Gwyneth Paltrow may have played a loonybird onscreen more than once (“Sylvia,” “Proof”), but this time she’s been wolfing down crazy pills with nary a camera in sight.

Paltrow and her Grammy-winning husband, Chris Martin, have reportedly shelled out perfectly good money to install “birthing pools” in both their New York and London homes so that Paltrow can give birth to the couple’s second child underwater.

Not that the idea of relaxing in a hot tub instead of being trussed up in hospital stirrups with the entire cast of “Scrubs” peering up your Baby Expressway doesn’t hold a certain appeal…but is this wise?

A friend of Paltrow’s is quoted as saying the birth will be “special” and “spiritual”, and that Gwyneth has done “loads of research” on the topic. Sounds like her research failed to unearth one fairly well-established equation: water + lungs = dead baby.

Better hit those books a little harder, Gwynnie…