Infertility is usually defined as the inability of a couple to achieve a pregnancy after being married and observing regular, unprotected sexual intercourse for 1 year. Infertility is a global phenomenon. While 10-15% of couples worldwide would experience some challenges in achieving a pregnancy, the figure in Nigeria is slightly higher at 20 -25 %. It is an established fact that despite observing this regular and unprotected sexual intercourse, only about 1 in 5 couples (20%) would achieve a pregnancy monthly. After 1 year about 85% of couples with no abnormality should conceive. It therefore means that about 15% of couples with no fertility issues would still not be pregnant.
The reason for this is the principle of natural selection. This entails that abnormal miniature babies (embryos) would be rejected by the womb because most eggs and sperms that form the embryos are abnormal; it therefore means that the chances of a perfect egg/sperm relationship are slim. Hence, the 15-20% natural conception rate monthly. The figures are lower in women above 35 years. The reason is simple. At the time a baby girl is about 5 months old in her mother’s womb, all the eggs (follicles) she would ever produce in her lifetime are already present in her ovaries. About 6 million eggs are present at this stage. When the baby girl is finally born, she has about 2 million eggs left. When she gets to puberty and starts experiencing menstruation, she now has about 400,000 eggs left. Every month she would normally “release” one egg (ovulation) but 1,000 are lost! At the beginning of each menses about 1,000 follicles begin the journey; releasing one egg therefore means that about 999 eggs are lost every month. By the time a woman crosses 35 years, there is a significant decline in the quality of the eggs. It is therefore a race against time and this explains why fertility experts would usually encourage women to complete their family size as soon as possible.
In most couples infertility management commences after about 1 year of marriage. This is not always the case as some couples would already be experiencing some difficulties with their reproductive career and therefore require earlier investigations and possible treatment. Examples are in women with menstrual irregularities, women above 35 years of age, men and women experiencing sexual dysfunction such as the man being impotent or the woman having an aversion for sex as a result of experiencing severe pains during intercourse.
There are numerous causes of infertility. While 20% of couples have unexplained infertility, the majority of such cases are due to factors that are difficult to assess using routine or conventional tests.
CAUSES OF INFERTILITY
Approximately 30-40% of infertility cases are caused by the male partner usually in the form of semen abnormalities. A male child unlike the female counterpart has no sperm cell in the testes until the child reaches puberty at approximately age 16 years. From that time onwards, it takes approximately three months for new sperms to be produced in the seminiferous tubules of the testes and finally moved to the region called epididymis for full maturation. During sexual intercourse, the sperms from the epididymis move through a narrow tunnel called the vas deferens where they are mixed with fluid from various glands such as the prostate gland and finally deposited in the vagina. Usually very motile sperms will swim up via the cervix (neck of the womb) and finally get to the fallopian tubes within five minutes of ejaculation. Most of the sperms will be lost as they will be expelled via the vagina with the seminal fluid. It is therefore perfectly normal to experience seminal fluid emanating from the vagina after sexual intercourse. It could also become ‘watery’ due to liquefaction, which is also normal.
Normal semen parameters include a sperm count of more than 20 million sperm cells per milliliter of semen. A motility of at least 50% with greater than 50% normal sperms is considered ideal. Sperms which find their way to the fallopian tubes remain viable for about 24-48hours. Therefore, if a woman ovulates within two days of sexual intercourse, it is still possible for there to be fertilization and hopefully pregnancy.
Specific causes of male infertility therefore include:
This can be caused by chromosomal disorders, cryporchidism (failure of the testes to descend into the scrotal sac at the time of birth), orchitis (infection of both testes), though rare but can be caused by mumps infection occurring after puberty, torsion (twisting of the testes, which can be very painful), physical and chemical agents such as pesticides, excessive heat, exposure to radiation, blockage of the ducts, which can be due to infections. Note that the infective agents are usually Chlamydia or Gonococcal. Staphylococcus aureus infection WILL NOT lead to infertility. Uncommonly male sexual dysfunction can lead to infertility.
After ovulation, fertilization commonly occurs in the fallopian tubes. Unlike the male counterpart all the female eggs are usually complete from about 20 weeks (5 months) of age while she is still a baby in her mother’s womb. At the time of puberty, only about 400,000 eggs are left. About 1000 eggs begin the journey for ovulation, of these only 15-20 are finally recruited each month but only one or two succeed.
Common causes of female infertility include:
Following ovulation, the fallopian tubes are expected to pick up the egg(s) and move it towards the centre of the uterus. It is within the fallopian tubes that fertilization take place between the sperm and egg. Any damage to the tubes therefore can result in failure of interaction between the sperms and eggs or failure of the fertilized egg to reach its destination in the uterus, giving rise to ectopic pregnancy. Tubal damage is commonly caused by infections (certainly not staphylococcus) which can be from sexually transmitted infection, abortion or poorly managed delivery process in an unhygienic environment.
Without ovulation, there can be no pregnancy. In developed countries ovulatory disorders constitute the commonest cause of infertility. Approximately 20% of women have polycystic ovaries on ultrasound scan. Many of these women experience normal menstrual cycles and therefore present with no symptoms. This group of women should have no problems conceiving. Another group of women have a more severe form of the condition, with irregular menses and hormonal imbalance. Such women might be obese and extremely hairy. While some will benefit from stimulation of the ovaries with drugs or laparoscopic ovarian drilling, others will require IVF.
This is said to occur when the tissue lining the inside of the uterus from where menses emanates, is found outside the uterus. Occasionally it can be found within the muscles of the uterus in which case it is called adenomyosis. Bleeding from these sites at the same time as normal menses can give rise to abdominal pains. It can also be responsible for pains experienced during intercourse.
Endometriosis can occur in the ovaries given rise to blood filled cysts (Endometrioma). Over time the blood becomes thicker and brownish in colour (chocolate cyst). Drug therapy is available but can give rise to masculinization of the woman. Surgical treatment is recommended in the presence of a chocolate cyst. This can be in the form of laparoscopic surgery (almost scarless surgery) which is available at Gynescope or open surgery. Endometriosis is associated with the presence of ‘toxins’ in the secretions surrounding the fallopian tubes. Eggs produced are exposed to these ‘toxins’ after being released from the ovaries. During IVF treatment, the eggs are extracted from the ovaries before they come in contact with this toxic pelvic secretion. It is for this reason that IVF is associated with a better outcome in terms of pregnancy. Pregnancy gives patients some temporary relief.