refers to an inability to conceive after having regular unprotected
sex. Infertility can also refer to the biological inability of an
individual to contribute to conception, or to a female who cannot carry
a pregnancy to full term. In many countries infertility refers to a
couple that has failed to conceive after 12 months of regular sexual
intercourse without the use of contraception.Studies indicate that slightly over half of all cases of infertility
are a result of female conditions, while the rest are caused by either
sperm disorders or unidentified factors. According to The Mayo Clinic,
- About 20% of cases of infertility are due to a problem in the man.
- About 40% to 50% of cases of infertility are due to a problem in the woman.
- About 30% to 40% of cases of infertility are due to problems in both the man and the woman.
According to Medilexicon’s medical dictionary, infertility is “Diminished or absent ability to produce offspring; in either the male or the female, not as irreversible as sterility.”
According to the Department of Health and Human Services, USA,
approximately 10% to 15% of couples in the USA are infertile – meaning
they have not conceived after at least one year of regular, unprotected
Many cases of apparent infertility are treatable.
Infertility may have a single cause in one of the partners, or it could
be the result of a combination of factors.
Chances of conceiving within one year
In Europe, North America and much of the world approximately 85% of
couples will conceive within one year if they have regular unprotected
sex. Averages in the UK are as follows (National Health Service):
- 20% will conceive within one month
- 70% will conceive within six months
- 85% will conceive within 12 months
- 90% will conceive within 18 months
- 95% will conceive within 24 months
Therefore, doctors in the UK will not usually diagnose a couple as
infertile until 24 months have passed without conception and regular
unprotected sex. Most people will see their GP (general practitioner,
primary care physician) if there is no pregnancy within 12 months.
According to the National Health Service, UK, a couple that has been
trying to conceive for over three years has a maximum 25% chance of
conceiving over the subsequent 12 months if they continue trying. What
are the risk factors of infertility? In medicine, a risk factor is
something that raises the risk of developing a condition, disease or
symptom. For example, obese people are more likely to develop diabetes type 2 compared to people of normal weight; therefore, obesity is a risk factor for diabetes type 2.
– a woman’s fertility starts to drop after she is about 32 years old,
and continues doing so. A 50-year-old man is usually less fertile than a
man in his 20s (male fertility progressively drops after the age of
- Smoking – smoking
significantly increases the risk of infertility in both men and women.
Smoking may also undermine the effects of fertility treatment. Even
when a woman gets pregnant, if she smokes she has a greater risk of
- Alcohol consumption
– a woman’s pregnancy can be seriously affected by any amount of
alcohol consumption. Alcohol abuse may lower male fertility. Moderate
alcohol consumption has not been shown to lower fertility in most men,
but is thought to lower fertility in men who already have a low sperm
- Being obese or overweight
– in industrialized countries overweight/obesity and a sedentary
lifestyle are often found to be the principal causes of female
infertility. An overweight man has a higher risk of having abnormal
- Eating disorders – women who become seriously underweight as a result of an eating disorder may have fertility problems.
- Being vegan – if you are a strict vegan you must make sure your intake of iron, folic acid, zinc and vitamin B-12 are adequate, otherwise your fertility may become affected.
- Over-exercising – a woman who exercises for more than seven hours each week may have ovulation problems.
- Not exercising – leading a sedentary lifestyle is sometimes linked to lower fertility in both men and women.
- Sexually transmitted infections (STIs) – chlamydia
can damage the fallopian tubes, as well as making the man’s scrotum
become inflamed. Some other STIs may also cause infertility.
- Exposure to some chemicals – some pesticides, herbicides, metals (lead) and solvents have been linked to fertility problems in both men and women.
- Mental stress – studies indicate that female ovulation and sperm production may be affected by mental stress.
If at least one partner is stressed it is possible that the frequency
of sexual intercourse is less, resulting in a lower chance of
What are the causes of infertility? There
are many possible causes of infertility. Unfortunately, in about
one-third of cases no cause is ever identified.
