Infertility: Causes of fertility problems

Partners often see a pregnancy as the culmination of a relationship. When infertility occurs, a couple is unable to get pregnant after twelve months of regular intercourse without contraception. The problem lies with the man and/or woman. Many conditions as well as environmental factors contribute to infertility. Other symptoms may or may not be present. Safe and effective treatment is often available, allowing a woman to become pregnant. These treatments sometimes involve complications.

  • Epidemiology
  • Types of infertility
  • Female infertility
  • Causes
  • Risk factors
  • Diagnosis and examinations
  • Therapy
  • Male infertility
  • Causes
  • Risk factors
  • Diagnosis and examinations
  • Therapy
  • Assisted fertilization
  • Surgical sperm aspiration
  • Electrical or vibrating stimulation
  • Assisted reproduction
  • Intracytoplasmic sperm injection (ICSI)
  • Intrauterine insemination (IUI)
  • In vitro fertilization (IVF)
  • Sperm or egg donation
  • Prognosis
  • Complications of fertility treatment



About ten percent of women aged 15 to 44 have difficulty becoming pregnant. Worldwide, 8 to 12 percent of couples experience fertility problems. In about a third of cases, the problem of infertility lies with the man. In another third of cases, there is a problem with the woman. In the remaining cases, there are problems with both the man and the woman, or a clear cause is absent.

Types of infertility

There are two types of infertility. In primary infertility, a couple is unable to get pregnant after at least one year of sexual intercourse without using contraceptive methods. Secondary infertility refers to a couple who has gotten pregnant at least once but is now unable to get pregnant.

Female infertility


Female infertility occurs in the following conditions

  • the fertilized egg does not attach to the inside of the uterus
  • the eggs cannot move from the ovaries to the uterus
  • the ovaries have problems producing eggs
  • a fertilized egg or embryo does not survive if it attaches to the wall of the uterus (uterus)


Risk factors

Conditions and medical treatments Conditions and medical treatments that lead to female infertility include:

  • congenital defects that affect the reproductive system
  • autoimmune diseases, such as antiphospholipid syndrome
  • surgery to prevent pregnancy (tubal ligation) or failure of tubal ligation reversal (reanastomosis)
  • diabetes mellitus
  • a pelvic infection resulting in scarring or swelling of the fallopian tubes (hydrosalpinx: blocked fallopian tubes due to fluid retention) or a pelvic inflammatory disease
  • a growth (such as fibroids or polyps) in the uterus and cervix
  • a high cholesterol level in the blood
  • a thyroid condition
  • eating disorders or poor nutrition with severe weight loss
  • ovarian cysts and polycystic ovarian syndrome
  • hormonal changes
  • cancer or a tumor
  • scars due to a sexually transmitted disease, surgery to the abdominal area or endometriosis (pain around the menstrual period in a woman)
  • mental stress
  • ovulation problems (problems with monthly ovulation)
  • radiotherapy
  • sexually transmitted diseases such as chlamydia
  • clotting disorders
  • vitamin deficiencies: a lack of folic acid, an iron deficiency, zinc deficiency and a vitamin B12 deficiency

 Smoking increases the risk of infertility / Source: Geralt, PixabayEnvironmental factors Environmental factors also increase the risk of female infertility :

  • exposure to certain chemicals such as pesticides, solvents, herbicides
  • exposure to certain metals, such as lead
  • drug abuse (marijuana, cocaine)
  • the use of drugs such as chemotherapy, NSAIDs
  • Age: Healthy couples under the age of thirty who regularly practice sexual intercourse have a 25% to 30% chance of becoming pregnant each month. A woman is most fertile in the first half of the second decade (20-25 years). The chance that a woman will become pregnant decreases sharply after the age of 35 (and especially after the age of 40). The age at which fertility begins to decline varies from woman to woman. Fertility problems and miscarriage rates increase significantly after the age of 35.
  • excessive use of alcohol
  • smoking
  • too much or too little exercise
  • obesity


Diagnosis and examinations

A woman undergoes a general physical examination after the doctor asks the woman about her medical history, medication use, menstrual cycle and sexual habits. A gynecological examination is necessary. A number of studies are also useful:

  • a blood test: determines hormone levels and whether a woman is ovulating.
  • an ultrasound scan of the pelvic area
  • a genetic study
  • a hysterosalpingography: After an injection of fluid into the uterus, x-rays are taken to determine whether the fluid comes out of the uterus and the fallopian tubes properly. If a blockage occurs, surgery is necessary.
  • a laparoscopy: insertion of a thin tube with a camera to examine and possibly remove suspicious tissue. This examination reveals signs of endometriosis, scarring, blockages and some irregularities of the uterus and fallopian tubes.
  • a thyroid function test (thyroid problems may affect the hormonal balance)
  • a test for detecting chlamydia



Medication The doctor prescribes fertility drugs to regulate or induce ovulation.

