Free Unplanned Pregnancy Information

What Is An Ultrasound?

Ultrasound technology, or sonography (from the Latin sonos for sound and the Ancient Greek –graphō for writing), uses high-frequency sound waves to see, or visualize, things that we can’t look at with the naked eye.

It was developed by a group of obstetricians (pregnancy researchers) from Glasgow, Scotland in 1956. Long before that, an Italian scientist began studying the use of echolocation, a form of ultrasound, in bats. Lazzaro Spallanzani learned that bats used high-frequency screeches to “read” their environments through echoes. After the Titanic sunk, Paul Langevin, a French physicist, used ultrasound technology to detect icebergs hidden below the ocean surface. Soon after World War II, doctors from America and Europe began using ultrasound technology to diagnose medical conditions. Even so, the World Health Organization (WHO) estimates that “75% of the world’s population has no access to any diagnostic imaging,” or ultrasound, technology.

How Do Ultrasounds Work?

Essentially, high-frequency sound waves can pass through your belly, but will bounce off internal organs and structures in significant ways. Using a sophisticated array of machines, ultrasound technicians can “read” the echoes produced by these bouncing sound waves, and determine the size, shape, and form of what’s going on inside your womb.

Beyond giving us an accurate picture of your growing baby, ultrasounds are used to detect problems, like birth defects and breech positioning, determine your baby’s sex, and rule out the possibility of an ectopic pregnancy. An ectopic pregnancy occurs when an embryo implants somewhere other than in your uterus. To learn more, visit WebMD.

What Should I Expect?

Ultrasounds are painless, so don’t worry about that. Still, your doctor may tell you not to eat or drink for several hours before your appointment.

On the other hand, you could be asked to drink a lot of water, and not urinate, to ensure that your bladder is full. Why? If the transducer (the thing that emits the sound waves) is placed on your stomach, as in a routine ultrasound, the fetus will show up right in front of your bladder. When your bladder is full, it creates a large, dark backdrop, increasing contrast and a clearer image of your baby.

An ultrasound technician will apply a harmless, water-based gel to your stomach, which helps the transducer glide over your skin without pain. Then the transducer is simply rubbed across your skin and a picture of your growing baby appears on a little screen. It’s really easy, and totally harmless. Most ultrasounds take around half an hour.

When Should I Schedule My First Ultrasound Appointment?

If you’ve been pregnant before, and experienced complications, your doctor may schedule an early ultrasound – to verify whether or not you may have complications during your current pregnancy. An early ultrasound generally takes place between six to ten weeks from the date that you learn you are pregnant.

In most cases, your healthcare provider will recommend a vaginal, or “transvaginal,” ultrasound at this point, rather than the kind that involves contact to your belly. A transvaginal ultrasound creates more accurate images of the uterus and ovaries.

How Many Ultrasounds Will I Have?

If your pregnancy has been complication-free thus far, you’ll probably have two ultrasounds total. The first, a “dating” ultrasound, generally occurs around 10 to 14 weeks after conception, and determines:

the approximate date of labor and delivery, by measuring the length of your baby
whether or not you are carrying twins, triplets, or more children
whether or not your baby’s heartbeat is normal

Your second ultrasound, which usually occurs during the second trimester, is more of a check-up, and can show you images of your baby’s head, spine, heart, face, arms, and legs.