Uterus
Non tumor
Dysfunctional uterine bleeding (DUB)

Author: Nat Pernick, M.D. (see Authors page)

Revised: 16 January 2017, last major update November 2011

Copyright: (c) 2002-2017, PathologyOutlines.com, Inc.

PubMed search: dysfunctional uterine bleeding [title]

Cite this page: Dysfunctional uterine bleeding (DUB). PathologyOutlines.com website. http://pathologyoutlines.com/topic/uterusdub.html. Accessed October 21st, 2017.
Clinical features
  • Definition: bleeding > 5 days of unknown cause in women of childbearing age (eMedicine #1, #2); a clinical term, not a pathologist term
  • Known causes: adenomyosis, anovulatory cycle, chronic inflammation, drugs with hormonal side effects, ectopic pregnancy, endocrine disorder, endometrial carcinoma (5% - 15% of postmenopausal bleeding), endometrial hyperplasia, endometrial polyp (5% - 15%), endometriosis, exogenous hormones, idiopathic stromal predecidualization in postmenopausal women, leiomyoma, luteal phase defect, malnutrition, obesity, ovarian granulosa-theca tumor, precocious puberty, pregnancy complication
  • May be due to degenerative changes in uterine blood vessels associated with atrophy
  • Can classify based on ovulatory or nonovulatory cycles:

  • If patient ovulates, may be due to inadequate proliferative phase, inadequate secretory phase, irregular shedding or membranous dysmenorrhea
  • Inadequate proliferative phase: disparity between clinical menstrual cycle date and microscopic changes (usually delayed morphologic changes of proliferation)
  • Inadequate secretory phase: discrepancy of 2+ days between microscopy and clinical cycle date; biopsy shows underdeveloped secretory endometrium or secretory and proliferative endometrium in same specimen; also irregular shedding; due to low progesterone; associated with infertility, amenorrhea; treat with hormones
  • Irregular shedding: bleeding 7+ days due to lag in shedding of secretory endometrium, which is normally completed by day 4 of menstruation; should do biopsy on day 5+ of menstruation; biopsy shows retained secretory endometrium, fragmented menstrual endometrium, proliferative endometrium; occurs in 10% - 17% of DUB cases; associated with luteal phase defect
  • Membranous dysmenorrhea: rare, endometrial cast passed during menstruation, resembles decidua; may be due to exogenous progesterone

  • Anovulatory cycle: proliferative endometrium during chronological secretory phase; usually causes endometrial hyperplasia
Treatment
  • If other causes are ruled out, progesterone plus reassurance; optional therapy includes mid cycle estrogen (mid cycle bleeding), and late cycle progestin (late cycle bleeding), combined high dose estrogen and high dose progestin
  • Treatment goals are to stop bleeding, replace iron loss, prevent future bleeding
Microscopic (histologic) description
  • Fibrin clumps in endometrial stroma (not present in normal menstrual stroma), stromal crumbling (fragmented pieces with dense stromal cellularity)
  • Exogenous hormones cause predecidual stroma, edema and wimpy tubular glands of different sizes
  • Plasma cells are common if focal stromal breakdown is present, but this likely represents a physiologic process, not infection (Hum Pathol 2007;38:581, but see Mod Pathol 2001;14:877)
Microscopic (histologic) images

Images hosted on other servers:

Endometrial curette of perimenopausal bleeding of hormonal effect: characteristic atrophic glands and decidualized stroma