Weight Gain

• Though it's normal for all pregnant women to put on some weight during pregnancy, mothers of twins put on a more excessive amount.
  
  

Gestational Age Measurements

• If you are measuring larger than the regular gestational age measurements, this may be because your uterus has to expand further in order to carry two babies.
  
  

Alphfetoprotein (AFP) Test

• An alphfetoprotein (AFP) test measures the amount of protein secreted by fetal liver in the mother's blood. When carrying more than one baby, the amount found in the mother's blood may be extraordinarily high.
  
  

Extreme fatigue

• All pregnant women feel very exhausted. However, if you are feeling abnormally fatigued, it could be a sign that you are carrying twins.
  
  

Family history

• If you have a family history of having twins in your family, your chances of having them will be higher, too.