An ultrasonic view of fertility

October 30, 2009

“Today might be the day,” says an anonymous U of S professor, walking towards a research clinic in the old wing of Royal University Hospital. “Angie said if we can catch the event on the ultrasound, I will have a very famous ovary.”

By Mark Ferguson

A famous ovary?

It turns out that after 12 years of studying female fertility, Angela Baerwald, an assistant professors in the Department of Obstetrics, Gynecology and Reproductive Endocrinology, has never captured real-time footage of ovulation using ultrasound. She says there has been footage collected from researchers in the US, but the ovulation event was induced by hormone drugs. Today, the professor will serve as Baerwald's research volunteer, and the two are hoping for good timing with her natural cycle.

“We're on stand-by now,” says the 35-year old volunteer, pointing to her lower left abdomen. “Right now I can feel a dull pinch and I'm waiting for it to get more intense. We have anywhere from 18 seconds to 18 minutes after you feel it.”

Baerwald welcomes us into her office when we arrive and asks my friend how she is doing. The two have been seeing each other three times a week for nearly two months - enough time to gather data from two or three complete ovulation cycles. The investment in time is substantial for her test subjects, but the professor is more than happy to help a colleague.

“I'm really proud to be a part of this research. I want to help out Angie.” she says. “I think this is important.”

Baerwald's research focuses on follicles, the tiny fluid-filled sacks that contain the egg, or oocyte, in the ovary. For 60 years, it was believed that one follicle grew at one time during a cycle, but her research is proving otherwise.

“Originally, it was thought that one follicle takes two weeks to reach maturity, and then it is released with ovulation. But now we know this is different.”

After an initial study in 2003, Baerwald found that most women have two follicle waves per cycle, and in some cases, even three. She does not know yet whether the volunteer is a “two or a three”. She is hoping today's ultrasound on the volunteer, her 35th test subject in the study, will shed some more light.

Baerwald leads us into her lab and dims the light, so the ultrasound screen shines bright and clear. Her subject prepares herself behind a curtain, slipping on a hospital gown, and pops herself up on the ultrasound examination chair.

“Can you see these?” asks Baerwald, pointing to the screen. “The black circles you're seeing are follicles. Basically, they are fluid filled bubbles and the egg is inside the follicle.”

The screen is filled with black circles as Baerwald maneuvers the ultrasound wand. About 10 follicles are visible, with two substantially larger than the others.

 There will be anywhere from 10 to 20 follicles growing inside each ovary per wave and they are all competing, Baerwald explains. Eventually, one will grow larger than the others (between 18 and 22 mm), before it is released. The number of follicles and the cycles change as women grow older which is why Baerwald is trying to include older women who are nearing menopause in her study.

About 10 minutes into the ultrasound, Baerwald decides there is enough data for today, but sadly, no ovulation footage. The volunteer, however is healthy as can be, she says.

“Our goal is to change the model of follicular development. This will change the information in medical textbooks and the knowledge of practising clinicians.”

After saying goodbye to Angie, the professor walks out of the hospital feeling a bit disappointed her almost-famous ovary did not perform for the camera, but she thinks one of these days, they might just get lucky.