  • Clomiphene (Clomid, Serophene): This medication stimulates ovulation in women who ovulate irregularly or not at all due to polycystic ovary syndrome or another condition. This causes the pituitary gland to release more follicle-stimulating hormone (FSH) and luteinizing hormone (LH).
  • Metformin (Glucophage): If Clomiphene is not effective, the doctor prescribes metformin for women with PCOS, especially if they are linked to insulin resistance (cells are insensitive to insulin).
  • Human menopausal gonadotropin or hMG (Repronex): This drug is given to a woman who is not ovulating due to a defect in the pituitary gland. The drug given by injection contains both FSH and LH.
  • Follicle-stimulating hormone (Gonal-F, Bravelle): The pituitary gland produces this hormone, which is necessary for the regulation of estrogen production by the ovaries. The hormone stimulates the ovaries to mature the egg follicles.
  • Human chorionic gonadotropin (Ovidrel, Pregnyl): The doctor prescribes this medication in combination with clomiphene, hMG and FSH. This drug stimulates the follicle to ovulate.
  • Gonadotropin-releasing hormone (Gn-RH) analogues: These medications help women who ovulate too early. The drug provides a constant supply of Gn-RH to the pituitary gland, which alters the production of hormones, allowing the doctor to induce follicle growth with FSH.
  • Bromocriptine (Parlodel): This drug inhibits prolactin production. Prolactin stimulates milk production during breastfeeding. Outside of pregnancy and breastfeeding, women with high prolactin levels have irregular ovulation cycles and fertility problems.

Surgery If the fallopian tubes are blocked or scarred, surgical repair is necessary. The doctor treats endometriosis by laparoscopic surgery. He makes a small incision (surgical incision) in the abdomen and then places a thin , flexible microscope with a light at the end in the abdomen. The surgeon removes scar tissue, which reduces pain and promotes fertility.Storing eggs Women can have eggs removed and stored at the beginning of their second decade, allowing them to have a successful pregnancy after the age of 35. This is an expensive option, but it may be useful for women who know they will have to delay fertility.

Male infertility


Male infertility is due to

  • defects in the sperm, for example an abnormal shape
  • abnormal sperm production
  • a blockage that prevents the sperm from being released
  • a low sperm count
  • low sperm motility


Risk factors

Conditions and medical treatments Male infertility may result from the following conditions and:

  • congenital abnormalities
  • anemia
  • Mumps: If this occurs after puberty, it may cause inflammation of the testicles, affecting sperm production.
  • diabetes mellitus
  • a hereditary condition: Kallmann syndrome, Kartagener syndrome
  • an infection
  • a varicose vein in the scrotum (varicocele)
  • a vasectomy (male sterilization) or failure to reverse a vasectomy
  • Klinefelter syndrome
  • Cushing’s syndrome (too much cortisol in the body)
  • hormonal imbalances
  • hypospadias (opening of the urethra at the base of the penis)
  • impotence
  • cancer treatments, including chemotherapy and radiotherapy
  • scars due to sexually transmitted infections (STDs such as chlamydia), an injury or surgery
  • mental stress
  • cystic fibrosis (cystic fibrosis with blockage of organs)
  • undescended testicles
  • retrograde ejaculation
  • thyroid disorders

 Obese men are more likely to suffer from fertility problems / Source: Tobyotter, Flickr (CC BY-2.0)Environmental factors Some environmental factors lead more quickly to men being infertile:

