Actor Kim Kivens does not hold up a picture of an aborted late-term fetus in “What I Thought I Knew,” a solo show that opened Saturday at Minnesota Jewish Theatre Company. Playing a medical clinic employee, she describes what happens to the fetus in low-key, clinical terms.

It’s chilling. At Saturday’s opening, some audience members winced and recoiled.

But even as those details pass, there’s hardly any escape from the harrowing larger story that is coolly unspooled over the 100 minutes of Alice Eve Cohen’s autobiographical one-act play. Performed with immediacy, power and occasional humor by Kivens, and staged with effective simplicity by Jennie Ward, “What I Thought I Knew” takes us on a gripping ride even as it raises moral and practical questions.

Cohen, a New York-based writer and theater teacher who adapted this show from a best-selling memoir, had been told all her life that she was infertile. So she adopted a child, even as she keeps up a regimen that includes hormone treatments.

Now, at 44, she has an unexplained growth in her abdomen. Her doctors think it may be a tumor, something related to menopause. After a battery of tests, she finds out she is six months’ pregnant.

All sorts of questions arise.Cohen has had no prenatal care. Ultrasounds reveal a fetus with a number of complications. Cohen considers her options, from abortion to adoption to keeping the child. She often seems alone in her deliberations, though she has a partner — amusician who’s 10 years younger and always on the road — as well as her daughter, who is now 8.

There’s not much of a set on the stage of the Highland Park Community Center, where MJTC’s shows are performed. There’s a chalkboard on which the narrator writes chapter headings, and a floor lamp that represents Cohen’s 8-year-old.

Kivens starts the show by wheeling in an expandable table that contains a picnic basket, which has some sustenance for her. Then she takes us into the story, playing all the characters with their accents, gestures and idiosyncrasies.

A one-person play is one of the most daunting challenges an actor can take on. There is no scene partner to give the performer a cue or to serve as a crutch. The actor has to generate all the emotions herself. And she has to master reams of text, or at least flub her lines with honesty.

But the risks are worth it when you have a skilled performer like Kivens, who has performed some fetching characters at Children’s Theatre. She holds us spellbound, even if we grimace here and there. Understated and with assurance, she takes us inside the emotions that rock a confident woman whose assumptions about herself and her world are totally upended.

“What I Thought I Knew” is a very specific story. But there’s insight for any of us who might be blindsided by unexpected news.