The human reproductive process is complex, but for the
purpose of evaluation, it can be divided into important basic components

  1. The Sperm must be deposited near the Cervix, at/near the time of ovulation, travel up into the fallopian tubes, and have the capacity to fertilize the egg (male factor).
  2. Ovulation of a mature oocyte (egg) must occur, ideally on a regular and predictable basis (ovarian factor).
  3. The cervix must capture, filter, nuture, and then release the sperm into the uterus and fallopian tubes (cervical factor).
  4. The uterus must be receptive to implantation/nidation of the embryo and capable of supporting its normal growth and development (uterine factor).
  5. The tubes must capture the ovulated egg and transport it and the sperm towards each other and later the embryo towards the uterus (tubal factor).

Thus basic steps important for pregnancy to happen

  • Regular ovulation
  • Normal sperms
  • Regular intercourse
  • Open and functional fallopian tubes

For pregnancy to happen all the above steps have to happen
correctly

  • Mature egg released from one of the ovary
  • Picked up by the fallopian tube, transported
    towards the uterus
  • Sperm deposited in the vagina, travels through
    cervix towards the fallopian tube, transported towards the egg
  • Fertilization happens in the tube
  • Embryo (fertilized egg and sperm) transported
    towards uterus
  • Imbeds in the endometrium, starts growing and
    thus pregnancy happens

Infertility occurs when any of the above steps is
interrupted

Ovulation disorders    20-40%

  • Pcos
  • Premature ovarian failure
  • Hyperprolactinemia
  • Hypothalamic dysfunction – due to excessive
    physical/emotional stress

Tubal and peritoneal pathology    30-40%

  • Pelvic inflammatory diseases, infection of tubes
    caused by chlamydia, gonorrhea, other sexually transmitted diseases may damage
    the fallopian tubes and block them
  • Pelvic tuberculosis
  • Previous surgery in the abdomen or pelviseg
    tubal ectopic

Uterine causes

  • Endometrial polyp
  • Intrauterine adhesions
  • Infection
  • Endometriosis
  • Adenomyosis
  • Uterine abnormalities from birth
  • Cervical stenosis

Unexplained infertility 

Male factor                                           
30-40%