Menstrual Cycle Dr. Hazrat Bilal Malakandi DPT (IPM&R KMU)

Menstrual Cycle Rhythmic cyclic changes in mucous membrane (endometrium) of uterus, associated with cyclic production of estrogen and progesterone is called menstrual cycle Period – 28 days (20-45 days)

Significance These cyclic changes in uterus are for preparation of uterus for implantation and nutrition of the embryo and for pregnancy. But when fertilization fails to occur, uterine epithelium sheds off and blood vessels necrosis occurs as a result which blood and mucus along with degenerated epithelium oozes out through vagina, each month in a cyclic fashion

Phases Three phases Menstruation phase Proliferative phase – (also called postmenstrual or estrogen phase) Secretary phase – (also called premenstrual or progesterone phase)

Menstruation phase – During this phase all superficial layers of endometrium are desquamated through vagina

Proliferative phase – Estrogen in first ½ of ovarian cycle causes rapid proliferation of stromal and epithelial cells – Endometrium (that was desquamated during menstruation) is thus reepithilialized within 3-7 days – Endometrium increase in thickness (3-5 mm) due to increase no. of stromal cells and endometrial glands and blood vessels

Hormonal Fluctuation After bleeding is over or during last days of menstruation, hypothalamus releases follicle releasing hormone (FRH) which stimulate ant. Pituitary gland to secrete FSH. This in turn causes excessive growth of follicles. The follicle estrogen, which is responsible for the proliferation of endometrium and makes it thicker. Just before (2-3 days) ovulation, LH appears which causes ovulation and formation of corpus luteum. This corpus luteum secretes progesterone.

Secretary phase – Progesterone in last ½ of ovarian cycle causes marked swelling and secretary development of endometrium – Glands become tortous – Secretary substance accumulate in glandular epithelium – Cytoplasm, lipid and glycogen increase in stromal cells – Blood vessels increase and become tortuous – Endometrium increase in thickness (5-6 mm)

Causes of menstruation – Cessation of estrogen and progesterone secretion two days before menstruation

Menstrual fluid – Volume = 70 ml Characteristic – Does not clot due to presence of fibrinolysin

Preovulatry LH surge One or two days prior to ovulation, LH secretion increase due to positive feedback effect of estrogen, this is called preovulatry LH surge. Importance – Preovulatry LH surge is essential for ovulation to occur

Anovulatory Cycles Female sexual cycles in which ovulation does not occur are called anovulatory cycles. Causes by – Insufficient preovulatry LH surge. Anovulatory cycles occur: – Few cycles after puberty – Several cycles before menopause Menarche – Onset of menstruation is called menarche.

Menopause Cessation of menstruation in old age is called menopause. Caused by – Cessation of female sex hormones secretion Age : years Symptoms – Hot flushes – Psychic sensation of dyspnea – Irritability – Fatigue – Anxiety

Amenorrhea Cessation of menstruation at any age is called amenorrhea. Two types A.False Amenorrhea B.True Amenorrhea A. False Amenorrhea – (also called hidden menstruation or crypto menorrhea) – In this menstruation takes place but patient is unaware of it because outflow of menstrual fluid is blocked at level of cervix, vagina or vulva.

B. True amenorrhea – In this menstrual function is suppressed so that there is no menstrual fluid. Two subtypes 1.Physiological 2.pathological a.Primary b.secondary

1. Physiological – Before puberty – During pregnancy – During lactation – After menopause

2. Pathological – Amenorrhea is a clinical symptom not a disease and has a variety of causes. This can be divided into: a. Primary – It means failure of menstruation to occur at puberty – Types Hypothalamic amenorrhea Pituitary amenorrhea Ovarian amenorrhea Uterine amenorrhea

Hypothalamic amenorrhea – Failure of hypothalamus to secrete LHRH Pituitary amenorrhea – Failure of anterior pituitary gland to secrete LH and FSH. Ovarian amenorrhea – Failure of ovaries to secrete estrogen and progesterone Uterine amenorrhea – Absence of disease of uterus

b. Secondary – It means cessation of menstruation after it has once occurred at puppetry. Causes – Endocrinal disease – Chronic diseases – Malabsorption syndromes

Endocrinal disease – Hypo or hyperthyroidism – Diabetes mellitus – Cushing’s syndrome Chronic diseases – Pulmonary tuberculosis – Lymphoma – Crohn’s disease Malabsorption diseases – Starvation – Anorexia nervosa – anemia

Dysmenorrhea – Painful menstruation is called dysmenorrhea – May be due to psychology – Enzyme fibrinolysin is absent so dry clots appears, causing pain. Polymenorrhea – Abnormal frequent menstruation is called polymenorrhea – Bleeding continues for more than 6 days.