(ABC NEWS) Spend 10 minutes on the phone with Dr. Susan Robinson, an obstetrician-gynecologist who specializes in providing women with third-trimester abortions, and the name Aron Ralston will invariably come up. He’s the mountain climber who was trapped in a canyon in Utah after a boulder crushed his right hand. He was pinned down by the boulder for five days (the film “127 Hours” is based on his story) until he realized the only way he could get free would be to cut off his hand.

It’s a graphic, horrific image, but Robinson says it’s the best analogy she can think of to describe women who are pregnant in their third trimester and “have thought about it deeply, consulted their conscience, wrestled with the ethics, and decided the best thing for themselves and their families is to have an abortion.”

“People think you choose an abortion like you choose red or green shoes, or a flavor of ice cream,” Robinson told ABC News. “But in fact, they [the women I see] need an abortion the way Aron Ralston needed to cut his hand off.”

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