Updated August 30, 2014.

Question: Why would I need a first trimester ultrasound?

Answer: For the most part, the majority of women will not need an ultrasound in the first trimester. If you do need an ultrasound it is because your doctor or midwife thinks that there may be a problem. It might be a suspected miscarriage or bleeding or the need to get an accurate gestational age.

You might need an ultrasound if:

• If you are bleeding or spotting.
   
  

• If you have a history of ectopic or tubal pregnancy.
   
  
• If you don't know the first day of your last menstrual cycle or establish a due date.
   
  
• To confirm a diagnosis of multiples (twins or more).
   
  
• To check for the presence of a heart beat or gestational sac.
   
  
• To check on pelvic pain or ovarian cyst.
   
  
• Other reasons as ordered by your doctor or midwife.

What your practitioner is looking for:

Your doctor or midwife may be looking for something specific during an ultrasound. It may be to rule out a problem or to diagnose something like a twin pregnancy. They may also be looking for your baby's heart beat, they will measure your baby from crown to rump length (CRL) if possible, they will count how many embryos are in the uterus and how many are viable. Be sure to ask questions about your ultrasound if you're not sure what is going on or what they are looking for during the ultrasound.

One of the hardest parts of early ultrasounds is that they may not give you complete answers. Sometimes your ultrasound will need to be repeated within a few weeks.

If you have had an abdominal ultrasound your practitioner may request a transvaginal ultrasound for a more accurate picture.

First Trimester Ultrasound Gallery