Having twins can be a joy and a challenge. Conceiving twins is not a sure science, but there are a few things that you can do to increase your chances of having twins.
Know that a single, fertilized egg that splits in two will create identical twins. Each egg will develop into an individual, and both will be enclosed within the same placenta. The genetic makeup of the twins will be identical. Identical twins are always either both boys or both girls.
Know that fraternal twins are created when the female releases two eggs that both get fertilized and implant. These developing babies will each have a separate placenta. The genetic makeup of these twins will be different, just as if they were born at separate times. Fraternal twins can be of the same sex, or there can be one of each sex.
Take dietary supplements such as cassava root (a type of yam), dairy products and folic acid to slightly increase your chance of having twins.
Keep breastfeeding while you're trying to conceive the next child. Breastfeeding mothers conceive twins at a greater rate than mothers who have weaned their previous children.
Know that older women and women who are slightly overweight also have a greater chance of conceiving twins.
Realize that, overall, conceiving twins is largely a matter of luck.