3 syllables:
pregnancy, pregnency, regnancy

5 syllables:
mask of pregnancy, tubal pregnancy

7 syllables:
abdominal pregnancy, ovarian pregnancy

2 syllables:
thessaly

3 syllables:
severally, splendidly, pleasantly, messily, tendency, ebony, pedigree, credibly, gemini, venally, leprosy, prelacy, lengthily, elegy, readily, tenantry, weaponry, helplessly, equity, zestfully, remedy, breathlessly, brevity, revelry, flexibly, melody, steadily, entity, jealousy, restfully, enemy, seventy, entropy, tensity, peasantry, clemency, velvety, threnody, sensibly, devilry, chemistry, pedantry, legacy, bestially, cecity, necropsy, sesame, zealotry, mentally, density, dreadfully, helpfully, testily, specially, embassy, tenancy, pleasantry, centrally, kennedy, deputy, secondly, enmity, legatee, felony, preciously, recipe, ecstasy, especially, debauchee, specialty, presently, destiny, heavily, heavenly, medically, endlessly, empathy, jealously, chemically, penalty, benghazi, dextrously, ectropy, emigree, evilly, fecklessly, jejunely, legibly, lemony, lenity, melanie, pebbly, pederasty, penally, resiny, self-pity, selflessly, senselessly, sentiency, stephanie, tepidly, trenchancy, trepidly, vengefully, yemeni, zestily

4 syllables:
theosophy, incessantly, rebelliously, transcendency, detestably, acceptably, resplendently, extremity, ascendancy, nonentity, mastectomy, expectancy, identity, necessity, dependably, lamentably, successfully, inequity, discrepancy, sequentially, unsteadily, lobectomy, ascendency, preferably, serenity, fidelity, unpleasantly, nephrectomy, potentially, death penalty, tremendously, essentially, flux density, desperately, schenectady, lumpectomy, intrepidly, ostensibly, sententiously, complexity, splenectomy, insensibly, telemetry, respectfully, respectably, hegemony, generally, inflexibly, dependency, supremacy, anemone, longevity, repentantly, ineffably, perplexity, vasectomy, resplendency, solemnity, contemptuously, amenity, federally, intensity, heredity, perceptibly, convexity, incredibly, integrity, allegedly, indemnity, incessancy, separately, telepathy, licentiously, low density, regrettably, thrombectomy, tentatively, infectiously, penelope, acephaly, confessedly, defencelessly, domenici, forelady, illegibly, immensity, impendency, impetuously, inclemency, jack kennedy, lieutenancy, neurectomy, perplexedly, polemically, pretentiously, professedly, quiescency, refreshfully, relentlessly, revengefully, shell entity, unhelpfully, vulvectomy, with empathy

5 syllables:
tonsillectomy, orchidectomy, geochemistry, hysterectomy, eventually, sympathectomy, life expectancy, sentimentally, exceptionally, consequentially, confederacy, biochemistry, accidentally, mastoidectomy, independently, reverentially, oophorectomy, white supremacy, professionally, stapedectomy, orchiectomy, pneumonectomy, salpingectomy, thyroidectomy, disrespectfully, appendectomy, penitentially, irreverently, macrencephaly, abstemiously, rhytidectomy, incidentally, intemperately, open sesame, providentially, high fidelity, prostatectomy, unacceptably, deferentially, photochemistry, independency, conscientiously, embolectomy, microcephaly, fundamentally, vapor density, anencephaly, reprehensibly, unsuccessfully, acrocephaly, change integrity, change intensity, clinocephaly, coalescency, create mentally, detrimentally, drunken revelry, field intensity, half-intensity, high-fidelity, hydrocephaly, intumescency, laminectomy, laryngectomy, line of destiny, macrocephaly, megacephaly, meniscectomy, mortal enemy, mountain ebony, nanocephaly, naval weaponry, of necessity, scaphocephaly, school of dentistry, sigmoidectomy, unforgettably, unpretentiously, unrepentantly

6 syllables:
cholecystectomy, unconventionally, coincidentally, biogeography, unintentionally, environmentally, radiochemistry, physical chemistry, simple mastectomy, impetuosity, manifest destiny, interdependency, electrochemistry, organic chemistry, cercopithecidae, experimentally, cosmetic dentistry, inconsequentially, adrenalectomy, immunochemistry, relative density, adenoidectomy, anas penelope, appendicectomy, change of integrity, genus penelope, militant tendency, ovariectomy, panhysterectomy, pedal extremity, unsentimentally

7 syllables:
radical mastectomy, inorganic chemistry, magnetic flux density, paleogeography, total hysterectomy, department of chemistry, executive clemency, feeling of identity, john fitzgerald kennedy, magnetic intensity, suprarenalectomy

8 syllables:
radical hysterectomy, conformational entropy, interpersonal chemistry

10 syllables:
modified radical mastectomy