Disorders of the Menstrual Cycle

Abnormal Vaginal Bleeding د.ناديه مضر الحلي
Is a descriptive term applied to any alteration in the normal menstrual flow. The following table outlines the classical terminology applied to abnormal uterine bleeding:

Menorrhagia Prolonged & increased menstrual flow
Metrorrhagia Regular intermenstrual bleeding
Polymenorrhea Menses occurring at < 21 day interval
Menometrorrhagia Prolonged menses & intermenstrual bleeding
Oligomenorrhea Menses at intervals of > 35 days

The average menses lasts for 3-7 days with a mean blood loss of 35 ml. Menorrhagia is defined as blood loss of greater than 80 ml as women who lose this amount or more will have a lower haemoglobin & haematocrit value.
For clinical purposes, HMB should be defined as excessive menstrual blood loss which interferes
with the woman’s physical, emotional, social and material quality of life, and which can occur
alone or in combination with other symptoms. Any interventions should aim to improve quality
of life measures


Aetiology:
Abnormal uterine bleeding can be classified into :
1. Idiopathic: where no organic pathology can be found, also called dysfunctional uterine bleeding. The principal factors implicated in the pathogenesis of menorrhagia are disordered production of prostaglandinsn ( PGE2 & PGF2? ), enhanced fibrinolytic activity & abnormalities of endometrial vascular development. It is further divided into :
a. Anovulatory: this tend to occur in women at the extremes of the reproductive life & is typified by irregular cycle. It is more common in obese women.
b. Ovulatory: more common in women aged 35 to 45 years & is typified by regular heavy & often painful menstrual periods. It may be due to an inadequate production of progesterone by the corpus luteum.

2. Secondary: to organic pathology, the major organic causes of abnormal uterine bleeding include:
• Local causes :
1. Uterine fibroid : especially submucous fibroid.
2. Adenomyosis: presence of endometrial tissue embedded within the myometrium, characterized by painful heavy periods.
3. Endocervical polyp, endometrial polyp or endometrial hyperplasia: classically cause intermenstrual bleeding due to irregular shedding of the endometrium.
4. Intrauterine contraceptive device (IUCD): periods may become heavier & longer in duration. Insertion of IUCD is thought to elevate the circulating level of plasminogen activator leading to an increase in fibrinolytic activity.
5. Pelvic inflammatory disease (PID): cause erratic menstrual bleeding due to local endometrial inflammatory response, Chlamydial infection is more likely to cause intermenstrual bleeding.
6. malignancy of the cervix, uterus & ovaries : presence of postcoital bleeding should lead to the possibility of cervical lesion in particular, including cervical ectropion. Hormone producing ovarian tumors can cause endometrial hyperplasia & menstrual irregularities.
7. Trauma: can be a cause for acute presentation of abnormal vaginal bleeding.

• Systemic causes:
1. Endocrine disorders:
? Hyper or hypothyroidism.
? Diabetes mellitus.
? Adrenal disease.
? Prolactin disorders.
2. Disorders of haemostasis: mostly found in teen-agers who present with heavy bleeding. Examples are von Willebrand s disease & idiopathic thrombocytopenic purpura (ITP).
3. Liver disorders: may interfere with metabolism of estrogen.
4. renal disease : may alter the excretion of estrogen & progesterone.
5. Medication: steroid hormones, neoroleptics & anticoagula-nt.
• Pregnancy: this possibility should always be considered in women of reproductive age group. Miscarriage, ectopic pregnancy & gestational trophoblastic disease may present with abnormal bleeding.