For most couples, the decision to start a family is both emotive and exciting. But there can also be an element of trepidation as most people understand that this decision will, more than likely, change their lives forever. Most couples will have little or no understanding of the process of conception and growth of their baby within the womb. Quite rightly, this is a "natural" process, with the most important factor being the birth of a healthy and happy baby.

Although this does happen for the majority of couples, there is a sizable minority where things don't quite work as naturally as they should. The reasons for having difficulty conceiving are numerous and complex and are discussed in some depth in the following few pages. If you are such a couple (or individual), then this guide to assisted conception (also commonly known as infertility) is for you.

In the world of reproductive medicine, there are numerous terms that are used which mean very specific things. It is therefore important to understand some of the basic terms that you will hear.

• Infertility: this is when an otherwise healthy couple cannot conceive (fall pregnant) despite taking the usual steps such as having regular sexual intercourse without the use of any contraception. This happens in the minority of apparently "infertile" couples.
• Subfertility: this is when there is some difficulty falling pregnant but it is possible, perhaps with some medical assistance. It may take subfertile couples longer than average to conceive. Couples are also subfertile if they do conceive but keep having miscarriages. The majority of couples who are treated in infertility clinics are subfertile rather than infertile.
• Primary Infertility: this is where a couple have never managed to conceive.
• Secondary Infertility: this is where a couple are presently having difficult conceiving but where they have previously managed to conceive and either gone on to deliver a normal baby, a stillbirth or have suffered recurrent miscarriages.

Typical Symptoms

How Long Does It Normally Take to get Pregnant?

Falling pregnant can take a long time. But as a starting point, couples may wish to consult a doctor after approximately one year of trying without contraception. This is certainly true for women aged 35 years or above as these women may take longer to conceive. It is thought that around 1 in 7 couples have some difficulty with conception. However, generally, the average time taken for couples to fall pregnant can be viewed like this;- 20% of couples will conceive within 1 month;

 

- 40% of couples will conceive within 3 months; - 70% of couples will conceive within 6 months; - 85% of couples will conceive within 1 year; - 95% of couples will conceive within 2 years.

There are many factors that can change the time taken for conception to occur. The most important include;

• Maternal Age: normally, most women reach their peak fertility in their mid twenties. After they reach 30 years of age, fertility levels start to decline until women reach 35 years of age. Thereafter, fertility levels decline much more steeply and after reaching 40 years of age, this rate of decline is steeper still. Therefore, as a general rule, the older a women is after age 35, the longer she will take to fall pregnant.
• Disturbances of the Menstrual Cycle (causing Irregular Periods): the more irregular your periods are, the more difficulty you will have in accurately determining the date of ovulation. Ovulation is when an ovary sheds a mature egg, ready to be fertilized. This is therefore the most fertile time in a woman's menstrual cycle.
• The Time Already Taken in Trying to Conceive: as is shown above with average couples falling pregnant after different times, if you have not fallen pregnant within one year, there may potentially be a problem. However, this is not always the case as even after one year, many couples will naturally fall pregnant in their second year of trying. It may be prudent to discuss the situation with your doctor after the first year so that problems can be identified earlier.
• Frequency of Sexual Intercourse: the more frequent a couple has sex, the more likely they are to conceive. This is especially true for sex around the time of ovulation. Couples may try many methods to identify as precisely as possible the exact date of ovulation to maximise their chances of conception. Some of these factors are outlined in the following pages. However, although this is important, it is also vital that couples remain intimate and loving, thus reducing stress and tension in their relationship which can itself be a contributory factor in infertility.
• The Type of Contraception Previously Used: if you have used a barrier method of contraception such as sheaths (male or female condoms), caps or diaphragms, then your ability to conceive quickly should not be altered as you should be able to conceive immediately on stopping these methods. However, the situation with many hormonal methods is more uncertain in that a women may not be able to conceive for some weeks or months after stopping such contraception. Examples of hormonal methods include; the combined oral contraceptive pill (COC), progesterone only pill (POP), combined patch, depo injections, implants and intra-uterine devices. In theory, a women may conceive within just a few days after stopping any of these hormonal methods, but in practice, ovulation may be delayed, thus delaying conception.
• Other Medical Conditions: almost any chronic condition which is not treated adequately can lead to difficulty with conception. Examples include heart disease and diabetes.

