*DYSMENORRHOEA*

Dysmenorrhoea literally means painful menstruation.But a more realistic and practical definition includes cases of painful menstruation of sufficient magnitude so as to incapacitate day -to-day activities.

◼️The primary dysmenorrhoea is one where there is no identifiable pelvic pathology.

▪️Incidence:The incidence of primary dysmenorrhoea of sufficient magnitude with incapacitation is about 15-20percent.With the advent of oral contraceptives and non-steroidal anti-inflammatory drugs,there is marked relief of the symptoms.

▪️Cause of pain:The mechanism of initiation of uterine pain in primary dysmenorrhoea is difficult to establish.But the following are too often related.

▪️ Mostly confined to adolescents.

▪️ Almost always confined to ovulatory cycles.

▪️The pain is usually cured following pregnancy and vaginal delivery.

▪️The pain is related to dysrhythmic uterine contractions and uterine hypoxia.

Uterine myometrial hyperactivity has been observed in cases with primary dysmenorrhoea .

The outer myometrium and the subendometrial myometrium are found to be different structurally and functionally.The subendometrial layer of myometrium is known as Junctional zone(JZ).There is marked hyperperistalsis of the JZ in women with endometriosis and adenomyosis.In women with dysmenorrhoea significant changes in JZ are seen.These include irregular thickening and hyperplasia of smooth muscle and less vascularity.This is known as Junctional zone hyperplasia.Dysperistalsis and hyperactivity of the uterine JZ are the important mechanisms of primary dysmenorrhoea .

🔹Role of vasopressin-

There is increased vasopressin release during menstruation in women with primary dysmenorrhoea .This explains the persistence of pain in cases even treated with antiprosta glandin drugs.The mechanism of action is yet to be explored.Vasopressin increases myometrial activity directly.It causes uterine hyperactivity and dysrhythmic contractions->ischaemia and hypoxia->pain.

🔹Endothelins causes myometrial smooth muscle contractions, specially in the endomyometrial junction (JZ).Local myometrial ischaemia caused by endothelins and PGF2α aggravate uterine dysperistalsis and hyperactivity.

🔹 Platelets activating factor (PAF) is also associated with the aetiology of dysmenorrhoea as it's concentration is found high.Leukotrienes and PAFs are vasoconstrictors and stimulater myometrial contractions.

🔹 Clinical features:

The pain begins a few hours before or just with the onset of menstruation.The severity of pain usually lasts for few hours,may extend to 24hours but seldom persists beyond 48hours.The pain is spasmodic and confined to lower abdomen;may radiate to the back and medial aspect of thighs.Systemic discomforts like nausea, vomiting, fatigue, diarrhoea, headache and tachycardia may be associated.It may be accompanied by vasometer changes causing pallor,cold sweats and occasional fainting.Rarely,syncope and collapse in severe cases maybe associated.

Abdominal or pelvic examination doesn't reveal any abnormal findings.

For detection of any pelvic abnormalities,ultra sound is very useful and it is not invasive.

◼️ Secondary Dysmenorrhoea (Congestive)

Secondary dysmenorrhoea is normally considered to be menstruation -associated pain occuring in the presence

of pelvic pathology.

🔸 Cause of pain:

The pain maybe related to increasing tension in the pelvic tissues due to pre-menstrual pelvic congestion or increased vascularity in the pelvic organs.

🔸Common causes of secondary dysmenorrhoea :

Cervical stenosis,chronic pelvic infection, pelvic endometriosis, pelvic adhesions,adenomyosis,uterine fibroid, endometrial polyp,IUCD in utero and pelvic congestion.Obstruction due to mullerian malformations are the other causes.

🔸Right ovarian vein syndrome:

Right ovarian vein crosses the ureter at right angle.During pre-menstrual periods,due to pelvic congestion or increased blood flow,there maybe marked engorgement in the vein->pressure on ureter->stasis->infection ->pyelonephritis->pain.