Basic Understanding of Abnormal Uterine Bleeding (AUB)

Abnormal Uterine Bleeding

Abnormal Uterine Bleeding– Any uterine bleeding outside the normal volume, duration regularity, or frequency is considered abnormal uterine bleeding. (AUB). Nearly 30 % of all Gynaecological OPD are for AUB.

Common causes of Abnormal Uterine Bleeding –

  • Dysfunctional Uterine bleeding
  • Infections
  • Endocrine Dysfunction
  • Pregnancy complication
  • Hematological Disorder
  • Neoplastic Growth



Syn – Hypermenorrhoea

Menorrhagia is defined as cyclic bleeding at normal intervals; the bleeding is either excessive amount (>80ml) or duration (>7 days) or both. The term menotaxis is often used to denote prolonged bleeding.

Causes –

Menorrhagia is a symptom of some underlying pathology –

  1. Organic
  2. Functional

1.Organic –

Pelvic – Pelvic pathology to cause menorrhagia. Due to congestion, increased surface, or hyperplasia of the endometrium.

  • Fibroid
  • Adenomyosis
  • Pelvic endometriosis
  • IUCD in utero
  • Chronic tubo-ovarian mass
  • Tubercular endometritis (early cases)
  • Retroverted uterus – Due to congestion
  • Granulosa cell tumor of the ovary

Systematic – Liver dysfunction ( cirrhosis) – Failure to conjugate and thereby inactivate the estrogens.

  • Congestive cardiac failure
  • Severe Hypertension

Endocrinal –

  • Hypothyroidism
  • Hyperthyroidism

 Haematological –

  • Idiopathic thrombocytopenic purpura
  • Leukemia
  • Von Willebrand disease
  • Platelet deficiency (Thrombocytopenia)

Emotional upset

2. Functional – Due to disturbed Hypothalamus -pituitary-ovarian-endometrial axis. Common causes of abnormal vaginal bleeding include all causes of organic, systematic, and also non-menstrual causes bleeding.

Common Causes of menorrhagia –

  • Dysfunctional uterine bleeding
  • Fibroid uterus
  • Adenomyosis
  • Chronic tubo-ovarian mass

Diagnosis –

  • Long duration of flow
  • Passage of big clots
  • Use of an increased number of thick sanitary pads
  • Pallor
  • Low level of hemoglobin

All these give an idea about the correct diagnosis and magnitude of menorrhagia.

Treatment –

 Poly menorrhea- 

Syn –Epimenorrhea

Poly menorrhea – Cyclic bleeding with an arbitrary limit of fewer than 21 days. And remains constant at the frequency. If the frequent cycle is linked with excessive and or prolonged bleeding – epimenorrhagia.

Causes –

Dysfunctional – Observed during adolescence, preceding menopause, and following delivery and abortion. Hyperstimulation of the ovary by the pituitary hormones may be the responsible factor.

Ovarian hyperemia as in pelvic inflammatory disease (PID) or ovarian endometriosis.

Treatment –


Metrorrhagia is an irregular, acyclic bleeding from the uterus .amount of bleeding is variable. At the same time, metrorrhagia strictly concerns uterine bleeding but in clinic practice, the bleeding from any part of the genital tract is included under the heading. then again, irregular bleeding in the form of contact bleeding or intermenstrual bleeding in an otherwise normal cycle is also included in metrorrhagia. In fact, it is mostly related to surface lesions in the uterus.

Menometrorrhagia is the term applied when the bleeding is so irregular and excessive that the menses cannot be identified.

Causes of Contact bleeding –

  • Carcinoma cervix
  • Mucous polyp cervix
  • Vascular ectopy of the cervix especially during pregnancy, pill use cervix.
  • Infections – chlamydial or tubercular cervicitis
  • Cervical endometritis

Causes of Acyclic bleeding –

  • DUB – usually during adolescence, following childbirth and abortion, and preceding menopause.
  • Submucous fibroid
  • Uttering polyp
  • Carcinoma cervix and endometrial carcinoma

Causes of Intermenstrual bleeding-

  • Urethral caruncle
  • Ovular bleeding
  • Breakthrough bleeding in pill use
  • IUCD in utero
  • Decubitus ulcer


Menstrual bleeding occurs more than 35 days apart and remains constant at that frequency.