Causes of infertility in women
- Ovulation disorders
– problems with ovulation are the most common cause of infertility in
women, experts say. Ovulation is the monthly release of an egg. In some
cases the woman never releases eggs, while in others the woman does
not release eggs during come cycles. Ovulation disorders can be due to:
- Premature ovarian failure – the woman’s ovaries stop working before she is 40.
(polycystic ovary syndrome) – the woman’s ovaries function abnormally.
She also has abnormally high levels of androgen. About 5% to 10% of
women of reproductive age are affected to some degree. Also called
- Hyperprolactinemia – if prolactin levels are high and the woman is not pregnant or breastfeeding, it may affect ovulation and fertility.
- Poor egg quality – eggs that are damaged or develop genetic abnormalities cannot sustain a pregnancy. The older a woman is the higher the risk.
- Overactive thyroid gland
- Underactive thyroid gland
- Some chronic conditions, such as AIDS or cancer.
- Scientists discover gene that explains infertility – scientists from the University of Edinburgh reported in the Journal of Cell Science that they identified a gene that controls a vital process in the formation of healthy fertile eggs.They say their breakthrough will help researchers better understand
how cells divide during reproduction, which in turn will help explain
low fertility and sterility.This gene allows chromosomes to
bunch up together. The authors believe that this huddling of
chromosomes secures the healthy development and subsequent
fertilization of an egg.They analyzed hundreds of infertile Drosophila oocytes (fruit flies) and found that without the gene SRPK, the chromosomes do not huddle together. This gene exists in human cells.
The researchers said that “the absence of SRPK ultimately leads to sterility and low fertility”.
- Problems in the uterus or fallopian tubesThe egg travels from the ovary to the uterus (womb) where the
fertilized egg grows. If there is something wrong in the uterus or the
fallopian tubes the woman may not be able to conceive naturally. This
may be due to:
– pelvic surgery can sometimes cause scarring or damage to the
fallopian tubes. Cervical surgery can sometimes cause scarring or
shortening of the cervix. The cervix is the neck of the uterus.
- Submucosal fibroids
– benign or non-cancerous tumors found in the muscular wall of the
uterus, occurring in 30% to 40% of women of childbearing age. They may
interfere with implantation. They can also block the fallopian tube,
preventing sperm from fertilizing the egg. Large submucosal uterine fibroids may make the uterus’ cavity bigger, increasing the distance the sperm has to travel.
- Endometriosis – cells that are normally found within the lining of the uterus start growing elsewhere in the body.
- Previous sterilization treatment
– if a woman chose to have her fallopian tubes blocked. It is possible
to reverse this process, but the chances of becoming fertile again are
not high. However,
an eight-year study showed tubal reversal surgery results in higher
pregnancy and live birth rates and is less costly than IVF.
- Medications – some drugs can affect the fertility of a woman. These include:
- Chemotherapy – some medications used in chemotherapy can result in ovarian failure. In some cases, this side effect of chemotherapy may be permanent.
- Radiotherapy – if radiation therapy was aimed near the womans reproductive organs there is a higher risk of fertility problems.
- Illegal drugs – some women who take marijuana or cocaine may have fertility problems.
Causes of infertility in men
Semen is the milky fluid that a man’s penis releases during orgasm.
Semen consists of fluid and sperm. The fluid comes from the prostate
gland, seminal vesicle and other sex glands. The sperm is produced in
the testicles. During orgasm a man ejaculates (releases semen through
the penis). The seminal fluid helps transport the sperm during
ejaculation. The seminal fluid has sugar in it – sugar is an energy
source for sperm.
Abnormal semen is responsible for about 75%
of all cases of male infertility. Unfortunately, in many cases doctors
never find out why. The following semen problems are possible:
- Low sperm count
(low concentration) – the man ejaculates a lower number of sperm,
compared to other men. Sperm concentration should be 20 million sperm
per milliliter of semen. If the count is under 10 million there is a
low sperm concentration (subfertility).
