Female age is one infertility factor that IVF clinics can do little to combat without resorting to using donor eggs. In nearly 20 years, Sydney IVF has not had a live birth from a patient over 45 using her own eggs.

Why is age so important?

There are several reasons why live births become rare as women move through the age of 40:

• The chance of experiencing some fertility decreasing conditions, such as endometriosis or fibroids increases with age.
• It is recognised that the occurrence of abnormal fetuses is much higher among older women. One of the best known is the chromosomal abnormality that results in Down syndrome, you'll find more information on the subject below. Chromosomal abnormalities are major contributors in the increased rate of miscarriage among older women.
• All the energy required for an embryo to keep dividing and growing comes from the egg, in little packets called mitochondria. As women get older, their eggs contain fewer and fewer healthy mitochondria, and have less energy available. The fetus will produce its own mitochondria once it reaches a certain point in its development, but if there is not enough energy to reach that point, development will stall, resulting in failure to fertilise, failure to implant, failure to divide, or early miscarriage.
• If periods are absent or irregular, ovulation (release of eggs from the ovaries) is often absent or irregular too. An absence of ovulation will result in complete infertility. Ovulation can be corrected in some patients with hormones or drugs. If there are no eggs in the ovaries that respond to drug treatment, the only solution for pregnancy is to use donated eggs or embryos.
• An obstruction between the vagina and the ovary. The most common site of obstruction is the fallopian tubes, and it will prevent fertilisation, even when sperm production and ovulation are normal. Blocked fallopian tubes can be treated with microsurgery, or otherwise with assisted conception.
• Endometriosis. This is a common condition where tissue like the lining of the uterus (the endometrium) is found in places outside the uterus. Its presence can hamper a number of events important to conception and implantation of the embryo in the uterus, resulting in subfertility. Treatment can be with drugs, with surgery, or with assisted conception.

The age factor

As you can see from the graph below, by age 36 a normal woman's chance of conceiving per month is decreased by half. The downward slope continues until by age 45 the average natural fertility rate per month is approximately 1%.

Am I too old?

Of course, these are average figures. Some women's fertility will drop off earlier, others will be fertile well into their forties.

Sydney IVF does not discriminate on the basis of age. When a woman comes to us for treatment, we will make sure that they are aware of the average chance of success for women in their age group, as well as the chance of miscarriage and genetic abnormality. Then we will respect their decision as to whether they would like to have treatment or not.