MENSTRUATION AND MENSTRUAL DISORDERS

Asomma Kubire

Objectives

• Understand hormonal changes in menstrual cycle

• Understand ovarian changes in menstrual cycle

• Understand endometrial changes in menstrual cycle

• Identify, diagnose and treat some abnormalities of menstruation

Stages of menstrual cycle

• Follicular phase (Proliferative phase)

• Luteal phase (Secretory phase)

• Cycle ranges between 25 and 32 days

• Menstrual flow is for 4-6 days

• Luteal phase lasts between 12 and 16 days

• Luteal phase is usually reported to be of constant duration – 14 days

Organs involved in menstrual cycle

• Hypothalamus

• Anterior pituitary

• Ovary

• Uterus (Endometrium)

Hormones in menstrual cycle

• Gonadotrophin Releasing Hormone (GnRH)

• Follicle Stimulating Hormone (FSH)

• Luteinising Hormone (LH)

• Estrogen

• Progesterone

Pituitary and Hypothalamic events

• Atrophy of the corpus luteum with falling progesterone and estrogen levels initiates the menstrual cycle

• Low estrogen and progesterone levels cause GnRH secretion by the hypothalamus

• GnRH acts on the pituitary to secrete FSH and LH• FSH initiates development of the follicles in the

ovary

Ovarian events

• FSH causes development of 18-20 follicles• Developing follicles produce estrogen through

action of FSH and LH• One follicle becomes dominant follicle• Rising estrogen levels inhibit FSH and LH• All follicles except dominant follicle undergo

atresia• Rising estrogen levels from dominant follicle

cause LH surge• LH surge brings about ovulation

Post ovulatory events

• Corpus luteum (CL) is formed after ovulation

• CL produces progesterone and estrogen• Hormones from CL maintain endometrium

until CL undergoes atresia• Atresia of CL leads to shedding of

endometrium – menses- and initiation of another cycle

Hormonal Events

• Negative feedback

• Positive feedback

• LH surge starts 34-36 hours before ovulation

• Peak of LH surge is 10-12 hours before ovulation

Ovarian Events

• Stages of follicle development – primordial, primary, secondary, tertiary, graafian

• Recruitment of follicles

• Emergence of dominant follicle

• Ovulation

• Corpus luteum formation

Endometrial Events

• Changes are due to estrogen and progesterone

• Proliferative phase is characterised by increase in growth of endometrium – primarily glandular growth

• Glands are narrow and tubular with mitoses and pseudostratification

Endometrial events

• Luteal phase changes are used to date the the cycle

• Day 16 – pseudostratification and subnuclear vacuoles: first sign of ovulation

• Day 17 – glands are tortuous and dilated• Day 18 –vacuoles are beside nuclei• Day 19 – pseudostratiication and vacuoles

have disappeared

Endometrial events

• Day 21,22 – edematous endometrial stroma• Day 23 – stromal mitosis starts• Day 24 – predecidual cells surrounded by spiral

arterioles and numerous stromal mitoses• Day 25 – predecidual cells begin to differentiate

under surface epithelium• Day27 – upper portion of endometrial stroma

made up of well-diffrentiated decidua-like cells

Menstrual disorders

• Dysmenorrhea

• Menorrhagia

• Amenorrhea

Menstrual disorders

• Dysmenorrhea: Painful lower abdominal cramps occurring just before or during the menses

• Primary dysmenorrhea begins at or shortly after menarche

• Secondary dysmenorrhea occurs well after menarche and is associated with pelvic pathology

Menstrual disorders

• Primary dysmenorrhea is due to abnormalities of prostaglandin metabolism

• Secondary dysmenorrhea – pelvic infection, uterine fibroids, endometriosis, adenomyosis

Treatment of dysmenorrhea

• Primary: NSAIDS and oral contraceptives

• Secondary: Treatment of underlying cause

Menstrual disorders

• Menorrhagia is prolonged (more than 7 days) or excessive (over 80ml) uterine bleeding occrring at regular intervals

• Dysfunctional uterine bleeding: Excessive uterine bleeding with no demonstrable organic cause

Menstrual disorders

• DUB is due to abnormalities of prostaglandin metabolism

• Menorrhagia – gynaecolgical causes, endocrine causes, haematologic causes

Causes of menorrhagia

• Uterine fibroids

• Adenomyosis

• Endometrial CA

• Hypothyroidism

• Bleeding disorders

Menstrual disorders

• Amenorrhea: absence of menses during the reproductive years

• Primary amenorrhea: Absence of spontaneous menses in an individual older than 16

• Secondary amenorrhea: absence of menses in an individual who has previously had spontaneous menstrual periods

Causes of secondary amenorrhea

• Pregnancy

• Anovulation

• PCOS

• Intrauterine synechiae

• Secondary Vaginal atresia

• Hyperprolactinaemia

• Pituitary tumours

• Cushing’s syndrome

• Hyperthyroidism

• Premature ovarian failure

• Hypothalamic pituitary dysfunction

• Stress

• Severe weight loss

• General medical disorders

• Adrenal tumours

Causes of primary amenorrhea

• Turner’s syndrome

• CNS tumours

• Androgen insensitivity (Testicular feminisation syndrome)

• Hyperprolactinaemia

• Congenital adrenal hyperplasia

• Vaginal atresia

• Imperforate hymen

• Mullerian abnormalities

• Hyperthyroidism

• Late development

• Stress

• Low body weight

• Adrenal tumours

Investigation of secondary amenorrhea

• History and examination• Pregnancy test• Progesterone challenge• FSH, LH assay• Serum prolactin• Thyroid function tests• CT scan / lateral skull X-ray• Hysterosalpingogram• USG

Investigation of primary amenorrhea

• History• Examination• Chromosomal studies• FSH, LH assay• Serum prolactin• CT scan• USG• Laparoscopy