Last updated on 12 April 2021
Dr Kelly Loi, obstetrician and gynaecologist at Mount Elizabeth Hospital, gives us the facts regarding infertility and the options available to you if or when you have problems conceiving.
What causes infertility?
Fertility problems may arise due to problems in the female or the male reproductive system.
Each month, a group of eggs in your ovaries starts to grow in small, fluid-filled sacs called follicles. Eventually, ovulation occurs where one of the eggs erupts from the follicle and moves into the fallopian tube.
If a sperm makes its way into the fallopian tube and burrows into the egg, it fertilises the egg. Once fertilisation happens, the egg changes so that no other sperm can get into the fallopian tube.
The fertilised egg stays in the fallopian tube for about 3 – 4 days and then slowly moves through the fallopian tube to the uterus. It then attaches to the lining of the uterus in a process called implantation.
All the steps during ovulation, fertilisation and implantation need to happen correctly in order to get pregnant.
Causes of female infertility
Female infertility reasons can broadly be divided into ovulation disorders, endometriosis (where the lining of the uterus occurs outside its normal position) and tubal disease.
Ovulation disorders are conditions where ovulation occurs infrequently or not at all. This may be due to problems with the regulation of reproductive hormones or problems in the ovary, such as polycystic ovary syndrome (PCOS), which is the most common cause of female infertility.
Endometriosis occurs when tissue that normally grows in the uterus implants and grows in other locations. This extra tissue growth may block fallopian tubes and prevent fertilisation. Endometriosis can also disrupt implantation or cause damage to the sperm or egg.
If a woman managed to conceive previously but has problems conceiving again, she is said to have ‘secondary infertility’. In such cases, it is possible that a patient had an underlying health problem when she conceived before, but was fortunately not affected then.
In women, fertility steadily declines with age. Women are born with a fixed number of eggs. With increasing age, there is a fall in ovarian reserve ie. the number of functioning follicles or eggs left in the ovaries. In cases of early menopause, the eggs run out much sooner than usual.
Even the success rate of artificial reproductive treatment is not spared and pregnancy rates fall with increasing age from 40% in women under 35 years old to just 10% in women over 40 years old.
With increasing age, our general health also tends to decline. Existing conditions may worsen or new illnesses may develop, which can have an impact on fertility too.
There is a decline in quality of eggs with increased age and an increased risk of genetic abnormalities. This in turn results in an increased risk of miscarriage. Women under the age of 35 have about a 15% chance of miscarriage while women aged 35 – 45 have a 20 – 35% chance of miscarriage.
Uterine or cervical abnormalities
Abnormalities in the uterus or cervix can cause infertility by interfering with implantation or increasing the likelihood of a miscarriage. These abnormalities include benign polyps or tumours in the uterus, inflammation within the uterus, abnormalities in the uterus present from birth, such as an abnormally shaped uterus, and narrowing of the cervix.
Fallopian tube damage or blockage
Blocked fallopian tubes are a common cause of infertility. When this happens, an egg cannot be fertilised by a sperm. If only one fallopian tube is blocked, it is most likely that pregnancy can still happen. If both tubes are fully blocked, pregnancy without treatment will be impossible.
There are many factors that may cause fallopian tubes to be blocked, including pelvic inflammatory disease, endometriosis, certain sexually transmitted infections, fibroids and past abdominal surgery.
Early menopause is the condition where a woman stops having her periods before the age of 45. There are several known causes of early menopause, including genetics, lifestyle factors, such as long-term or regular smoking, chromosomal defects, autoimmune diseases such as thyroid disease and rheumatoid arthritis, as well as epilepsy.
Cancer treatments may affect fertility. Certain chemotherapy drugs, for example, can cause ovaries to stop releasing eggs and oestrogen. They may also permanently damage the ovaries. Radiation therapy near the abdomen, pelvis or spine may harm nearby reproductive organs, such as the ovaries. Another type of cancer treatment called hormone therapy can also disrupt the menstrual cycle, which may affect fertility.