In order to avoid getting disheartened by your failure to conceive, it is vital to understand the above points and recognise the appropriate timescales involved in falling pregnant. It is equally vital to have some knowledge about the normal menstrual cycle. For further information, please read the page entitled, "Understanding the Normal Menstrual Cycle".

What is Fertilisation?

For conception to occur it requires a male and female gamete. The male gamete is the sperm and the female gamete is the egg (also called an ovum or oocyte). Eggs are released from the ovary by a process known as ovulation. When a male and female gamete come together and fuse, a zygote is formed. In other words, when a single sperm burrows into an egg, the two fuse together in a process called fertilisation, thus forming a fertilised egg (a zygote). Fertilisation generally occurs in a fallopian tube.

What is Implantation?

After fertilisation, the zygote travels down into the uterus (womb) which at this stage will be receptive to this fertilised egg. In this state the fertilised egg attaches itself to the womb lining called the endometrium. The process of attachment is called implantation. It then grows to form an embryo which may then develop into a foetus.

When a zygote undergoes cell division it is called an embryo. An embryo aged 5 to 6 days is called a blastocyst. When an embryo reaches 8 weeks old it is then called a foetus. The age of the foetus is known as its gestational age and is usually expressed in weeks.

It is only after implantation has occurred that a woman is pregnant. For a pregnancy to take place, many different things must be in place. For example, the environment for an egg and sperm to meet must be right. Therefore, the timing of sexual intercourse is important and the structure of the fallopian tubes and uterus must be normal. The hormonal balance of the body must also be conducive to falling pregnant.

Understanding The Menstrual Cycle

To understand more about the causes of infertility it is important to have some knowledge of the normal menstrual cycle. The most important part of this cycle as far as pregnancies are concerned is ovulation.

Understanding Ovulation

Understanding the process of ovulation can greatly speed up the process of falling pregnant. Girls are born with a large number of eggs in each ovary. Girls have to wait until puberty before ovulation begins. Ovulation occurs when a mature egg is released by an ovary. This occurs approximately once a month for the average woman. Girls will start menstruating during the process of puberty and the date of first menses (a period bleed) is called menarche.

The average woman has a menstrual cycle between 21 and 35 days long. Day 1 of the cycle is defined as the first day of a proper period bleed. The last day is defined as the day before the next period bleed. Although ovulation may occur at any time in the menstrual cycle, there are general rules to determine more accurately when ovulation may take place. Ovulation is thought to occur most often approximately 14 days before the end of a menstrual cycle. At ovulation a woman is at her most fertile. Peak fertility is therefore thought to be approximately 2 days either side of ovulation. Therefore, for a woman with a 23 day cycle, peak fertility would occur during Days 7 to 11. For a woman with a 28 day cycle, peak fertility would occur during Days 12 to 16. For a woman with a 35 day cycle, peak fertility would occur on days 19 to 23.

From the above, it follows that in those women with irregular cycles, the date of ovulation (and therefore peak fertility) cannot be predicted using the time of the cycle alone. Other methods are required to assist in predicting ovulation. These include;

Measurement of Basal Body Temperature (BBT): your body has the ability to maintain a fairly constant temperature. However, progesterone is released by the ovary during ovulation. This causes a very slightly elevation in BBT by up to 0.5 degrees Celsius. This method is not particularly reliable as this increase is not only small, but also occurs 1-2 days after ovulation. Thus, ovulation may already have occurred before you recognise the temperature elevation. For this reason, it is important to chart your daily temperatures throughout the cycle to see if there are any patterns in your temperature fluctuations which may indicate when ovulation is about to occur.

