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Possible causes

unwanted childlessness

Unwanted childlessness always affects both partners. The search for the causes must therefore always be conducted with both partners.

The reasons for unwanted childlessness are manifold and are equally distributed between men and women. In some cases there are causes of infertility in both partners, in other cases there are no discernible causes for the absence of a pregnancy. Besides organic, immunological and biological causes, psychological aspects also play a role. Environmental pollution, stress, overweight, unhealthy nutrition, excessive consumption of alcohol, coffee and drugs, and smoking can also affect fertility.

Causes of unwanted childlessness among women

Ovarian dysfunction

Functional disorders of the ovaries are usually hormonal in nature. Hormonal dysfunctions can lead to irregularities in the cycle, disorders in egg cell maturation, the absence of ovulation, and insufficient corpus luteum formation. The disturbance of the hormonal balance can be caused by any form of stress, inflammation, injury, tumours, under- or overweight, rapid, extreme weight changes, heavy physical strain, congenital malfunction of hormonal glands, medication, environmental pollutants and stimulants. Malformations of the ovaries can also be hereditary.

Infertility caused by the fallopian tubes

Fallopian tube damage can occur in many variations and is usually caused by inflammation. Inflammations can lead to closure of the ends of the fallopian tubes (fringe funnels), to adhesions of the fallopian ducts and to adhesions of the fallopian tubes. However, ectopic pregnancies and adhesions after surgery can also impair the function of the fallopian tubes. In addition, fallopian tube malformations can occur during embryonic development or be hereditary. Damage to the fallopian tubes means that the egg collection mechanism and egg transport to the uterine cavity is disturbed or completely impossible.


Endometriosis is the settling of endometrium outside the uterus. Endometriosis is probably caused by remnants of the uterine mucosa which are carried backwards through the fallopian tubes into the free abdominal cavity during menstruation. Endometriosis lesions are often found on the peritoneum, but also in the ovaries, fallopian tubes, intestines and bladder. Endometriosis can be treated with medication or surgery.

Polycystic ovary syndrome (PCO)

The PCO syndrome is based on hormonal disorders that begin as early as puberty. The degree of severity can vary greatly and ranges from a disturbed corpus luteum function to the complete absence of menstrual bleeding. Women with PCO syndrome produce more male hormouses in the ovaries and/or the adrenal cortex. This results in the formation of enlarged ovaries which carry many small follicles, with the development of the egg cells being disturbed.

Causes of unwanted childlessness in men

Testicular dysfunction

The most common disorder in men is a restricted formation of normal sperm cells that move well forward. Normally, one millilitre of seminal fluid should contain at least 20 million sperm cells, of which about one third should be of normal shape. In order to ensure that a sufficiently large number of sperm cells can make the arduous journey through the vagina, cervix and cavity and up the fallopian tubes to the egg, at least half of the sperm cells should be able to move forward. If the sperm count is below these normal values, a man's fertility is limited. Testicular dysfunction can be inherited or caused by injuries and accidents. Very often varicose veins (varicocele) are also the cause. Abnormalities in the position of the testicles in early childhood (undescended testicles) which are not recognised and corrected in time often lead to uncorrectable damage to the testicles. Semen maturation disorders can also be the late consequence of a mumps infection in childhood. Also febrile or infectious diseases sometimes temporarily restrict the sperm production of the testicles. Excessive consumption of alcohol and nicotine as well as stress and environmental pollution are further factors that can have a negative influence on sperm formation.

Disturbed sperm cell-ovum interaction

Regardless of the sperm cell density, functional disorders can also make it difficult or block the penetration of the sperm cell into the egg and thus cause infertility.

Transport disorders of the spermatic ducts

Some men produce a sufficient number of sperm cells, but there are still few or no sperm cells in their sperm because they are blocked by a blockage in the spermatic ducts. This can be caused by a blockage in the spermatic ducts or epididymal ducts, which is the result of an inflammation. Blocked or underdeveloped vas deferens can also be inherited. Injuries and operations (e.g. after inguinal hernia) can also result in a disruption in the transport of semen.