Ever wonder how Who's Afraid of Virginia Woolf would have played out if the baby had lived? Take a look at Tina Howe's uncomfortably provocative Birth and After Birth, currently at Off Broadway's Atlantic Theater Company. Her warring parents are cut from the same tattered cloth as Edward Albee's bitter George and Martha; and, as in Woolf, they get extra nasty when an unsuspecting couple comes onto their turf — especially when they take the focus off their precious child Nicky, the spoiled center of their universe. (The occasion is Nicky turning four, and the absurdity that follows is a very smart nod to Harold Pinter's Birthday Party). Nicky is played by Jordan Gelber, a 6-foot-plus actor with a booming baritone and a Pillsbury Doughboy belly. But the casting is no mere sight gag. Sure, Gelber sucking his thumb gets laughs, but it's actually a shrewd way of showing just how big of a presence this child is in his parents' lives; he's, in a way, larger than life. And as the adults around him begin to spin out of control, Nicky becomes more sedate, more thoughtful, smarter than his four years, and the subtle center of Howe's play. What might have been a meditation on the petty annoyances of parenthood is thus transformed into a daringly grotesque aria. It's a play that could only have been written by a mother —and by one who actually wrestled with the to-be-or-not-to-be-a-mother question herself. Go, squirm, and revel in your discomfort. (Tickets: telecharge.com or 212-239-6200)