infertility
Table of Contents
infertility
introduction
- defined as the inability for a couple to concieve within 1 year of unprotected intercourse
- 15% of couples meet this criterion
- 35% of these are due to female factors alone, 30% due to male factors alone, 20% due to combined male and female factors, and 15% are unexplained
- 70% of conditions that cause infertility in men can be diagnosed with history, physical examination, and hormonal and semen analysis alone
- < 3% of cases of male infertility are due primarily to a hormonal cause
causes of female infertility
- anovulation
- see amenorrhoea
- tubal disease
- PH ectopic pregnancy or other tubal surgery
- peritoneal adhesions secondary to previous pelvic surgery, endometriosis, and ovarian cyst rupture
- primary ovarian failure
- uterine malformations
- uterine pathologies:
- Asherman syndrome
- endometritis
- HHV-6A may account for 40% of unexplained infertility and 10% of all female infertility 1)
- cervical stenosis
- abnormalities of the mucus-sperm interaction
- advancing age
causes of male infertility
- check timing of coitus is appropriate
- ask past history:
- undescended testes (cryptorchidism), testicular cancer, torsion or trauma, postpubertal mumps, developmental delay, and precocious puberty, urinary tract infections (UTIs) / cystitis, sexually transmitted infections (STDs/STIs), bladder neck surgery or inguinal hernia repair
- prenatal exposure to DES
- chemotherapy
- radiotherapy / radiation
- < 1Gy - complete recovery seems possible after 18 months
- 2-3Gy results in damage to spermatocytes but recovery may occur by 5yrs
- 4-6Gy results in damage to spermatids and recovery may occur by 5yrs however permanent infertility is a risk over 3 Gy 2)
- diabetes - multiple mechanisms
- obesity
- sickle cell disease may have caused ischaemia of testes
- haemosiderosis from multiple blood transfusions
- haemochromatosis
- tuberculosis (TB) of vas or epididymis
- leprosy
- epididymo-orchitis
- chronic illness
- stress, acute febrile illnesses, and other illnesses and drugs may suppress gonadotrophin release resulting in decreased sperm production of the subsequent 1-3 months
- very high levels of exercise
- seminal cytokines and reactive oxygen species increased during aerobic and non-aerobic isometric exercise
- in professional athletes like soccer and rugby players, neutrophils and superoxide dismutase (SOD) levels were elevated after a match and the season.
- semen impairment is observed in mountaineers with higher altitudes (> 2000 m), along with the risk of hypoxia
- excessive scrotal temperatures:
- 40% decline in sperm concentration for every 1 °C rise in scrotal temperature
- heat exposure such as saunas or spas may reduce sperm production in short term
- sedentary work conditions elevate scrotal temperature by an average of 0.7 °C and up to 2.2 °C in car drivers 3)
- infertility rate in Saudi Arabian bakers exposed to a wet-bulb globe temperature (WBGT) of 37 °C was 22.7% compared to 3% in healthy volunteers
- in steel industry workers exposed to a WBGT of 36 °C, sperm parameters such as morphology, count, motility, and semen volume significantly differed from those unexposed
- occupational chemical exposures
- family history of genetic disorders such as:
- Young's disease - recurrent pulmonary infections and azoospermia due to inspissated material in the epididymis causing obstruction
- cystic fibrosis
- look for:
- testicular size
- normal epididymus, vas deferens and spermatic cord
- short anogenital distance (<52mm) is associated with 7x risk of subfertility 4)
- babies with high total antenatal exposure to phthalates were 90x more likely to have a short AGD
- varicocoele
- the most common correctable cause of infertility (30-35%) and the most common cause of secondary (acquired) infertility (75-85%)
- hypospadius (may result in not being able to place semen at cervical os)
- prostate masses
- lymphoma
- signs of endocrine diseases:
- gynaecomastia or liver disease
- Cushing's syndrome
- pituitary prolactinomas affecting visual fields
- signs of genetic disorders:
- Klinefelter syndrome -
- Noonan's syndrome - webbed neck, short stature, low-set ears, ptosis, etc.
- Down's syndrome
- Myotonic dystrophy
- Kallmann syndrome - midline defects such as anosmia, cleft lip and cleft palate, deafness, cryptorchidism, and color blindness
- Prader-Willi syndrome - obesity, mental retardation, small hands and feet, and hypogonadotropic hypogonadism
- Laurence-Moon-Biedl syndrome - retinitis pigmentosa and polydactyly
- bronchiectasis - immotile cilia syndrome or Young's disease
- small semen volume (< 1.5ml):
- retrograde ejaculation which may be caused by:
- diabetic neuropathy
- bladder neck surgery
- RPLND
- transurethral prostatectomy
- colon or rectal surgery
- multiple sclerosis
- spinal cord injury
- alpha-antagonists
- absence of the vas deferens or seminal vesicles
- ductal obstruction
- hypogonadotropism
- poor sympathetic response
- deficiencies in sperm formation
- < 40% sperm with normal movement
- pyospermia
- antisperm antibodies
- varicocele
- sperm ultrastructural abnormalities
- partial ductal obstruction
- < 30% sperm with normal morphology (teratospermia):
- excessive exposure to heat or radiation
- infectious processes
- oligospermia (< 20 million sperm per mL):
- azoospermia
- more likely to have a chromosomal abnormality (10-15%) than infertile men with sperm density within the reference range (1%)
- ejaculatory duct obstruction
- hypogonadotropism
- Young's syndrome - obstructive azospermia with chronic suppurative lung conditions
- cystic fibrosis - absence of vas deferens
- NB. a study published Jan 2024 suggests semen microbiome can also adversely affect male fertility - particularly Lactobacillus iners and Pseudomonas stutzeri 5)
infertility.txt · Last modified: 2026/04/01 00:32 by gary1