Examination of Cervical Mucous: this is a more reliable method of predicting ovulation. The function of mucous produced by the cervix varies during the different stages of the menstrual cycle. The mucous forms a barrier at the entrance of the womb throughout the cycle before and after ovulation to block sperm from entering the womb when there is no chance of pregnancy. But as ovulation approaches, the cervix produces more mucous until at the time of ovulation itself, the mucous becomes stretchy and clear. At this time, the mucous, rather than blocking sperm, actually protects the sperm and aids the sperm to pass through the cervix and onto the egg in the hope that fertilisation may take place.

In an average 28 day cycle, the vaginal and mucous changes may appear as follows;

- Day 1-5: menstruation - blood. - Day 6-9: there is minimal mucous production and the vagina is dry. - Day 10-12: sticky and thick mucous can be seen. This eventually becomes thinner and more white. - Day 13-15: as ovulation occurs, the mucous becomes thinner still, clearer, stretchy and slippery. - Day 16-21: the mucous reverts back to being sticky and thick. - Day 22-28: the vagina becomes drier with little or no mucous.

Assessing the Position of the Cervix: assessing your cervical position also helps to predict the date of ovulation. This is done by inserting 2 fingers into your vagina and feeling for the location, consistency and wetness of the cervix which is located at the top end of the vagina. Normally, the cervix feels hard and dry. But during ovulation, the position of the cervix changes - it becomes higher. It also becomes softer and wetter to feel.

Ovulation Predictor Kits (OPKs): in some countries, OPKs can be bought from pharmacies and are particularly useful for women with irregular menstrual cycles. These kits work by detecting luteinising hormone in urine. This hormone is released by the pituitary gland and increases 12-36 hours before ovulation. The kits detect this surge and ovulation is them assumed to be imminent. However, conditions such as Polycystic Ovaries can make these tests unreliable.

What is a Menstrual Cycle?

On average, most women have a regular 28 day cycle. But many women have cycles that are a few days shorter or a few days longer than this. Cycles which last from 21 days to 35 days are deemed to be normal. Even amongst an individual woman, cycle lengths can vary from month to month. A variation of a few days is normal. However, the greater the variation each month, the more difficult it is to predict ovulation (as discussed above).

A normal 28 day cycle looks as follows;

- Days 1-5: Menstrual period or bleed. - Days 6-14: The bleeding subsides as menses ends. At this point, the lining of the uterus called the endometrium is thin. As the days progress, the endometrium thickens in preparation for possible implantation of a fertilised egg. - Days 15-28: The endometrium continues to thicken and prepare for a possible pregnancy. However, if fertilisation has not occurred, the endometrial lining starts to break down and eventually is shed from the rest of the womb causing a period bleed to occur. This happens on Day 1 of the next menstrual cycle and another cycle therefore begins.

But, if fertilisation does take place, the endometrial lining continues to develop. The lining is not shed and therefore no menstrual period takes place (a missed period). Women will obviously relate to this as a sign of pregnancy.
How does the Menstrual Cycle Work?

As has been discussed above, there are a number of hormonal changes that occur at puberty. A region deep within the brain called the Hypothalamus starts to secrete a hormone called Gonadotrophin Releasing Hormone (GnRH). GnRH stimulates a gland located at the base of the brain called the Pituitary Gland which in turn produces another hormone called Follicle Stimulating Hormone (FSH). The presence of FSH in the blood stream triggers the development of eggs in the ovary from follicles (egg sacs).

The follicles once triggered produce oestrogen which signals the pituitary gland to secrete another hormone called Luteinising Hormone (LH). It is the presence of LH that finally triggers the shedding of an egg from an ovary in the process called ovulation. This occurs at around Day 12-15 in the average 28 day cycle.

