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Biochemical Aspects of Male & Female Subfertility/ Infertility. Objectives of the Lecture. Recall factors required for conception Recall the definition of infertility .
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Biochemical Aspects of Male & Female Subfertility/ Infertility
Objectives of the Lecture • Recall factors required for conception • Recall the definition of infertility. • Understand the correlation of biochemical and clinical aspects of the common endocrinal causes infertility in males and females. • Recognizing the biochemical aspects of overall laboratory investigations of infertility in males and females.
Requirements for Conception • Production of healthy ova & sperm • Unblocked tubes that allow sperm to reach the ova • The sperms ability to penetrate & fertilize the ova • Implantation of the embryo into the uterus • Finally a healthy pregnancy
Infertility/ Subfertility The inability to conceive following unprotected sexual intercourse for 1 year (age < 35) or 6 months (age >35)
Evaluation of the Infertile couple • History • Physical examination • Semen analysis (to exclude male causes) • Determination of ovulation • Basal body temperature record • Serum progesterone • Ovarian reserve testing • Endocrine investigations • Hysterosalpingogram (for uterus & tubes)
LABORATORY Diagnostic Approaches of Male InfertilitySeminal Fluid AnalysisHormonal Assay
Laboratory Seminal Fluid Analysis Normal Constituents of Seminal Fluid Seminal Vesicle Secretion Fructose: source of energy for sperms Needed for sperms motility Prostaglandins: Controlling sperm movement & sperm penetration of cervical mucus Fibrinogen-like substance : Cause of viscosity of semen (coagulation) • Prostatic Secretion • pH 6.5 (weak acidic) • Reduces acidity of vag.sec • Contains: • vesiculase • Reduces semen viscosity • Acid phosphatase • Spermine: bacteriostatic Testicular Secretion
Laboratory Seminal Fluid Analysis Physical Analysis • Volume • Liquefaction time (after coagulation) • pH Microscopic Analysis • Sperm count • Sperm morphology • Sperm motility • Sperm viability • Spermagglutination Biochemical Analysis • Fructose test • Acid phosphatase Others • Antisperm antibody
Main Causes of Male Infertility Testicular Causes: • Radiation (as X-ray, etc) • Trauma of testis • Varicocele • Orchitis (inflammation of the testis) • Systemic disorder causing low testosterone or spermatogenesis • Abnormal sperm morphology Secondary Hypogonadism: (Low GnHR, FSH , LH) • Hypothalamic causes • Pituitary causes Hyperprolactinemia Altered Sperm Transport: • Obstruction of vas deference • Congenital absence vas deferens • Vasectomy (sperm count reaches zero after 3-6 months) • Congenital absence or obstruction epidedimes • Erectile dysfunction (ED) • Retrograde ejaculation Other less common causes • As antiandrogens medications intake
Diagnostic Approach to Infertility in Males Other Anomalies Abnormal Forms Sperm Agglutin. Antobodies Pus cells RBCs Seminal Fluid Analysis Low Sperm Count Normal Sperm Analysis NORMAL Hormonal Profile No endocrine tests are required Testosterone FSH & LH Prolactin Prostate Abnormal Profile Seminal Vesicle & Ejacul. Duct Vas Deference Obstruction Vasectomy Trauma Congenital Absence Prostatic Invest. Acid Phosphatase PSA FSH & LH Testosterone Testosterone FSH & LH • Testost. • Prolactin Secondary hypogonadism Primary hypogonadism (e.g. testicular) Hyperprolactinemia Low Semen Amount Low or no Semen Coagulation Low Semen pH Low Sperm Motility & Viability Low Semen Fructose Hypothalamic or Pituitary Disease Causes ?? Orchitis, Radiation, Trauma
Primary Hypogonadism(Primary Testicular Failure) • Damage of BOTH the interstitial cells & semniferous tubules Testosterone Gonadotrophins (LH & FSH) • Damage of Onlysemniferous tubules in FSH (but LH normal) Testosterone normal (as interstitial cells intact)
VaricoceleA Cause of Male Infertility Common, disease affecting 15% of men overall & 40% of men with known infertility. Varicocele is an abnormal enlargement of the pampinform plexus of veins in the scrotum. Pampinform plexus of veins drains the testicles. Varicocele may raise the temperature the testicles or cause blood to back up in the veins supplying the testicles. Varicocele seem to help damage or kill the sperm. The detrimental effect of varicocele on sperm production is progressive and due to reduction in supply of oxygenated blood & nutrient material to the sperm production sites, which persistently reduces the quality & the quantity of the sperms, leading to reduction in their fertility capacity with time
Assessment of Sperm Morphology Normally the sperm count contains fewer than 20 % abnormal forms e.g. bitailed, short tailed , 2 heads …..etc. A Cause of Male Infertility
LABORATORY Diagnostic Approaches of Female InfertilityHormonal Assay
Common Causes Female Infertility Ovulation Disorders Causes: • Aging • Diminished ovarian reserve • Premature ovarian failure • Endocrine disorders (as PCOS) Tubal Causes: • Pelvic inflammatory disease • Tubal Surgery • Previous ectopic pregnancy • Salpingectomy Uterine/Cervical Causes: • Congenital uterine anomaly • Fibroids • Endometriosis • Poor cervical mucus quantity/quality • Infection
