The word menstruates is playable in Words With Friends™, no blanks required. Because it is longer than 7 letters, you would have to play off an existing word or do it in several moves.
Words With Friends™ Letter Score: 16
Highest Scoring Words With Friends™ Play In The Letters
Seven Letter Word Alert: (90 words)
artsmen, assumer, astuter, attunes, austere, earnest, eastern, ensears, ensures, entreat, entrust, estates, estrums, estuate, euaster, manures, martens, masseur, masters, matters, matures, meanest, measure, musters, mutants, mutates, mutters, natters, natures, nearest, neatest, nesters, netters, neuters, nutmeat, nutters, remates, renames, renests, reseats, resents, restate, restems, resumes, retaste, reteams, retests, retunes, sateens, saunter, seamers, seaters, senates, sensate, setters, smarten, smatter, stamens, staters, statues, stature, steamer, sterane, sternum, stratum, stratus, streams, streets, stunter, sunstar, surname, tantrum, tasters, taunter, tautens, teasers, tensest, tenters, tenures, ternate, tersest, testers, tetanus, truants, trustee, unmates, unreset, unrests, unseats, ureases