Expecting twins? Check out our list of early twin pregnancy symptoms

If your mother or grandmother was pregnant with twins or more in the 1960s, she may not have known until the doctor said, "Whoops! Here comes another one," in the delivery room.

Today, the widespread use of ultrasound virtually eliminates the possibility that a mother of twins or more wouldn't find out ahead of the delivery.

The following are some of the common signs mothers of twins or multiples report early in their pregnancy:

Early Weight Gain - Moms of twins typically gain five to ten pounds during the first trimester of their pregnancy. (Single pregnancy weight gain is about two to five pounds). The extra weight accounts for the increased blood level and uterine size needed to carry your twins.

Weight gain will differ for each person and may depend on your height, body type, pre-pregnancy weight and whether or not it's your first pregnancy. But if you look noticeably pregnant in the eighth or tenth week, there's a chance you may be carrying twins or more.

Severe Morning Sickness - Many women pregnant with twins report having morning sickness when they didn't in previous pregnancies or much more severe symptoms. Of course, if this is your first pregnancy, you won't know what is normal for you. But if you are experiencing severe morning sickness along with some of the other symptoms on this page, you may want to check out the possibility of a twin pregnancy with your doctor.

Extreme Fatigue - Fatigue is a common complaint for any pregnant woman. However, women pregnant with multiples often report being exhausted in their first trimester since their body must work overtime to support more than one baby.

Two Heartbeats - Early in your pregnancy, your doctor may let you hear your baby's heartbeat, using a handheld Doppler system. This device uses harmless sound waves to amplify fetal heart sounds. In some cases, an experienced physician may detect more than one heartbeat, indicating a multiple pregnancy. Diagnosis of a multiple pregnancy this way, however, is pretty rare.

Abnormal AFP Test Results - Your doctor may refer to this screening, usually performed in the second trimester, as maternal serum screening or the triple marker screen. A twin pregnancy can produce an unusually high or positive result.

Early Fetal Movement - Some mothers of twins or multiples report feeling early or unusually strong fetal movement. On its own, this doesn't necessarily mean it's twins or more but it could be an indicator if you're experiencing other symptoms as well.

Measuring Large - Most doctors will measure the height of the uterine fundus (from the top of the pubic bone to the top of the uterus) as an indicator of the baby's gestational age. A women pregnant with twins or more may measure larger earlier in her pregnancy. However, like weight gain, other factors may increase this measurement.

Ultrasound Confirmation - The best way to confirm if you're having twins or more is to have your doctor perform an ultrasound. Most doctors routinely perform an ultrasound in the second trimester of pregnancy. You may very well be surprised to find out that you're having twins or more during your first ultrasound. (I almost fell off the table when the technician said, "We'll call this one twin A and this one twin B.")

Talk to your doctor about your symptoms if you suspect you might be having twins or more. Like most things in pregnancy, symptoms can vary widely from woman to woman.

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