Represents some 25% of all infertility cases. May be caused by several conditions such as putting or losing weight excessively, extreme physical activity, emotional stress, hormone alterations in androgen, estrogen, gonadotropin, prolactin, insulin/glucose metabolism. Alterations involving the thyroid, hair increase and galactorhea may also lead to ovulatory disorders.
Cases represent some 30-40%. Among them are injures in the fallopian tubes, endometriosis, previous gynecological surgeries, appendicitis, IUD misuse and pelvic infections especially those caused by chlamydia, ureaplasma, mycoplasma and gonococcus.
Cases represent some 5%. May be caused by tumors such as myoma and endometric polyps, congenital anomalies altering the womb anatomy thus making it difficult for the implantation process such as bi-cornuate uterus, didelphus uterus, etc., inflammatory lesions in the endometrium, adenomyosis, synechia, or adhesions resulting from uterine curettage.
Cases represent some 5 to 10%. May be caused by low production of cervical mucus, presence of immunological factors that tend to immobilize or inactivate spermatozoids, stenosis, or constriction in the cervical channel and inflammatory injures hindering the sperm migration to the uterus.
Smoking is being increasingly associated to infertility. Fecundity rate decreases directly proportional to the number of cigarettes smoked daily. Studies show that patients smoking 20 cigarettes a day exhibit a rate 20% smaller than non-smoking patients. Those smoking over 30 cigarettes exhibit rates of 57%.
Presently, with parenthood postponed to later ages due to several reasons the number of first-time mothers around 35/45 is increasing. Studies show that after 36 years old the risks of conceiving babies with cromossomic anomalies is as higher as the number of spontaneous abortions. Fertility rates decrease sharply after 40. See the tables below:
Mother Age (Years)
Spontaneous Abortion Rate (%)
Mother Age (Years)
Risk of Down Syndrome
Risk of Cromossomic Anomalies
At a report by the American Society of Reproductive Medicine showing results attained by US best clinics in 1998 in relation to IVF we may observe the following:
Mother Age (Years)
Gestation Rate (%)
In the data above we clearly see how woman age is a key factor in infertility.
Most male factors causing infertility arise basically from two situations: spermogram showing semen low quality or semen incapacity of penetrating the female genital apparatus. Many pathologies lead to sperm low production, motility alteration, viscosity, form, capacity to penetrate and speed.
Changes in the migration from testicles to the scrotum in childhood, genital anatomical injures (hypospady and epispady), parotiditis, bladder or prostate surgery, testicle cancer, use of radiotherapy or chemotherapy, toxic agents (radiation, agent orange), diabetis, genetic diseases (Klinefelter and Kallmann syndrome), hypophisary or hypothalamic injures (changes in the production of FSH, LH and prolactin); infections in the genital tract (chlamydia, ureaplasma, mycoplasma, gonococcus) may cause low spermatic potential.
Attention should be given to: the use of illicit drugs, alcohol, nicotine smoke, exposition to pesticides, medicaments (cimetidine, sulfasalazine and nitrofurantoine), frequent habit of saunas, hot baths, wearing tight jockstraps and the growing use of drugs to boost physical fitness. Patients may also be observed for: varicocele, absence of the vas deferens, and alteration in the testicular hormone production.
Nowadays, in big cities, life stress, demanding family, friends, work, and emotional distress may lead to sexual disorders that turn intercourse difficult and, consequently, gestation.