the follicle is mature depends on the size of the follicle, generally the follicle grows to about 2cm is considered mature, at this time intercourse is easy to get pregnant. The size of the follicle varies from person to person, some people grow up to 1.8cm to be mature, some people can grow up to 2.2cm, this is a range of values. So as long as the follicle has grown to about 2cm 14 days before your period, it is the most likely time to have intercourse to get pregnant. For women who do not want to have children and need contraception, they should avoid having intercourse during this time, that is, 3-5 days before or 3-5 days after ovulation, which is relatively less likely to get pregnant, so as long as you are sure that the follicles are in the mature stage, you can have intercourse if you want to get pregnant.