By Chioma Umeha, Taiwo Orebamjo
Infertility 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.
In Europe, Nigeria and other part of the world, approximately 85 per cent of couples will conceive within one year if they have regular unprotected sex. It is estimated that 20 per cent of couples will conceive within one month; 70 per cent will conceive within six months; 85 per cent will conceive within 12 months; 90 per cent will conceive within 18 months, while 95 per cent will conceive within 24 months.
Therefore, doctors will not usually diagnose a couple as infertile until 24 months have passed without conception and regular unprotected sex. Most people will see their general practitioner (GP) 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 per cent chance of conceiving over the subsequent 12 months if they continue trying.
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.
AGE – 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 40).
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 miscarriage.
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 count.
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 sperm.
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 conception.
Causes of infertility in women:
There are many possible causes of infertility. Unfortunately, in about one-third of cases no cause is ever identified.
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.
– PCOS (polycystic ovary syndrome) – the woman’s ovaries function abnormally. She also has abnormally high levels of androgen. About five per cent to 10 per cent of women of reproductive age are affected to some degree. Also called Stein-Leventhal syndrome.
– 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 may explain 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.
Problems in the uterus or fallopian tubes
The 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:
Surgery – 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 per cent to 40 per cent 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.