When the level of LH surges, only the ripest egg sac ruptures to release an egg. This egg then travels along a fallopian tube. If any sperm are present in the fallopian tube, fertilisation may occur. Eggs can be fertilised 12-24 hours after they are shed from the ovary. Sperm can survive inside a woman's reproductive tract for 12-48 hours. Fertilisation therefore does not have to occur immediately after sexual intercourse or ovulation but clearly fertilisation cannot occur in the absence of either.

Once ovulation has occurred, the egg sac remnant transforms into a small yellowish area on the ovary called the Corpus Luteum. This body is responsible for the production of the hormone progesterone which has the effect of increasing blood supply to the lining of the womb in preparation for implantation of the fertilised egg. This whole journey of the egg from ovary to womb takes approximately 5 days. During this time, the fertilised egg continues to undergo cell division and may consist of approximately 150 cells.

In a normal menstrual cycle when there is no fertilisation, the egg starts to degenerate and breakup. The corpus luteum on the ovary shrinks and degenerates also and progesterone levels fall dramatically. This leads to breakdown of the womb lining and contraction of the womb leading to expulsion of all these cells through the cervix and vagina. This causes menstruation which is the blood often called "a period".

This cyclical activity continues to occur in women until they reach the Menopause. At this time, no further eggs are available for ovulation. As a result, the cyclical hormonal activity stops and fertility levels reduce to zero. This winding down of the female reproductive system can take a long time; often women may have symptoms of menopause for a few months to a few years.

What Happens at Puberty in Men?

It is not only women who have dramatic physical and hormonal changes at puberty. Men undergo a similar process but naturally, with very different results. There is no natural cycle in men but an almost continual production of sperm. However, the hormones that control sperm production in men are the same hormones that control the menstrual cycle in women.

Once again, Gonadotrophin Releasing Hormone (GnRH) is released by the hypothalamus at puberty. This triggers the release of Follicle Stimulating Hormone (FSH) from the pituitary gland. FSH stimulates the production of sperm in the testes. At the same time, Luteinising Hormone (LH) is also triggered by GnRH in the pituitary gland. LH stimulates testosterone production in the testes.

The testes release immature sperm called spermatids. These travel through a long coiled tube called the epididymis which may be 40 feet in length. Spermatids mature inside the epididymis and this may take up to 70 days. On ejaculation, mature sperm travel along the vas deferens, through the prostate and other seminal glands where they are mixed with seminal fluid and forced through the penis.

When ejaculation occurs as many as 300 million sperm cells may be released. However, very few will survive the journey through the cervix, uterus and fallopian tubes. Eventually, one single sperm cell will burrow its way into an egg in the fallopian tube. This is fertilisation.

Causes of Infertility

The causes of infertility, or more often, subfertility are numerous and complex. Infertility is still thought of as a problem of the female reproductive system by many couples. However, while this may be true in some, often it is the male partner who has a problem. Less commonly, there may be a problem with both the male and female in the couple. Roughly speaking, problems with infertility in couples can be traced to the female in approximately 40% of cases, to the male in 40%, to both the male and female in 10% and remains unexplained in another 10% of cases.

The causes of infertility are therefore best divided into male and female.
Causes of Infertility in Women

1. Most commonly, reduced fertility in women is caused by problems with ovulation. Women may have menstrual cycles where no ovulation has occurred (anovulation or anovulatory cycles) or where ovulation occurs erratically. Sometimes, ovulation fails completely. Conditions where ovulation is at fault include;

Hormonal problems such as polycystic ovarian syndrome and many others,
Weight problems: either being over or underweight,
Aggressive exercise,
Ovarian cysts,
Medicines: side effects of many medicines such as pain killers and especially chemotherapy,
Radiation exposure: in cancer therapy or accidental exposure,
Exposure to other chemicals or toxins,
Genetic problems,
Emotional problems,
Early menopause.