Causes of male infertility
Male infertility can be caused by several factors.
These may include:
Abnormal sperm production or function
Sperm production or function may be abnormal due to a variety of issues, such as undescended testicles, genetic defects, health problems such as diabetes, or infections such as chlamydia, gonorrhoea, mumps or HIV.
Problems with the delivery of sperm
Sexual problems, such as premature ejaculation or certain genetic diseases, such as cystic fibrosis, may cause problems with sperm delivery. Additionally, blockage in the testicles or any damage or injury to the reproductive organs can also cause this issue.
Overexposure to certain environmental factors, such as pesticides, other chemicals and radiation, may affect sperm production. In addition, cigarette smoking, alcohol, marijuana, anabolic steroids, high blood pressure and depression also can affect fertility. Frequent exposure to heat, such as in saunas or hot tubs, can raise body temperature and may affect sperm production.
Cancer treatment, including radiation and chemotherapy may cause damages that impair sperm production.
What advice should be given to couples trying to conceive?
- Try to start planning for a family as early as possible
- Maintain a normal weight, exercise and eat a diet rich in fruits, vegetables and antioxidants
- Stop smoking – smoking impairs sperm quality and female smokers are 1.6 times more likely to be infertile
- Limit alcohol intake to 2 drinks per day
For the women:
- Limit coffee intake to one cup a day. High levels of caffeine are associated with decreased fertility and an increased risk of miscarriage
- Take folic acid to prevent certain birth defects
For the men:
- Wear loose-fitting undergarments
- Avoid extremely hot temperatures, such as hot tubs or saunas
- Use lubricants which are suitable for conceiving
Signs & symptoms of infertility
Early diagnosis and treatment of infertility is crucial in the successful management of a couple seeking infertility treatment.
Infertility is defined as the inability to conceive after 1 year of unprotected sexual intercourse. Ideally, the frequency of intercourse should be 2 – 3 times a week. Up to 90% of couples should have conceived by the end of the 1st year of trying. At this point, if they have still not conceived, further investigations are warranted.
Such couples should be referred to a fertility specialist after 6 months of trying to get pregnant.
In other cases where the likelihood of a gynaecological disorder may be high, the woman should also seek specialist advice sooner rather than later.
For example, an early referral is indicated if she has a history of amenorrhoea (no periods), oligomenorrhoea (infrequent periods), dysmenorrhoea (painful periods), pelvic inflammatory disease (PID), or previous surgery.
A history of menstrual irregularity could indicate an ovulation problem which would benefit from ovulation induction medication. Painful periods may indicate the presence of endometriosis, ovarian cysts or fibroids which may benefit from surgery to improve her fertility status. A history of pelvic inflammatory disease or previous pelvic surgery may cause tubal disease which would then require tubal surgery to unblock the tubes, or in-vitro fertilisation to bypass the tubal blockage.
How can infertility be treated?
Infertility can be treated depending on the cause.
- In the case of cysts, fibroids and blocked fallopian tubes: laparoscopic or keyhole surgery may help to improve chances.
- For problems related to abnormal ovulation: fertility drugs or injections may help to enable ovulation to occur in a more predictable manner.
- For poor sperm count and quality: intra-uterine insemination, or assisted reproductive techniques (ART) may be needed.
ART and in vitro fertilisation (IVF)
Artificial reproductive technology (ART) refers to the use of laboratory techniques to bring the egg and sperm together outside of the woman's body. ART may also be referred to as in vitro fertilisation (IVF). ART generally involves several treatment stages.
Firstly, in order to increase the number of eggs produced by her ovaries, the woman has to undergo hormonal injections.
Secondly, ultrasound scans and blood tests are needed to assess the growth and maturity of the eggs. Once the eggs are ready, they are retrieved with the help of a vaginal ultrasound while the woman is under anaesthesia.
The eggs are then fertilised with the sperm in the laboratory to form embryos before they are transferred back into the woman’s womb several days later.
Article contributed by Dr Kelly Loi, obstetrician and gynaecologist at Mount Elizabeth Hospital
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