MiniMi is a test that can be done from as early as 10 weeks of pregnancy to determine whether an unborn baby is a girl or boy. The test is done by taking a blood sample from the expectant mother. During pregnancy, DNA from the baby’s placenta is present in the mother’s blood. The placenta and the baby are made from the same cells at conception, so you are testing the same DNA from the baby by testing the placental DNA from the expectant mother’s blood.