Ultrasound scans are an essential part of infertility testing and fertility treatment. If you’ve had a child before, you may be familiar with the kind of ultrasound done during mid to late pregnancy. Even if you’ve never had a child, you may have seen pregnancy ultrasound exams on movies or television. Or, perhaps, a friend or family member may have shared an ultrasound image of their unborn child with you.
Ultrasounds done during mid to late pregnancy are usually abdominal ultrasounds. In other words, a transducer (a device that emits and receives sound waves for an ultrasound) is moved around over the abdomen.
For fertility testing and treatment, the majority of ultrasounds are done transvaginally—that is to say via the vagina—with a slender specialized wand.
The ultrasounds are not painful, though they can be slightly uncomfortable.
During infertility testing, ultrasound scans can provide information on the ovaries, endometrial lining, and uterus. Specialized ultrasounds can be used to evaluate ovarian reserves, the uterine shape in more detail, and whether the fallopian tubes are open or blocked.
During fertility treatment, ultrasound is used to monitor follicle development in the ovaries and the thickness of the endometrial lining. Ultrasound is also used during IVF for egg retrieval, to guide the needle through the vaginal wall to the ovaries. Some doctors use ultrasound during embryo transfer.
If you get pregnant, your reproductive endocrinologist will likely order a few ultrasounds before transferring you back to your regular OB/GYN.
Infertility Ultrasound Scan Basics
Ultrasound scans work by using high-frequency sound waves to create an image of your internal organs. You won’t be able to hear the sound waves.
A transducer is a device used during an ultrasound to emit and receive these high-frequency sound waves. During fertility testing and treatment, the technician is likely to use two different kinds of transducer devices: one that is used for abdominal ultrasound and a second that is used transvaginally.
During an abdominal ultrasound, a gel is squirted over your abdomen. Then, the transducer is gently moved over the abdomen. The gel makes it easier for the transducer to slide around over your skin.
During a transvaginal ultrasound, the transducer is shaped like a slender, long wand. A condom is placed over the wand and a lubricant gel is generously squirted over the condom.
The technician will hand you the handle of the transducer wand, so you can place the transducer gently inside of your vagina as far as it will comfortably go. You will then hand off the handle to the technician, who will conduct the exam.
Sound waves are emitted by the transducer. They echo (or bounce back) when they hit your internal organs. The ultrasound machine interprets these signals and turns them into a digital image.
Before an abdominal ultrasound, your doctor will likely ask you to drink several cups of water in the hours before your exam but request that you don’t relieve yourself if you feel the need to urinate. (You probably will feel the urge to go!)
A full bladder pushes your intestines out of the way, so your reproductive organs are easier to see. Once the abdominal ultrasound is finished, you’ll be able to use the bathroom.
However, to see the detail needed for fertility testing and treatment, transvaginal ultrasound provides even better imagery.
The transvaginal transducer tip is placed right below the cervix, which is closer to your reproductive organs.
Beside the abdominal and transvaginal ultrasound, there are other specialized ultrasound scans that your doctor may request.
- Antral follicle count ultrasound: this is done with the usual transvaginal ultrasound device, but requires special training for the technician to complete accurately.
- Antral follicle count ultrasounds can help determine your ovarian reserves and possibly help diagnosis polycystic ovarian syndrome (PCOS). You may or may not have an antral follicle count exam as part of your basic fertility workup.
- This may also be scheduled separately or at the same time as a general ultrasound scan.
- 3D ultrasound: Most ultrasound imagery is two-dimensional. Advancing technology now can also generate three-dimensional images.
- This allows for better detection of some uterine abnormalities and fallopian tube problems that are not visible on a typical 2D ultrasound scan.
- Sonohysterogram: A sonohysterogram is a specialized ultrasound that involves transferring a saline solution into the uterus via a catheter. The saline solution fills your uterus, making it easier to visualize the shape and any possible adhesions within.
- A sonohysterogram may be done during a basic fertility workup, but is more commonly used for specific situations.
- Hysterosalpingo-contrast sonography (HyCoSy): This is similar to a sonohysterography, except a dye or a saline solution mixed with air bubbles is used to determine whether the fallopian tubes are open or blocked.
- It’s more common for doctors to evaluate whether the fallopian tubes are open with an HSG, which is a specialized X-ray.
- The advantages of having an HyCoSy over an HSG are that the HyCoSy may cause less discomfort than an HSG.
- HyCoSy doesn’t require radiation or iodine exposure.
- An HyCoSy may be done at the same time as a general ultrasound exam (which would mean one less appointment).
What Your Doctor Is Evaluating With Ultrasound
Here is what your fertility doctor is evaluating with an infertility ultrasound scan.
General position and presence of the reproductive organs: Is everything that should be there present? Is everything in the correct area?
It seems like a very basic question, but some women are born without the ovaries or their uterus.
The ovaries: The ultrasound tech will look at your ovaries. She will take note of their size and shape.
She will also look for evidence of both normal and not normal cysts on the ovaries. Many small cysts that look like a pearl necklace may indicate polycystic ovarian syndrome. The presence of a larger endometrioma cyst may indicate possible endometriosis.
In rare cases, a mass that is not a cyst may be found on the ovaries.
Antral follicle count: This may be part of a general infertility ultrasound scan or may be scheduled separately. Antral follicles are a specific kind of follicle found in the ovaries. They are part of the egg/oocyte lifecycle.
A very low antral follicle count may indicate poor ovarian reserves. An unusually high antral follicle count may indicate PCOS.
The uterus: The ultrasound tech will note the uterine size, shape, and position.
These can’t always be seen with a regular ultrasound. Further evaluation may require a sonohysterogram or a hysteroscopy.
Endometrium thickness: The lining of the uterus, the endometrium, thickens and changes as your menstrual cycle progresses.
The technician will look for healthy indications that the endometrium is at the stage it should be, based on the day of your exam.
The ultrasound tech will also measure the thickness of the endometrium. It should be thin before ovulation and thicker after ovulation.
Possibly fallopian tube problems: A basic ultrasound isn’t capable of capturing healthy fallopian tubes. However, a fallopian tube may be seen with a regular 2D ultrasound if it is swollen or filled with fluid, which can occur with a hydrosalpinx.
A basic ultrasound can’t determine if the fallopian tubes are clear and open. To evaluate whether the tubes are open or closed, your doctor will most likely order an HSG.
However, with a specialized ultrasound known as a hysterosalpingo-contrast sonography (HyCoSy), your doctor may be able to detect whether the tubes are blocked or not.
Possible evidence of adhesions: By gently pressing on the reproductive organs with the transvaginal transducer, the technician can see if the organs move freely and as they should, or if they seem to adhere to each other.
The tech may also use the ultrasound wand to gentle push at the ovaries, to see how they move around in the pelvic cavity. Ovaries that seem stuck to each other are sometimes called “kissing ovaries.”
Adhesions may prevent the reproductive organs from freely moving. Adhesions can form from a previous pelvic infection or from endometriosis.
Blood flow to reproductive organs: if your doctor is using color Doppler, the technician may be able to evaluate blood flow around a cyst or mass. This can help distinguish between a healthy cyst, an endometrial cyst (endometrioma), or an ovarian tumor.