Twins can be detected around 6-7 weeks of pregnancy and can be determined by having an ultrasound. For women who usually have regular periods, an ultrasound at 6 weeks of menopause can usually tell if it is a singleton or twins, and in the case of twins, it can also determine their chorionicity, which means that you can tell if it is monozygotic or dizygotic. Monozygotic twins two fetuses are genetically, sexually, and look the same, and dizygotic twins two fetuses are genetically, and look different. At around 50 days, you can determine whether both twins have buds and hearts. Only if both have buds and hearts are true twins, if one of the fetuses stops, it cannot be considered as true twins. Therefore, pregnant women who want to know whether they are carrying a single child or twins can have an ultrasound at 6-7 weeks of pregnancy to determine this. Twins require high nutrition and are prone to preterm labor, so after pregnancy, they must be monitored as a high-risk pregnancy, go to the obstetrics clinic in time for pregnancy checkups, and under the doctor’s management plan do all the tests in pregnancy to ensure the normal development of the fetus.