- No sperm – when the man ejaculates there is no sperm in the semen.
- Low sperm mobility (motility) – the sperm cannot “swim” as well as it should.
- Abnormal sperm – perhaps the sperm has an unusual shape, making it more difficult to move and fertilize an egg.
Sperm must be the right shape and able to travel rapidly and
accurately towards the egg. If the sperm’s morphology (structure) and
motility (movement) are wrong it is less likely to be able to reach the
egg and fertilize it.
The following may cause semen to be abnormal:
- Testicular infection
- Testicular cancer
- Testicular surgery
- Overheating the testicles
– frequent saunas, hot tubs, very hot baths, or working in extremely
hot environments can raise the temperature of the testicles. Tight
clothing may have the same effect on some people.
- Ejaculation disorders
– for some men it may be difficult to ejaculate properly. Men with
retrograde ejaculation ejaculate semen into the bladder. If the
ejaculatory ducts are blocked or obstructed the man may have a problem
- Varicocele – this is a varicose vein in the scrotum that may cause the sperm to overheat.
- Undescended testicle
– one (or both) testicle fails to descend from the abdomen into the
scrotum during fetal development. Sperm production is affected because
the testicle is not in the scrotum and is at a higher temperature.
Healthy sperm need to exist in a slightly lower-than-body temperature.
That is why they are in the scrotum, and not inside the body.
- Hypogonadism – testosterone deficiency can result in a disorder of the testicles.
- Genetic abnormality
– a man should have an X and Y chromosome. If he has two X chromosomes
and one Y chromosome (Klinefelter’s syndrome) there will be an
abnormal development of the testicles, low testosterone, and a low
sperm count (sometimes no sperm at all).
- Mumps – this viral infection usually affects young children. However, if it occurs after puberty inflammation of the testicles may affect sperm production.
– the urethral opening is at the underside of the penis, instead of
its tip. This abnormality is usually surgically corrected when the male
is a baby. If it is not the sperm may find it harder to get to the
female’s cervix. Hypospadias occur in about 1 in every 500 newborn
- Cystic fibrosis –
Cystic fibrosis is a chronic disease that affects organs such as the
liver, lungs, pancreas, and intestines. It disrupts the body’s salt
balance, leaving too little salt and water on the outside of cells and
causing the thin layer of mucus that usually keeps the lungs free of
germs to become thick and sticky. This mucus is difficult to cough out,
and it clogs the lungs and airways, leading to infections and damaged
lungs. Males with cystic fibrosis
commonly have a missing or obstructed vas deferens (tube connecting
the testes to the urethra; it carries sperm from the epididymis to the
ejaculatory duct and the urethra).
– radiation therapy can impair sperm production. The severity usually
depends on how near to the testicles the radiation was aimed.
- Some diseases – the following diseases and conditions are sometimes linked to lower fertility in males:Anemia
- Cushing’s syndrome
- Thyroid disease
- - this anti-inflammatory drug can significantly lower a man’s sperm count. The drug is often prescribed for patients with
- . Usually this side effect goes away after the patient stops taking the medication.
- - often taken by bodybuilders and athletes; anabolic steroids,
- especially after long term use can seriously reduce sperm count and
- - some medicines may significantly reduce sperm count.
- Illegal drugs – consumption of marijuana and cocaine can lower a man’s sperm count.
Diagnosing infertility Most people will visit their GP (general
practitioner, primary care physician) if there is no pregnancy after 12
months of trying. For anybody who is concerned about fertility,
especially if they are older (women over 35), it might be a good idea
to see a doctor earlier. As fertility testing can sometimes take a long
time, and female fertility starts to drop when a woman is in her
thirties, seeing the doctor earlier on if you are over 35 makes sense.
