IVF: Success rates of women under 30, over 35 revealed

IVF is a technique that helps people get pregnant. It involves fertilising a human egg with sperm in a laboratory and implanting the fertilised egg into the uterus.

People who may have fertility complications, same-sex couples, or individuals looking to conceive alone often choose IVF, but it doesn't guarantee conception and people can undergo multiple rounds of IVF to increase the chance of success. However, the costs of multiple IVF cycles can be prohibitive, and the chance of success differs across age groups.

New research from the University of New South Wales, funded by the Victorian Assisted Reproductive Treatment Authority (VARTA), paints a more complete picture of chance of success for women of different ages.

The researchers tracked thousands of Victorian women who started IVF in 2016 and followed them through to mid-2020.

They found women who started IVF before 30 had a 43 per cent chance of having a baby after one cycle of IVF, 59 per cent chance after two cycles, and 66 per cent chance after three cycles.

In other words, 66 per cent of women under 30 who underwent three or less cycles had a baby.

Another way of looking at it is, for women under 30, their first round of IVF had a 43 per cent success rate, their second round increased chance of conception by 16 percentage points, and a third round increased overall chance of success by a further 7 percentage points.

For women who started IVF at 35, there was a 40 per cent chance of a baby after one cycle, 54 per cent chance after two rounds, and 61 per cent after three rounds.

At 40, the results were considerably reduced: a 13 per cent chance of a baby after one round, 21 per cent after two rounds, and 25 per cent after three rounds.

IVF success rates aren't the same for every round. If it isn't successful in the first round, it is less likely to be successful in the second round, although overall chances of conception increase when both rounds are measured together.

VARTA chief executive Anna MacLeod says the research offers people a realistic expectation of what is possible with IVF and how long it might take.

"Knowing that most people need more than one stimulated cycle for a reasonable chance of success and that IVF births are less common the older you get is helpful for planning," she said.

This is especially important because IVF involves injecting hormones every day for two weeks to produce more eggs than usual, surgical removal of eggs, and laboratory labour costs. A single round can be strenuous on the body and can take up to 40 days or longer.

Additionally, a new IVF round should not be done two months in a row without a menstrual cycle in between them.

Beyond this, it costs about $5000 in out-of-pocket fees per round.

This figure could be higher depending on private health insurance coverage, consultation fees and additional treatments and 'add-ons'.

"If you want to have a child in future, learn more about your fertility and factors that can affect it so you can plan ahead. There are a lot of things you can do now to improve your chance of a healthy pregnancy and baby in future," says Dr Karin Hammarberg of VARTA.

She also notes that this data just represents averages of IVF success and age, but that there may be other factors that contribute to success. For example, if a woman in her late 30s or 40s received a donor egg from a younger woman, the chance of IVF success was the same as that of the younger donor's age group.

Over the life of the study, some women in the sample group also fell pregnant naturally and were excluded from calculations as they did not conceive via IVF.

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