Fertility problems

By (embryologist) and (fertility counselor).
Last Update: 09/01/2015

A couple might have a fertility problem when, after one year (or six months if the woman is older than 35) of regular, unprotected sexual intercourse, pregnancy is not achieved.

Nowadays, fertility problems in Spain affect 2 in every 10 couples of reproductive age, and this number keeps on increasing. However, thanks to technological advances, 90% of couples with fertility problems are successfully treated and their dream of being parents becomes true.

Fertility problems can be due to male, female, or mixed causes. There are also cases of unknown causes.

Provided below is an index with the 5 points we are going to expand on in this article.

Male fertility problems

The main cause of male infertility is bad sperm quality. It can be due to several factors, such as low sperm quantity (oligospermia), zero sperm concentration (azoospermia), or affected mobility (asthenospermia) or morphology (teratozoospermia). There are also other parameters like low sperm volume, yellow or pinkish sperm, sperm with a strong and unpleasant smell, thick or watery ejaculate...

This will decrease the likelihood of the spermatozoid fertilizing the egg. A temperature rise in the area, greater stress, smoking, excessive alcohol consumption, environmental pollution, nutritional deficiencies, impotence or excessive sexual activity, and endocrine or infectious problems can also affect the sperm.

Other less common causes are the following:

  • Erectile dysfunction: it can happen due to physical or psychological reasons.
  • Varicocele: infection in which the veins of the spermatic cord are larger than normal.
  • DNA fragmentation problems: when sperm DNA is altered or damaged, and if the egg is fertilized, the embryo may have problems developing or stop evolving, which would cause an abortion.
  • Vitamin deficiency: vitamin A stimulates the production of male sexual hormones, vitamin B12 and folic acid improve morphology, vitamin C reduces chromosomal errors and, according to some studies, a vitamin E deficiency favours sterility.

Female fertility problems

The incorporation of women into the professional world and the pace of modern life are the main reasons why women delay motherhood. Thus, women decide to become mothers at a biologically advanced age since egg quantity and quality sharply decrease after the woman is 37-40.

In women, most fertility problems are caused by ovulation problems, blockages of the fallopian tube or endometriosis, which we will explain hereunder.

Such problems usually occur when a woman's hormone levels are altered. This can affect ovulation and prevent the release of a mature egg. A characteristical sign of ovulation problems consist of irregular periods. Factors such as stress, emotional problems, and diseases can alter ovulation. One of its most frequent causes is the polycystic ovary syndrome.

Fallopian tube problems

A fallopian tube obstruction can prevent the sperm from reaching the egg and can make the egg move into the uterus, hindering the meeting between the two gametes. The most common cause is an infection due to Chlamydia since it presents no symptoms and many women don't know they have it.


Endometriosis happens when endometrial tissue grows outside the uterus and is characterized by abundant and painful menstruations that can hinder the movement of the egg and its fertilization.

Other less common factors that can cause female infertility are:

  • Myomas: they are abnormal muscular tissue growths in the womb that can prevent a fertilized egg from implanting in the right place.
  • Weight problems: both obesity and an excessive loss of weight (such as anorexia) can alter sexual hormones, creating fertility problems.
  • Lifestyle: the consumption of toxic substances, such as alcohol or tobacco, as well as the presence of environmental contaminants, can reduce the woman's reproductive capacity.

Mixed fertility problems

They occur when both the man and the woman present one or more fertility problems mentioned above.

Unexplained fertility problems

These cases occur when there is no clear explanation for the couple's infertility. Sometimes this is associated with weight problems, excessive exercise, or environmental disorders but there's no direct association between fertility and these possible problems.

The fact the cause of sterility is not known (infertility of unknown origin) doesn't mean there is no cause. It simply means that current methods and the exams done to the couple cannot determine the reason why a pregnancy is not achieved.

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 Cristina Mestre Ferrer
Cristina Mestre Ferrer
B.Sc., M.Sc.
Bachelor's Degree in Biological Sciences, Genetics & Human Reproduction from the University of Valencia (UV). Master's Degree in Biotechnology of Human Assisted Reproduction from the UV and the Valencian Infertility Institute (IVI). Embryologist at IVI Barcelona. More information about Cristina Mestre Ferrer
Adapted into english by:
 Sandra Fernández
Sandra Fernández
B.A., M.A.
Fertility Counselor
Bachelor of Arts in Translation and Interpreting (English, Spanish, Catalan, German) from the University of Valencia (UV) and Heriot-Watt University, Riccarton Campus (Edinburgh, UK). Postgraduate Course in Legal Translation from the University of Valencia. Specialist in Medical Translation, with several years of experience in the field of Assisted Reproduction. More information about Sandra Fernández

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