A GP can give the patient advice and carry out some preliminary
assessments. As it takes two to make a baby it is better for both the
male and female to see the doctor together.
testing for fertility it is important that the couple be committed. The
doctor will need to know what the patients’ sexual habits are, and may
make recommendations regarding them. Tests and trials might extend
over a long period. Even after thorough testing, no specific cause is
ever found for 30% of infertility cases.
In some countries where universal healthcare cover does not exist, evaluation and eventual treatment may be expensive.
Tests for males
- General physical exam
– the doctor will ask the man about his medical history, medications,
and sexual habits. The physician will also carry out an examination of
his genitals. The testicles will be checked for lumps or deformities,
while the shape and structure of the penis will be examined for any
- Semen analysis
– the doctor may ask for some specimens of semen. They will be
analyzed in a laboratory for sperm concentration, motility, color,
quality, infections and whether any blood is present. As sperm counts
can fluctuate, the man may have to produce more samples.
- Blood test – the lab will test for several things, including the man’s level of testosterone and other male hormones.
- Ultrasound test – the doctor will determine whether there is any ejaculatory duct obstruction, retrograde ejaculation, or other abnormality.
- Chlamydia test – if the man is found to have Chlamydia, which can affect fertility, he will be prescribed antibiotics to treat it.
Tests for females
- General physical exam
– the doctor will ask the woman about her medical history,
medications, menstruation cycle, and sexual habits. She will also
undergo a gynecological examination.
- Blood test
– several things will be checked, for example, whether hormone levels
are correct and whether the woman is ovulating (progesterone test).
– fluid is injected into the woman’s uterus which shows up in X-ray
pictures. X-rays are taken to determine whether the fluid travels
properly out of the uterus and into the fallopian tubes. If the doctor
identifies any problems, such as a blockage, surgery may need to be
– a thin, flexible tube with a camera at the end (laparoscope) is
inserted into the abdomen and pelvis to look at the fallopian tubes,
uterus and ovaries. A small incision is made below the belly button and
a needle is inserted into the abdominal cavity; carbon dioxide is
injected to create a space for the laparoscope. The doctor will be able
to detect endometriosis, scarring, blockages, and some irregularities of the uterus and fallopian tubes.
- Ovarian reserve testing – this is done to find out how effective the eggs are after ovulation.
- Genetic testing – this is to find out whether a genetic abnormality is interfering with the woman’s fertility.
- Pelvic ultrasound
– high frequency sound waves create an image of an organ in the body,
which in this case is the woman’s uterus, fallopian tubes, and ovaries.
- Chlamydia test – if the woman is found to have Chlamydia, which can affect fertility, she will be prescribed antibiotics to treat it.
- Thyroid function test – according to the National Health Service (UK) between 1.3% and 5.1% of infertile women have an abnormal thyroid.
What are the treatment options for infertility? This will depend on
many factors, including the age of the patient(s), how long they have
been infertile, personal preferences, and their general state of
health. Even if the woman has causes that cannot be corrected, she may
still become pregnant.
Frequency of intercourse
The couple may be advised to have sexual intercourse more often. Sex
two to three times per week may improve fertility if the frequency was
less than this. Some fertility experts warn that too-frequent sex can
lower the quality and concentration of sperm. Male sperm can survive
inside the female for up to 72 hours, while an egg can be fertilized
for up to 24 hours after ovulation.
Fertility treatment for men
- Erectile dysfunction or premature ejaculation – medication and/or behavioral approaches can help men with general sexual problems, resulting in possibly improved fertility.
- Varicocele – if there is a varicose vein in the scrotum, it can be surgically removed.
- Blockage of the ejaculatory duct – sperm can be extracted directly from the testicles and injected into an egg in the laboratory.
- Retrograde ejaculation – sperm can be taken directly from the bladder and injected into an egg in the laboratory.
