week 5

• Subfertility


  Exists when a pregnancy has not occurred after at least 1 year of engaging in unprotected coitus
• Primary subfertility


  There have been no previous conceptions
• Secondary subfertility


  There has been a previous viable pregnancy but the couple is unable to conceive at present
• Sterility


  The inability to conceive because of a known condition, such as the absence of a uterus
• In about 40% of couples with a subfertility problem, cause of subfertility is multifactorial
• Causes of subfertility


  • 30% of couples - man who is subfertile
  • 20 % to 25% - experience ovulatory failure
  • 20% experience tubal, vaginal, cervical, or uterine problems
  • 10% - no known cause despite all the diagnostic tests currently available categorized as having unexplained subfertility
• When engaging in coitus an average of 4x per wk. 50% of couples will conceive within 6 months, and 85% within 12 months
• These periods will be longer if sexual relations are less frequent
• Couples who engage in coitus daily may have more difficulty conceiving than those who space coitus to every other day
• Too-frequent coitus can lower a man's sperm count to a level below optimal fertility

  
• Subfertility increases with age, and women who defer pregnancy to their late 30s are apt to have more difficulty conceiving
• Using oral, injectable, implanted hormones for contraception may have difficulty becoming pregnant for several months after discontinuing these medications
• It takes that long for the body to restore normal functioning
• Male subfertility factors


  • Disturbance in spermatogenesis
  • Obstruction in the seminiferous tubules, ducts, or vessels preventing movement of spermatozoa
  • Qualitative or quantitative changes in the seminal fluid preventing sperm motility
  • Development of autoimmunity that immobilizes sperm
  • Problems in ejaculation or deposition preventing spermatozoa from being placed close enough to a woman's cervix to allow ready penetration and fertilization
• Sperm count


  The number of sperm in a single ejaculation or in a milliliter of semen

  
• Minimum sperm count considered normal is 20 million/ml of seminal fluid, or 50 million per ejaculation

  
• At least 50% of sperm should be motile, and 30% should be normal in shape and form

  
• Spermatozoa must be produced and maintained at a temperature slightly lower than body temperature to be fully motile
• Conditions that significantly increase body temperature

  • Chronic infection from tuberculosis
  • Recurrent sinusitis
• Actions that increase scrotal heat

  • Working at desk jobs
  • Driving everyday may produce lower sperm counts
  • Frequent use of hot tubs or saunas may lower sperm counts
• Cryptorchidism


  Undescended testes
• Cryptorchidism may lead to lowered sperm production if surgical repair was not completed until after puberty or if the spermatic cord became twisted after the surgery
• Varicocele


  Varicosity of the spermatic vein
• Varicocele could increase temperature within the testes slow and disrupt spermatogenesis
• Surgery to repair the varicocele has the potential to increase the chance for conception
• Causes of trauma to the testes

  • Surgery on or near the testes that results in impaired testicular circulation
  • Endocrine imbalances of the thyroid, pancreas, or pituitary glands
• Other causes of inadequate sperm count

  • Drug use
  • Excessive alcohol use
  • Exposure to x-ray or radioactive substances
• When undergoing pelvic radiography, men and boys are always furnished with a protective lead testes shield
• Diseases that can result in obstruction or impaired sperm motility

  • Mumps orchitis
  • Epididymitis
  • Tubal infections (gonorrhea or ascending urethral infection)
• Benign hypertrophy of the prostate gland


  Pressure from the enlarged gland on the vas deferens can interfere with sperm transport
• Infection of the prostate, seminal vesicles can change the composition of the seminal fluid enough to reduce sperm motility
• Anomalies of the penis


  • Hypospadias (urethral opening on the ventral surface of the penis)
  • Epispadias (urethral opening on the dorsal surface)
• Anomalies of the penis can cause sperm to be deposited too far from the sexual partner's cervix to allow optimal cervical penetration
• Extreme obesity in a male may also interfere with effective penetration and deposition
• Causes of ejaculation problems

  • Psychological problems
  • Diseases such as cerebrovascular accident, diabetes, or Parkinson's disease
  • Medications (Antihypertensive agents)
• Erectile dysfunction


  Impotence or the inability to achieve an erection
• Erectile dysfunction can be a difficult problem to solve if it is associated with stress
• Solutions for erectile dysfunction include psychological or sexual counseling and use of a drug sildenafil
• Premature ejaculation


  Ejaculation before penetration
• Causes of premature ejaculation

  • Psychological causes
  • Adolescents may experience it until they become more experienced in sexual techniques