drop, cry, descend, breathe, labor, pass through (the birth canal), enter the world, exit (the womb)

tear, grip, clench, rip, contract, thrust, push, heave, squat, ripple, sweat, brace, flush, shriek, birth, squeal, bleed, pace, pant, whimper, give birth, bellow, roar, tremble, dilate, soften, ooze, spurt, gush, focus, open, pulse, erupt, progress, release, huff, inhale, rupture, gasp, cry out, quake, throb, exclaim, wail, moan, writhe, exhale, groan, crown, draw (in breath), rock (pelvis), lean on/back, blow (air), labor