there is nothing that you can do naturally to increase your chances of having twins. fertility drugs and increasing age do however increase the chance of twins. fraternal twins (non-identical) can have a genetic component so if non-identical twins run in your family then you may be more likely to have twins. this happens when two eggs are fertilized by two different sperm. identical twinning happens spontaneously after the one egg has been fertilized by one sperm. although it can be fun to have twins it is actually quite risky. there is a higher chance of miscarriage preterm labor fetal death pre-eclampsia gestational diabetes and cesarean section. <link>
how can one increase probability of getting twins?