- Surgery for epididymal blockage
– if the epididymis is blocked it can be surgically repaired. The
epididymis is a coil-like structure in the testicles which helps store
and transport sperm. If the epididymis is blocked sperm may not be
Fertility treatment for women
- Ovulation disorders
– if the woman has an ovulation disorder she will probably be
prescribed fertility drugs which regulate or induce ovulation. These
(Clomid, Serophene) – this medication helps encourage ovulation in
females who do not ovulate regularly, or who do not ovulate at all,
because of polycystic ovary syndrome (PCOS) or some other disorder. It
makes the pituitary gland release more FSH (follicle-stimulating
hormone) and LH (luteinizing hormone).
(Glucophage) – women who have not responded to Clomifene may have to
take this medication. It is especially effective for women with PCOS,
especially when linked to insulin resistance.
- Human menopausal gonadotropin, or hMG, (Repronex)
– this medication contains both FSH and LH. It is an injection and is
used for patients who don’t ovulate on their own because of a fault in
their pituitary gland.
- Follicle-stimulating hormone (Gonal-F, Bravelle)
– this is a hormone produced by the pituitary gland that controls
estrogen production by the ovaries. It stimulates the ovaries to mature
- Human chorionic gonadotropin (Ovidrel, Pregnyl) – this medication is used together with clomiphene, hMG and FSH. It stimulates the follicle to ovulate.
- Gn-RH (gonadotropin-releasing hormone) analogs
– for women who ovulate prematurely, before the lead follicle is
mature enough during hmG treatment. This medication delivers a constant
supply of Gn-RH to the pituitary gland, which alters the production of
hormone, allowing the doctor to induce follicle growth with FSH.
(Parlodel) – this drug inhibits prolactin production. Prolactin
stimulates milk production in breast feeding mothers. If non-pregnant,
non-breast feeding women have high levels of prolactin they may have
irregular ovulation cycles and have fertility problems.
Risk of multiple pregnancies
Injectable fertility drugs can sometimes be the victims of their own
success and cause multiple births – when the woman gets pregnant she has
twins, triplets, or perhaps more babies in one go. Oral fertility
drugs also raise the risk of multiple pregnancies, but much less so
than injectable ones. It is important to monitor the patient carefully
during treatment and pregnancy. The more babies the mother carries
inside her the higher is her risk of premature labor.
If a woman needs an HCG injection to activate ovulation and ultrasound
scans show that too many follicles have developed, it is possible to
withhold the HCG injection. Couples may decide to go ahead regardless if
the desire to become pregnant is very strong.
pregnancy reduction is possible if too many babies are conceived – one
or more of the fetuses is removed. Couples will have to consider the
ethical and emotional aspects of this procedure.
- Surgical procedures for women
- Fallopian tube surgery – if the fallopian tubes are blocked or scarred surgery may repair them, making it easier for eggs to pass through them.
- Laparoscopic surgery
– a small incision is made in the woman’s abdomen. A thin, flexible
microscope with a light at the end (laparoscope) is inserted through
the incision. The doctor can then look at internal organs, take samples
and perform small operations. For women with endometriosis,
laparoscopy removes implants and scar tissue, reducing pain and often
- IUI (intrauterine insemination)
– a fine catheter is inserted through the cervix into the uterus to
place a sperm sample directly into the uterus. The sperm is washed in a
fluid and the best specimens are selected. This procedure must be done
when ovulation occurs. The woman may be given a low dose of ovary
stimulating hormones.IUI is more commonly done when the man
has a low sperm count, decreased sperm motility, or when infertility
does not have an identifiable cause. The procedure is also helpful for
males suffering from severe erectile dysfunction.
