Female factors :

Tubal factor
the woman's fallopian tubes are blocked or damaged, causing difficulty for the egg to be fertilized or for an embryo to travel to the uterus.

Ovulatory dysfunction
the ovaries are not producing eggs normally; such dysfunctions include polycystic ovarian syndrome (PCOS) and multiple ovarian cysts. PCOS is also referred to as PCO, or PCOD - polycystic ovarian disease. Women with PCOS and infertility usually have very irregular menstrual cycles (oligomenorrhea), and sometimes a total lack of periods, referred to in the medical world as amenorrhea.

Diminished ovarian reserve
the ability of the ovary to produce eggs is reduced; reasons include congenital, medical, or surgical causes or advanced age.

Endometriosis
involves the presence of tissue similar to the uterine lining in abnormal locations; this condition can affect both fertilization of the egg and embryo implantation.
Endometriosis causes pain in some women and can also cause infertility. 5-10% of all women have endometriosis. Most of these women are not infertile. 30-40% of infertile women have endometriosis.

Uterine factor
a structural or functional disorder of the uterus that results in reduced fertility.

Male factor :
A low sperm count or problems with sperm function or sperm production that cause difficulty for a sperm to fertilize an egg under normal conditions.
Failures of sperm productions, Genetic abnormalities,
Oxydative stress resulting from injury, infection or smoking and causing semen defects.


Other causes of infertility
immunologic problems or chromosomal abnormalities, cancer chemotherapy, or serious illnesses.

Unexplained cause
Infertility cases in which the standard infertility testing has not found a cause for the failure to conceive in either partner

Multiple factors :
Diagnosis of one or more female cause.
Multiple factors, male and female.
Diagnosis of one or more female cause and male factor infertility. (source CDC)

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