PRIMARY AMENORRHOEA

AMENORRHOEA IS DEFINED AS THE ABSENCE OF MENSTRUATION FOR MORE THAN 6 MONTHS IN

THE ABSENCE OF PREGNANCY IN A WOMAN OF FERTILE AGE,

PRIMARY AMENORRHOEA IS WHEN GIRLS FAIL TO MENSTRUATE BY 16 YEARS OF AGE.

THE ETIOLOGY:

• HYPOGONADOTROPIC HYPOGONADISM,

• HYPERGONADOTROPHIC HYPOGONADISM.

HYPOTHALAMIC DISORDERSHypothalamic disorders will give rise to hypogonadotropic hypogonadism, with the following causes:• Excessive exercise, weight loss, and stress.• Hypothalamic lesions (craniopharyngioma, glioma), which can compress hypothalamic tissue or blockdopamine.• Head injuries.• Kallman’s syndrome (X-linked recessive condition. The defect is in the area of the brain that produces GnRH, but it’s also close to the olfactory center. CNS imaging will rule out a brain tumor.• Systemic disorders including sarcoidosis, tuberculosis resultsng in an infiltrative process in thehypothalamo-hypophyseal region.• Drugs: progestogens, HRT or dopamine antagonists.

PITUITARY DISORDERSPituitary disorders will also give rise to hypogonadotrophic hypogonadism, with the following causes:• Adenomas, of which prolactinoma is most common.• Pituitary necrosis (e.g. Sheehan’s syndrome, due to prolonged hypotension following major obstetric haemorrhage).• Iatrogenic damage (surgery or radiotherapy).• Congenital failure of pituitary development.

OVARIAN DISORDERSAn-ovulation is often due to polycystic ovary syndrome (PCOS).Ovarian failure is the cause of hypergonadotrophic hypogonadism. Premature ovarian failure (POF) is defined as:cessation of periods before 40 years of age.

ENDOMETRIAL DISORDERS

Primary amenorrhoea may result from Müllerian defects

in the genital tract including an absent uterus.(Müllerian

agenesis, also known as Mayer–Rokitansky–Küster–

Hauser syndrome (MRKH) ) or

outflow tract abnormalities, leading to a haematocolpos.

CHROMOSOMAL CAUSESGonadal dysgenesis: Turner’s syndrome

• Chromosome pattern XO

• Present with primary amenorrhoea for there are either no ovaries or

non-functioningg streaks of

tissue with no oogenesis.

• The vagina and uterus are present.

• Poor breast development.

• Little or no axillary and pubic hair.

• Short stature.

• Webbing of the neck.

• A wide carrying angle in the arms.

• Coarctation of the aorta.

• Congenital malformation of the kidneys may be

found.

CHROMOSOMAL CAUSESAndrogen insensitivity syndrome (AIS)

• Chromosomal pattern XY.

• Due to lack of androgen receptors (deletion on X

chromosome). Without androgen stimulation, internal Wolffian duct structures atrophy.

With testicular Müllerian inhibitory factor present, the Müllerian duct derivatives

involute.

• Active breast development (hepatic oestrogens).

• Absent or scanty axillary and pubic hair.

• Usually absent uterus with a very short vagina.

• Primary amenorrhea

• (+) breasts and uterus

• Normal height and weight

What’s Your Differential?!!

Primary amenorrhea

• (+) breasts but (–) uterus

• (+) pubic and axillary hair

?=

Primary amenorrhea

• (+) breasts but (–) uterus

• (–) pubic and axillary hair

=?

• Primary amenorrhea

• (–) breasts but (+) uterus

• ↑ FSH levels

• Primary amenorrhea

• (–) breasts but (+) uterus

• ↓ FSH levels

Primary amenorrhea

• (–) breasts but (+) uterus

• Anosmia

History:

Investigation of amenorrhoea

#pregnancy test should be carried out if the patient is sexually active.# Blood can be taken for LH, FSH and testosterone; raised LH or raised testosterone could be suggestive of PCOS; raised FSH may be suggestive of POF. #A raised prolactin level may indicate a prolactinoma#Thyroid function#An ultrasound scan can be useful in detecting the classical appearances ofpolycystic ovaries#(MRI) of the brain should be carried out if symptoms are consistent with a pituitary adenoma.

Hysteroscopy is not routine, but is a suitableinvestigation where Asherman or cervical stenosis is suspected.Karyotyping is diagnostic of Turner’sand other sex chromosome abnormalities

ManagementHypothalamic–pituitary failure ,Gonadal

dysgenesis :treated with estrogen and

progesterone

replacement for development of the

secondary sexual characteristics.

Androgen insensitivity:: testes removal at

age 20 because the higher temperatures

associated with the intraabdominal position

of the testes may lead to testicular cancer.

Estrogen replacement is then needed.

Müllerian agenesis:surgical elongation of

the vagina

LET’S DO SOME QUESTIONS:

Question 1

A mother is concerned for her 16-year-old daughter. The daughter appears to have appropriate secondary sexual development for her age but has never menstruated. Which diagnosis matches the daughter's symptoms most appropriately?-oligomenorrhea -Primary amenorrhea -secondary amenorrhea -Gonadal dysgenesis

Question 2

True or False:

FSH and LH levels can help you determine the difference

between hypothalamic amenorrhea and pituitary

amenorrhea.

Question 3

A female senior in high school complains that she

never developed like the rest of her friends. Her

breasts never developed and she still hasn't

experienced menarche. During your review of

systems, you discover that she lacks a sense of

smell. What is your primary diagnosis?