Ah, the joys of childbirth . . . (Mike Ansell/FX)

Actually, there’s been a lot of mystery this season about exactly who or what is growing inside the womb of poor Mrs. Harmon. Tonight we will hopefully find out.

In order to prepare for that event, here’s some idle speculation about what could happen when Vivien presumably goes into labor tonight on “American Horror Story.”

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I’m not going to delve into the logistical matters hinted at in the preview for tonight’s episode (see below) regarding whether Vivien gives birth in the Murder House, at her sister’s house or in some other location. (For the record, my money is on the Murder House.)

No, let’s purely try to figure out what will happen when Vivien Harmon starts to push and a couple of (fingers crossed) babies arrive into this world. Here are the possibilities:

Vivien gives birth to two totally normal kids

Maybe both of the twins are totally fine and healthy. And one of them is a sweet blond cherub who looks a lot like Tate. If that happens, I reserve the right to refer to that baby as Little Man Tate.

Vivien gives birth to two normal-looking kids. But one of them turns out to be evil.

We’ll refer to this as the Bad Seed Scenario. I think the likelihood of some variation on this occurring is high.

Vivien delivers at least one disfigured child who looks like Bo.

We know that all of Constance’s children had some issues, either physical, psychological or both. It’s quite possible that history will repeat itself via Vivien.

Vivien becomes the mother to at least one baby who comes out of her uterus in a rubber suit.

I realize that sounds a little crazy, but let’s not forget that this is “American Horror Story,” a show in which a rubber-suit-wearing ghost raped his girlfriend’s mother and is still dating that girlfriend, who is also now a ghost. All things are possible.

Vivien has an 11th-hour miscarriage.

That would be sad, as well as a narrative letdown after all the build-up about the birth. I don’t see this happening to both babies, but I can envision a scenario in which she loses one of the twins. That would heighten the tension as various parties — the Harmons, Constance, Zach Quinto, Nora Montgomery, Zombie Kate Mara — start jockeying for custody.

Vivien delivers the babies, but dies during childbirth

I am convinced that before the season finale ends next week, all of the Harmons will have died, setting up a scenario in which they all act as ghosts during season two. It’s entirely possible Vivien could pass on next, especially given all the strain she’s been under, what with the pregnancy, and Zombie Kate Mara trying to kill her, and her daughter dying even though Vivien doesn’t realize it, and having to stay in an exceedingly bleak mental hospital. I hope not, though. The poor woman has been through enough.

Do any of these outcomes sound plausible, plausible being a relative term in the “American Horror Story” universe? Weigh in with your own childbirth predictions by posting a comment.