2. Fertility problems may be caused by factors which affect the Fallopian Tubes. These include;

Endometriosis: a condition where the normal womb lining (endometrium) can appear in other places in the body. Most commonly, this can include any of the other pelvic organs such as the outer surface of the uterus, the ovary, the fallopian tubes or urinary bladder. But other organs including bowels and even lungs can be affected by this condition.
Infections such as sexually transmitted diseases: these include Chlamydia and gonorrhoea which can cause damage by scar tissue formation in the uterus or fallopian tubes. Infection with these organisms can lead to Pelvic Inflammatory Disease.
Uterine Fibroids which can compress or damage the fallopian tubes.
Ovarian Cysts
Surgery to any part of the female reproductive system.
Trauma

3. Infertility can also be linked with maternal age. Normal fertility levels fall sharply after women reach 35 years of age and fall very steeply after they reach 40 years.

4. Problems with other aspects of the reproductive system such as congenital malformations of the uterus or vagina. These can interfere with any aspect of pregnancy from sexual intercourse, travel of sperm up the female reproductive tract, to implantation.

5. Problems with the cervical mucous: during ovulation, the mucous should be conducive to sperm readily being transferred through the cervix and on into the uterus. But sometimes, the mucous is an inhospitable environment for sperm and most are killed. This may occur if the female produces anti-sperm antibodies.

6. Stress and anxiety: although this is slightly controversial, stress, tension and anxiety symptoms can cause problems with almost any aspect of falling pregnant.

7. Other co-existing medical problems; if poorly controlled or inadequately treated, many common chronic medical conditions can lead to problems with any aspect of pregnancy. Examples of such conditions include heart disease, diabetes, thyroid disorders and many more.
Causes of Infertility in Men

Infertility or reduced fertility in men is usually caused by some aspect of sperm production or transfer to the female partner. Sperm may be produced in inadequate numbers (oligozoospermia) or there may be a complete lack of sperm production (azoospermia). Even if normal quantities of sperm are produced, they may be poorly formed or shaped (poor morphology) or they may not swim well (poor motility). There may be a combination of any of these problems.

Causes of problems with sperm production and transfer include;

Hormonal problems: lack of testosterone or LH,
Sexually Transmitted Infections such as Chlamydia or gonorrhoea,
Other infections such as some viral infections can cause inflammation of the testes, e.g. mumps,
Medicines: side effects of many medicines such as chemotherapy,
Taking anabolic steroids,
Illegal drugs and other elicit substances such as cannabis and marijuana,
Exposure to other chemicals or toxins such as heavy metals,
Radiation exposure: in cancer therapy or accidental exposure,
Tumours of the testes as well as the treatment of these,
Heat: sperm are particularly sensitive to hot environments e.g. saunas, hot baths, wearing tight fitting underwear or trousers,
Varicoceles: these are similar to varicose veins in legs. Veins in the scrotum dilate and enlarge,
Congenital malformations of any aspect of the male reproductive tract including testicles and penis,
Impotence: this can stop the successful transfer of otherwise normal sperm into the vagina,
Emotional problems: this can cause impotence,
Surgery of the male reproductive tract for any cause,
Testicular damage from torsion of the testicle,
Retrograde ejaculation caused by prostate surgery and other causes. This causes ejaculation backwards into the urinary bladder instead of the penis,
Premature ejaculation: the sperm may not be transferred in adequate numbers to the vagina,
Trauma: may damage the testes or penis,
Non-descended or partially descended testes; testes usually develop in the lower abdomen and descend in the latter stages of pregnancies or after birth into the scrotum. If this process does not occur fertility can be reduced and the testes can be at greater risk of developing cancer.
Other co-existing medical problems; if poorly controlled or inadequately treated, many common chronic medical conditions can lead to problems with sperm production or transfer. Examples of such conditions include heart disease, diabetes, thyroid disorders and many more.
Overweight: this can affect the quality of the sperm and also cause difficulties with sexual intercourse.
Auto-immune disorders: in some instances, the body's own defence system attacks its own sperm,
Genetic disorders: such as Cystic Fibrosis and other chromosomal abnormalities can cause infertility.