Causes –

  • Age-related – During adolescence and preceding menopause
  • Weight-related – Obesity
  • Stress and exercise
  • Endocrine disorder – PCOS is the most common hyperprolactinemia and hyperthyroidism.
  • Androgen-producing tumors – ovarian, adrenal
  • Tubercular endometritis – late case
  • Drugs – Phenothiazines, cimetidine, methyldopa.


When the menstrual bleeding is unduly scanty and lasts for less than 2 days.

Causes –

  • Local – Uterine synechiae or endometrial tuberculosis.
  • Endocrinal – use of oral contraceptives, thyroid dysfunctions, and premenopausal period.
  • Systematic – Malnutrition.


A state of abnormal uterine bleeding without any clinically detectable organic, systemic, and iatrogenic causes ( With the exclusion of pelvic pathology. e.g. Tumor, inflammation, or pregnancy. )

Heavy menstrual bleeding (HMB) – bleeding that interferes with a woman’s physical, emotional, social, and maternal quality of life.

Incidence – The prevalence varies widely but an incidence of 10 % amongst new patients attending the outpatients seems logical. As the diagnosis is based on the exclusion of organic lesions .so with the care and facilities to exclude such as a lesion. the incidence varies .currently DUB is defined as a state of abnormal uterine bleeding following anovulation due to dysfunction of the Hypothalamus-pituitary -ovarian axis.

Pathophysiology –

The physiological mechanism of hemostasis in normal menstruation are :

  1. Platelet adhesion formation.
  2. Formation of platelet plug with fibrin to seal the bleeding vessels
  3. Localized vasoconstriction
  4. Regeneration of endometrium
  5. The biochemical mechanisms involved are :

In the increased endometrial ratio of PGF, 2/PGE PGF causes vasoconstriction and reduces bleeding. Progesterone increase the level of PGF from arachidonic acid .levels of endothelin, which is a powerful vasoconstrictor is also increased. In anovulatory DUB, there is decreased synthesis of PGF and the ratio of PGF /PGE is low.

Anovulatory cycles are usually not associated with dysmenorrhea as the level of PGF is low. Women with menorrhagia have a low level of thromboxane in the endometrium.

The endometrial abnormalities may be primary or secondary to incoordination in the hypothalamic-pituitary-ovarian axis. It is thus more prevalent in extremes of the reproductive period – adolescence and pre-menopause or following childbirth and abortion.

Emotional influence, worries, anxieties, or sexual problems sometimes are enough to disturb the normal hormonal balance.

The abnormal bleeding may be associated with or without ovulation and accordingly grouped into :

  1. Ovular bleeding (20%)
  2. An ovular bleeding (80%)

1. Ovular bleeding (20%)-

Poly menorrhea or polymenorrhagia: The condition usually occurs following childbirth and abortion, during adolescence and premenopausal period, and in pelvic inflammatory disease.

The follicular development is speeded up with the resulting shortening of the follicular phase. This is probably due to hyperstimulation of the follicular growth by FSH. Rarely, the luteal phase may be shortened due to premature lysis of the corpus luteum. Sometimes, it is related to stress-induced stimulation. Endometrial study prior to or within a few hours of menstruation reveals secretory changes.

Oligomenorrhea – Primary ovular oligomenorrhea is rare. It may be met in adolescence and preceding menopause.

The disturbance may be due to ovarian unresponsive to FSH or secondary to pituitary dysfunction. There is an undue prolongation of the proliferative phase with the normal secretory phase.

Endometrial study prior to or within a few hours of menstruation reveals secretory changes.

Functional Menorrhagia – Ovular menorrhagia is quite uncommon. Two varieties are found.

  • Irregular shedding and ripening of the endometrium
  • The abnormality is usually met in extremes of the reproductive period.

Normally, regeneration of the endometrium is completed by the end of the third day off, menstruation in irregular shedding, and desquamation is continued for a variable period with simultaneous failure of regeneration of endometrium. The possible explanation is –

  • Incomplete withdrawal of LH even on the 26th day of cycle -> Incomplete atrophy of the corpus luteum -> Persistent secretion of progesterone ->                                  Persistent LH -> Inhibition of FSH  -> Suppress

To Know more about AUB Consult our Gynecologist

About Author


Dr. Ankit Garg

M.S (Ayu) OBGY, Infertility Specialist

Ayu Nari infertility cure center Falana

Pin 306116 cell- +91 8302463471