The chances of having a twin pregnancy are about 1%. Twins can be identical, about 1/3 are, which means that they form from one egg. Or, they may be fraternal, non-identical, which means they came from two separate eggs. Twin pregnancies are high risk. These risks include:1. Premature labor2. Miscarriage3. Having a difficult labor4. Developing pre-eclampsia.5. Developing anemiaToday, twins are usually diagnosed at the time of ultrasound. If there is no ultrasound done, you may become suspicious for twins if the uterus is growing too rapidly. Many women discover twins at the time of delivery, which surprises not only the parents, but the doctor as well!The greatest risk in multiple pregnancy is premature labor. If you are having a multiple pregnancy, you must be closely watched by your doctor. Your physician is there for you, so if there are any questions or concerns, you must bring them up. Following your doctor's recommendations will help lower the risks involved in having twins.