Diagnostic Approach to Infertility in Females Detailed History & Physical Examination Normal menses Amenorrhea, Oligomenorrhoea No Further Tests Investigations for Ovulation Progesterone n day 21 (mid luteal) Pregnancy Test + ve -ve <10 nmol/L >30 nmol/L LH, FSH & Prolactin No Ovulation Ovulation High Prolactin Low FSH & LH High FSH & LH High LH Low FSH All Normal Further Investig. Investigation for a cause of hyperprolactinemia Pituitary or hypothalam. 1ry Ovarian Failure PCOS
Endocrine causes of infertility in Females Endocrine investigation is of diagnostic value for women who have: • Irregular or no menstruation • No ovulation
Endocrine causes of infertility in women • Primary ovarian failure: oestradiol & ↑ gonadotrophins (FSH & LH) • Hyperprolactinemia (↑ blood prolactin) • Polycystic ovary syndrome (PCOS)… • Cushing’s syndrome (↑ steroid hormones) • Hypogonadotrophic hypogonadism (↓ pituitary hormones FSH & LH): rare
Cushing Syndrome • Overproduction of cortisol by the adrenal cortex mainly caused by adrenal cortical adenoma • Due to increased production of adrenal cortical androgens (androstendione)
Hyperprolactinemia Prolactin Hormone secreted by the anterior pituitary It acts directly on the mammary glands to control lactation Hyperprolactinaemia • Elevated blood prolactin • A common cause of infertility in both sexes due to gonadal function impairment • Early indication of hyperprolactinemia: amenorrhea & galctorrhoea
Hyperprolactinemia Increased prolactin hormone secretion by the anterior pituitary gland. Common causes of hyperprolactinemia • Stress • Medications e.g. estrogens intake • Primaryhypothyroidism :prolactin is stimulated by TRH • Pituitary disease • Prolactinoma: microadenoma of the pituitary cells secreting prolactin • Idiopathichypersecretion: e.g. due to impaired secretion of dopamine that usually inhibits prolactin release
Hyperprolactinemia Diagnosis of the cause of hyperprolactinemia: • FFIRST, the followings causes should be EXCLUDED: • Stress • Medications intake • Primary hypothyroidism (low T3 & T4, High TSH) • Pituitary diseases (assay of other pituitary hormones) If all above are excluded • Differential diagnosis between: • Prolactinoma • Idiopathic hypersecretion: • Detailed pituitary MRI (to exclude prolactinoma) • Dynamic tests of prolactin secretion: 1- Administration of TRH. 2- Then, blood prolactin (PRL) is measured: • if PRL : Idiopathic hyperprolactinemia (caused by low dopamine) • If no in PRL: Pituitary tumor
Polycystic Ovary Syndrome (POCS) Polycystic ovary syndrome is a problem in which a woman’s hormone are out of balance. It can cause irregular menstruation & may lead to infertility (due to anovulation). Polycystic ovary syndrome (or PCOS) is common, affecting as many as 1 out of 15 women. Often the symptoms begin in the teen years. For reasons that are not well understood, in PCOS the hormones get out of balance. One hormone change triggers another, which changes another. For example, the sex hormones get out of balance. Normally, the ovaries make a tiny amount of male sex hormones (androgens). In PCOS, ovaries produce more androgens. & thus this may cause anovulation, menstrual disturbances, infertility, acne & grow extra facial & body hair (hirsutism)
FSH LH LH receptor cholesterol Androstendione Estradiol aromatase AndrostendioneTestosterone Theca cell Granulosa cell of ovary Review of Synthesis of Steroid Hormones(testosterone & estradiol) in the Ovary FSH receptors
Polycystic Ovarian Syndrome (POCS) ↑ LH (with N. or ↓ FSH) Stimulation of theca cells of the ovary by LH to produce androstendione Which is converted to testosterone in granulosa cells Anovulation Hirsutism ↑ Estradiol in granulosa cells ↑Free testosterone Start here ↓ SHBG Biochemical, Endocrinal & Clinical Changes in PCOS Obesity Insulin resistance
Polycystic Ovarian Syndrome (POCS) • The common clinical features of PCOS are: - Menstrual irregularities - Signs of androgen excess (as hirsutism) - Subfertility/Infertility (due to anovulation) - Insulin resistance (due to obesity) • The classical hormonal profile of PCOS is: - Hypersecretion of LH(in 60% of cases) - Androgen (testosterone) excess - Normal (or low) concentration of FSH • It is important to exclude disorders with similar presenting features as androgen secreting tumors & CAH
Polycystic Ovarian Syndrome (POCS) • Laboratory Investigations of POCS • ↓SHBG (sex hormone binding globulin) • ↑Free Testosterone (&↓ Total testosterone ) • ↑Androgens (androstendione) • ↑LH: in 60% of cases • Normal (or low) FSH • ↑ LH/FSH ratio : in > 90% of patients
Polycystic Ovary Syndrome (POCS) Ultrasonographic (Sonar) Diagnosis of POCS
Polycystic Ovary Syndrome (POCS) Biochemical Aspects of Treatment of POCS Is directed towards interrupting the cycle by • Lowering LH levels with oral contraceptive pills • Increasing FSH production by clomiphen • Weight reduction in obese patients (to reduce insulin resistance)