When a foetus starts developing in the uterus, it is very small and has a lot of room. It floats around…
What is fertility?
Fertility is the ability in both men and women to reproduce. In general, this requires sperm from a man to fertilise an egg from a woman. For this to occur, three events need to align - ovulation (the release of an egg from an ovary), free passage of the egg through the fallopian tube to the uterus and healthy sperm in the right place at the right time.
There are many different lifestyle factors and conditions that can affect a couple's ability to have children. It is well known that fertility declines naturally as we age, especially in women. You may also be able to increase your chances of becoming pregnant by maintaining a healthy body weight, avoiding smoking and alcohol and visiting your doctor for a check-up before trying for a baby.
For couples who have difficulty becoming pregnant naturally, there are many options available to improve fertility and help achieve a pregnancy.
Planning for pregnancy
Ovulation and pregnancy
Ovulation is the part of a woman's menstrual cycle that involves an egg being released from an ovary. Once the egg is released, it travels down the fallopian tube towards the uterus. To become fertilised, an egg needs to meet with sperm within 24 hours of being released. When this happens the fertilised egg is able to implant in the lining of the uterus, where it will develop into an embryo. This process is known as conception.
Around the time of ovulation, the lining of the uterus thickens to prepare for the possibility of receiving a fertilised egg. If fertilisation does not occur, this lining breaks down and passes out of the uterus through the vagina, together with the unfertilised egg. This shedding of the lining is a woman's period or menstruation.
Most women ovulate about once a month in response to a change in the balance of certain hormones in the body, usually around 14 days before the start of their period. When you are ready to start trying to have a baby, having unprotected sex around the time of ovulation will increase your chances of conceiving.
When planning to become pregnant, there are several steps that will help to ensure the best possible chance of conception and a healthy pregnancy. A doctor may recommend some of the following tests:
Factors that affect fertility in women
There are many lifestyle factors and conditions that can affect a woman's ability to get pregnant. Some of the most common factors include:
Age is one of the most important factors that affects a woman's ability to become pregnant. The fertility of both men and women declines naturally with age. For women, the chances of becoming pregnant starts to decrease after around 30 years of age.
Body mass index (BMI)
The body mass index (BMI) is an important factor that can affect fertility. A BMI is an estimate of your body fat based on your weight and height. An ideal BMI is between 18.5 and 25, indicating a healthy weight. Having a BMI that is too high or too low can interfere with regular ovulation, reducing the likelihood of becoming pregnant.
Research shows smoking can reduce fertility. It accelerates the loss of eggs from the ovaries and can also affect your ability to carry a pregnancy to term. Smoking during pregnancy can also affect the health of your baby and increase the chance of having a low birth weight baby or a premature birth.
Some of the common medical conditions that affect a woman's ability to get pregnant include:
Endometriosis is a common condition that affects women during their child-bearing years. It occurs when cells that normally line the uterus grow in areas outside it. The endometrial cells can grow on the ovaries, fallopian tubes and outer surface of the uterus and cause scar tissue to form.
Polycystic ovarian syndrome
Polycystic ovary syndrome (PCOS) is a long-term condition in women in which the levels of female sex hormones (oestrogen and progesterone) are unbalanced. This is associated with a range of health problems including irregular menstrual cycles and reduced fertility. PCOS is a common condition, affecting between 12-21% of women of reproductive age. It is estimated that around 70% of those affected do not know they have the condition. 
Pelvic inflammatory disease
Pelvic inflammatory disease (PID) is an infection that affects a woman's reproductive organs. It occurs most commonly when bacteria from an STI spreads from the vagina into the cervix, uterus, fallopian tubes, ovaries and the surrounding pelvic tissue.
Other conditions that can affect a woman's fertility include:
Factors that affect fertility in men
Male fertility is just as important as female fertility when it comes to conceiving a child. In order for fertilisation to occur naturally, there needs to be a large enough volume of healthy sperm ejaculated during intercourse. This can be affected by certain lifestyle factors including:
- Age - male fertility starts to decline around 40 years of age;
- BMI - a high BMI is associated with decreased reproductive function;
- Use of recreational drugs such as marijuana;
- Excessive alcohol consumption, and;
- Taking anabolic steroids.
There are also a number of physical factors that can affect male fertility. These include:
A couple may be investigated for fertility problems if they have been trying to get pregnant for more than one year without success. Couples that are unable to conceive a child naturally may be able to become pregnant with the help of assisted reproductive technologies (ARTs). Investigations into a couple's reproductive health will help to identify any medical issues that could be treated, allowing them to conceive naturally, or to identify the most suitable form of ART for their situation. In some cases, an exact cause of a couple's fertility problems cannot always be identified.
The first step in a couple's fertility assessment is usually a semen analysis, which is used to assess the quality and quantity of the man's sperm. A semen analysis includes an assessment of the sperm volume, pH and concentration, shape and structure of sperm and their ability to swim. For an accurate assessment, the semen has to be analysed within a couple hours of collection.
A woman's reproductive health can be investigated by using some of the following common procedures:
- Blood tests to measure the level of certain hormones important for ovulation;
- A pelvic ultrasound to assess the reproductive organs;
- Hysteroscopy or laparoscopy, which allow a direct visualisation of the reproductive organs to identify any abnormalities, and;
- A hysterosalpingogram or a hysterosonogram to assess the health of the fallopian tubes.
Assisted reproductive technologies
Assisted reproductive technologies (ARTs) are methods used to help couples have a baby when they cannot get pregnant naturally. There are many different types of ARTs available. Before starting any form of ART, it is important to try and identify any factors that could be affecting your fertility, as the type of ART needed will depend on the cause of the fertility problem. Some of the most common methods of ART include:
Artificial insemination is the process of inserting sperm into a woman's vagina or uterus. This type of ART may be chosen when a man has a low concentration of sperm, or if he has functional problems such as impotence or an ejaculation disorder.
In vitro fertilisation
In vitro fertilisation (IVF) is the process of fertilising a woman's eggs with sperm outside the body in a laboratory. This involves collecting a woman's eggs following an induction of ovulation (see ovulation induction, below) and a sample of sperm from a man. The eggs are fertilised with the sperm and once an embryo is formed, it is placed into the woman's uterus.
Ovulation induction is the process of stimulating a woman's ovaries to release eggs. This is usually done by giving a medication, either as a tablet or an injection, to stimulate the release of hormones that are important for ovulation. Ovulation induction may be used as part of an IVF cycle, or if a woman has a hormonal imbalance that prevents regular ovulation.