ABOUT INFERTILITY

Many couples expect they will get pregnant the very first month they try - and are concerned when a pregnancy does not occur. All of us go through a brief interlude of doubt and concern when we do not achieve pregnancy the very first month we try - and we start wondering about our fertility.

Before worrying, remember that in a single menstrual cycle, the chance of a perfectly normal couple achieving a successful pregnancy is only about 25%, even if they have sex every single day. This is called their fecundity which describes their fertility potential. There are many reasons for this, including the fact that some eggs don't fertilize and some of the fertilized eggs don't grow well in the early developmental stage. It's impossible to predict when an individual couple will get pregnant. However, over a period of a year, the chance of a successful pregnancy is between 80 and 90%, so that 7 out of 8 couples will be pregnant within a year. These are the normal "fertile" couples - and the rest are "labeled" infertile - the medical text book definition of infertility being the inability to conceive even after trying for a year. Couples who have never had a child, are said to have "primary infertility", those who have become pregnant at least once but are unable to conceive again, are said to have "secondary infertility."

Ovulation dysfunction

This is the most common form of female infertility accounting for 25% of all occurrences. It can be divided into 3 main areas, annovulation (no ovulation), oligoovulation (rare or irregular ovulation) and post ovulation problems (usually due to an imbalance of progesterone which stops the endometrium becoming suitable to sustain pregnancy).

Ovulation dysfunction can be further split up into two sub groups.

• Primary, where the ovary is the problem. This can be due to damage by chemotherapy or radiotherapy, post operatively following removal of one or both ovaries or early menopause which affects 2% of women under the age of 40.
  
  
• Secondary, where the problem lies not in the ovaries but in the hormones and can be brought on by things like excessive weight loss or gain, stress and some drugs.

Tubal dysfunction

Occurring in 20% of cases, this can be due to scarring for a number of reasons.

• Infection, from a previous birth, miscarriage or abortion, or from STD's such as chlamydia, or Pelvic Inflammatory Disease (PID).
  
  
• Endometriosis, which can lead to adhesions and occasionally blockage in the fallopian tubes. This accounts for about 8% of infertility problems.
  
  
• Surgery, either for investigations, which can lead to adhesions and scarring, following an ectopic pregnancy or reversal of sterilisation.

Cervical Mucus Hostility

This is where sperm cannot travel through the cervical mucus. It occurs in about 1% of cases and is either due to the mucus being too thick, the mucus containing antibodies to the sperm or the sperm being abnormal.

Sperm dysfunction

Approximately 30% of all incidences are due to male infertility.

• No sperm. This accounts for 4% of male fertility problems.
  
  
• Low numbers of sperm, poor quality sperm or abnormal sperm. The main cause of male infertility accounting for 90% of cases.
  
  
• Defective sperm. 6% of cases, the sperm is unable to fertilise the egg due to a dysfunction.

Psychological/Physical factors

Almost 3% of infertility problems stem from either psychological or physical problems.

• Psychological problems include stress after trying unsuccessfully for a length of time to get pregnant, depression, work or financial worries, previous sexual abuse or rape.
  
  
• Physical problems include premature ejaculation, diabetes, heavy smoking and/or drinking or impotence.

Unexplained

Approximately 5% of cases remain without an explanation despite exhaustive tests on both the man and woman.

Only a small number of people are totally infertile. The majority are sub-fertile, which means that a pregnancy can be achieved even though assistance may sometimes be required.