  • alcohol abuse
  • the exposure to high heat for long periods (for example, spending long periods of time in hot tubs)
  • exposure to toxins in the environment such as pesticides
  • drug abuse (marijuana or cocaine)
  • the use of drugs such as sulfasalazine, anabolic steroids, chemotherapy; Long-term use of paracetamol during pregnancy may also affect fertility in men by reducing testosterone production. Women are therefore advised not to use the drug for more than one day.
  • Age: After the age of 40, fertility declines in men
  • smoking
  • obesity


Diagnosis and examinations

The doctor questions the man about his medical history, medication use and sexual habits and performs a physical examination. The doctor examines the testicles for the presence of lumps or deformities and also checks for any abnormalities in the shape and structure of the penis. The following studies are still useful:

  • a blood test: measuring testosterone levels and amounts of other hormones
  • an ultrasound: an ultrasound reveals problems such as ejaculatory duct obstruction or a retrograde ejaculation.
  • a semen analysis: an examination of the sperm concentration, motility, color, quality, possible infections and whether blood is present
  • a test to detect chlamydia (if present, antibiotic treatment is required)
  • a testicular biopsy



Treatment in men depends on the underlying cause of the infertility.

  • Surgery for epididymal blockage: Surgical repair is necessary for a blocked epididymis. The epididymis is a spindle-like structure in the testicles that stores and transports sperm. If the epididymis is blocked, sperm cannot be ejaculated properly.
  • Erectile dysfunction or premature ejaculation: Medication and/or a behavioral approach improve fertility
  • Retrograde ejaculation: The doctor takes sperm directly from the bladder and injects it into an egg in a laboratory.
  • Varicocele: Surgical removal of a varicose vein in the scrotum improves fertility
  • Blockage of the ejaculatory duct: The doctor takes sperm directly from the testicles and injects it into an egg in a laboratory.


Assisted fertilization

Surgical sperm aspiration

Surgically obtained semen comes from a part of the male reproductive tract, such as the vas deferens, testicle, or epididymis.

Electrical or vibrating stimulation

Using this method, the man achieves ejaculation with electrical or vibrating stimulation. This is useful for a man who cannot ejaculate normally, for example due to a spinal cord injury.

Assisted reproduction

The embryologist opens a small hole in the outer membrane of the embryo (zona pellucida). This allows the embryo to implant better in the uterine lining. This improves the chance that the embryo will implant or attach to the uterine wall. Especially in older women, the membrane becomes harder, making it more difficult for the embryo to implant. This method is useful if IVF has not been effective, if the embryonic growth rate is low and if the woman is older.

Intracytoplasmic sperm injection (ICSI)

The doctor injects a single sperm into an egg to achieve fertilization during an IVF procedure. The chance of conception improves significantly for men with low sperm concentrations.

Intrauterine insemination (IUI)

At the time of ovulation, the doctor places a fine catheter through the cervix into the uterus to introduce a sperm sample directly into the uterus. Only the best specimens end up in the womb. The woman receives a low dose of ovary-stimulating hormones. IUI is more likely to occur if the man has a low sperm count, reduced sperm motility, or if infertility has no identifiable cause. It also helps a man who suffers from severe erectile dysfunction.

In vitro fertilization (IVF)

With IVF, the doctor places sperm with unfertilized eggs in a petri dish, where fertilization then takes place. The doctor then places the embryo in the uterus to initiate a pregnancy. Sometimes the embryo is frozen for future use.

Sperm or egg donation

If necessary, sperm or eggs from a donor are available. Fertility treatment with donor eggs is usually done using IVF.


It is impossible to know the duration of treatment or whether it will be successful. This is sometimes mentally stressful and exhausting and may take an emotional toll on both partners. Joining a support group can help.

Complications of fertility treatment

Infertility treatments may be associated with the following complications

  • bleeding or infection
  • a multiple pregnancy
  • Ovarian hyperstimulation syndrome: Fertility medications used to induce ovulation cause swollen and painful ovaries. Common symptoms of this include mild abdominal pain, bloating and nausea that lasts for about one week, or longer if a woman is pregnant. Rarely, a more severe form of the condition causes rapid weight gain and shortness of breath that requires emergency treatment.


read more

  • Testicle biopsy: Removal of a piece of tissue from the testicle
  • Klinefelter syndrome: Small testicles and infertility
  • Prolactinoma: Benign pituitary tumor with infertility
  • Female infertility (female infertility)
  • Male infertility (male infertility)