- IVF (in vitro fertilization)
– sperm are placed with unfertilized eggs in a Petri dish; the aim is
fertilization of the eggs. The embryo is then placed in the uterus to
begin a pregnancy. Someitmes the embryo is frozen for future use
(cryopreserved). Louise Joy Brown, born in England in 1978, was the
world’s first IVF baby. Before IVF is done the female takes fertility
drugs to encourage the ovaries to produce more eggs than normal.Time-lapse imaging triples the chances of having a baby for couples undergoing IVF treatment, researchers reported in Reproductive BioMedicine Online
(May 2013 issue). Described as a “major breakthrough”, time-lapse
imaging became available in 2013 in the UK for monitoring the
development of IVF embryos before they are implanted in the womb.In an Abstract in the journal, the authors wrote “Time-lapse imaging
of human preimplantation IVF embryos has enabled objective algorithms
based on novel observations of development (morphokinetics) to be used
for clinical selection of embryos.”With this new technique,
the scientists could develop a way of accurately identifying which
embryos are more likely to have aneuploidy (abnormal chromosomes).
Embryos with aneuploidy are much less likely to be successfully
The researchers, from CARE Fertility, said further large-scale studies are needed to confirm their findings.
Researchers from Mount Sinai Hospital in Toronto, Canada, reported in CMAJ that IVF is more successful if the woman has sufficient levels of vitamin D.
- ICSI (Intracytoplasmic sperm injection)
– a single sperm is injected into an egg to achieve fertilization
during an IVF procedure. The likelihood of fertilization improves
significantly for men with low sperm concentrations.
- Donation of sperm or egg
– if there is either no sperm or egg in one of the partners it is
possible to receive sperm or eggs from a donor. Fertility treatment
with donor eggs is usually done using IVF. In the UK and a growing
number of countries the egg donor can no longer remain anonymous – the
offspring can legally trace his/her biological parent when reaching the
age of 18.
- Assisted hatching
– this improves the chances of the embryo’s implantation; attaching to
the wall of the uterus. The embryologist opens a small hole in the
outer membrane of the embryo, known as the zona pellucid.
The opening improves the ability of the embryo to leave its shell and
implant into the uterine lining. Patients who benefit from assistant
hatching include women with previous IVF failure, poor embryo growth
rate, and older women. In some women, particularly older women, the
membrane is hardened, making it difficult for the embryo to hatch and
- Electric or vibratory stimulation to achieve ejaculation
– ejaculation is acheived with electric or vibratory stimulation. This
procedure is useful for men who cannot ejaculate normally, such as
those with a spinal cord injury.
- Surgical sperm aspiration – the sperm is removed from part of the male reproductive tract, such as the vas deference, testicle or epididymis.
What are the complications of infertility treatment?
- Ovarian hyperstimulation syndrome (OHSS)The ovaries become very swollen, leaking excess fluid into the body.
The ovaries produce too many follicles (small fluid sacs in which an
egg develops). OHSS usually occurs as a result of taking medications to
stimulate the ovaries, such as clomifene and gonadtrophins, and can
also develop after IVF. Symptoms can include:
In most cases symptoms are mild and easy to treat. On very rare
occasions the patient may develop a blood clot (thrombosis) in an artery
or vein, liver or kidney problems, and respiratory distress. In very
severe cases OHSS can be potentially fatal.
- Ectopic pregnancyThis is a pregnancy when the fertilized egg does not implant in the
womb – in most cases the fertilized egg grows in the fallopian tube. If
it stays in the fallopian tube the mother will usually miscarry before
complications develop, such as the rupture of the fallopian tube.
Women receiving fertility treatment have a slightly higher risk of
having an ectopic pregnancy. An ultrasound scan can detect an ectopic
- Coping mentallyAs it is impossible to know how long treatment will go on for and how
successful it will be, coping and persevering can be stressful. The
emotional toll on both partners might be considerable and can have an
impact on their relationship. Some people find that joining a support
group helps – being able to talk to others who share similar problems,
aspirations and anxieties
can be uplifting. It is important to tell your doctor if you are
suffering mentally and/or emotionally. Most fertility doctors have
access to counselors, as well as other people and professionals who can
offer helpful support.