Marjorie Keller was a major American experimental filmmaker from the 1970s until her untimely death in 1994 at age 43, though in keeping with our habitual neglect of avant-grade cinema, none of her work is even listed on the Internet Movie Database. This lyrical and provocative documentary (1977) may be her best-known film, a graphic examination of a friend’s natural childbirth that offers a feminine corrective to the similarly themed Window Water Baby Moving (1959) by her mentor Sam Brakhage. Whereas Brakhage idealized motherhood and the “magic of childbirth,” Keller emphasizes the pain (as well as the joy) of the process: using grainy Super-8, extreme close-ups, and nonlinear editing, she follows an expectant mother from late pregnancy through nativity in a precise six-part structure. The effect is one of impressively controlled chaos.