As a gynaecologist with a special interest in the field of fertility, the most common question I encounter during my daily clinical practice is: when does a couple need to come in for a fertility assessment?
Often, we encounter couples who knock on our doors three months after trying to have a baby. Many of them appear to be in distress, thinking that there is a major problem with their fertility.
Conversely, I have also encountered couples who remain childless for more than 10 to 15 years, only appearing at my doorstep at the age of 45 or more, hoping that the modern fertility treatment would overcome the odds and help them to achieve a pregnancy.
For this specific group of patients, the majority would say that they were not aware of the tests which can be done and the multiple fertility treatments available.
So where do we draw the line and achieve a balance between starting to investigate too early, and too late?
Pregnancy occurs when the egg meets the sperm and gets fertilised to form an embryo at the fallopian tube. The embryo then travels down through the fallopian tube to get implanted at the lining of the womb (endometrium).
Although this is a simplified version of explaining how pregnancy occurs, the actual process is a result of a complex combination of factors. Therefore, even when everything works perfectly, conception can take time.
A healthy woman under the age of 30 has about a 20 per cent chance to get pregnant each time she ovulates. About 80 per cent of couples can expect to conceive during the first year of trying to become pregnant.
However, after twelve months of trying, the chances of getting pregnant decreases with time. By the second year of trying, the chances of getting pregnant naturally drops down to 1-2 per cent per cycle.
It is also important to note that fertility declines with age. After the age of 35, women experience numerous physiological changes that contribute to a significant decline in fertility. This is partly due to a declining ovarian reserve, the quality of their eggs and changes in their hormones.
By the age of 40, there is a further sharp decline in fertility rate.
Subfertility is defined as the failure to achieve a successful pregnancy after twelve months of regular unprotected intercourse. However, if you are over 35 years of age and haven't got pregnant after trying for six months, you may want to check your fertility.
In a young couple, it is reasonable to seek medical evaluation and advice after twelve months of trying. However, if the female partner is over the age of 35, medical evaluation may be warranted after six months.
One in every six couples have problems in conceiving, but most can be overcome by simple measures such as changing their lifestyle, improving their nutrition and health, and timing the intercourse during the fertile period.
Common causes of subfertility
Most women (95 per cent) under the age of 35 who have regular menstrual cycles ovulate regularly. Some women who experience problems with hormonal imbalances may have a problem with ovulation.
If the body is not producing enough of a particular hormone or fails to release a particular hormone at the right time, ovulation does not occur. This is more apparent in women who have significant changes in weight in a short span of time, eg in anorexic patients
In some women with an inherited condition called Polycystic Ovary Syndrome, whereby there is an association with high levels of insulin and male hormones, ovulation does not occur regularly. This condition may be worsened when the woman puts on weight.
Fallopian tube problems
Fertilisation occurs at the fallopian tube and the embryo travels down and gets implanted into the lining of the womb. If the fallopian tubes are damaged or blocked, sperm cannot meet the eggs, and fertilisation does not occur.
Fallopian tubes may be damaged due to:
● Infections, particularly chlamydia infections, can cause tubal damage
● Previous ectopic pregnancy
● Endometriosis, a condition associated with the growth of cells originating from the lining of the womb (endometrium), which get deposited outside the womb
● Previous abdominal or pelvic surgery that causes scarring around the fallopian tubes
● Pelvic inflammatory diseases
Problems associated with the womb (uterus)
A fibroid or myoma, which is a benign growth in the uterus, can sometimes distort the lining of the womb and causes problems with implantation, and therefore causes subfertility.
Scarring of the lining of the womb, which may be caused by previous surgery such as Dilatation and Curettage (D&C), infections, or inflammation can potentially prevent implantation of the embryo.
In rare cases whereby there is a congenital abnormality in the shape of the uterus, implantation may be difficult, and sometimes there is a higher chance of miscarriage or pre-term delivery.
Problems associated with the immune system
In rare circumstances, some women develop antibodies which attack the embryo and inhibit implantation, causing miscarriage. This can be one of the causes of subfertility.
Subfertility in men
Up to 40 to 50 per cent of causes of subfertility are associated with male issues. Poor sperm quantity (oligospermia) and quality (poor motility or morphology) is associated with subfertility and can be identified by performing a semen analysis.
This test would also guide the doctor in making a decision on which fertility treatment would be appropriate for the couple.
In general, up to 25 per cent of couples will not find any causes for their subfertility after going through fertility testing. This group of patients is categorised as having unexplained fertility. This diagnosis can be frustrating as many of them would wonder: why is it they have not achieved a pregnancy given that all the test results had been normal?
The important thing to note is that even though all the tests are normal, it does not mean that there are no factors that prohibit them from having a baby naturally.
It is important to note that they have only had essential and simple fertility tests. These tests do not always assess function. For example, despite showing tubal patency through a dye test or a diagnostic laparoscopy, it does not ensure normal transport of eggs and sperm in tubes as there has not been a valid test for this.