Age is a very important factor when it comes to conceiving a child, particularly for women. But a study conducted in Australia suggests a majority of young people may be underestimating its impact.

The findings of the new study were published in the journal Human Fertility on July 30.

More than 1,200 university students were recruited for the survey which questioned them about their future plans with regards to parenthood and also examined their knowledge on fertility.

For a woman, fertility significantly starts to decline during the late 30s. The chance of getting pregnant in any monthly cycle is around 25-30 percent during her 20s but reduces to just 5 percent by the age of 40. Male fertility, on the other hand, starts falling when a man is in his mid-40s.

In the survey, less than half of the respondents could correctly identify these ages. According to the findings, 38 percent of men and 45 percent of women correctly identified when female fertility declines. But only 18.3 percent of men and 16.9 percent of women correctly identified when male fertility declines.

It was found many university students did have a desire to become parents someday, said Dr. Eugénie Prior, lead researcher from the Victorian Assisted Reproductive Treatment Authority in Melbourne.

"However, most also have an unrealistic expectation of what they will achieve prior to conception, whether that be in their career or financially," Dr. Prior explained. "We need to educate young people about the limits of fertility and support them to become parents at a point that is ideal biologically, while balanced against the life goals they want to achieve."

Lesser than 10 percent of respondents said they had no desire to have children. Among those who did want children, 75 percent expressed a desire to have two or more.

Generally, it is known millennials have been delaying parenthood when compared to previous generations. In the United States, figures from a 2017 report indicated an interesting trend: For the first time, the number of women having children in their 30s overtook the number of women having children in their 20s.

Nevertheless, the authors explained it was important for young people to be more informed about the biological limits of fertility so they can effectively balance their personal life goals, career goals, educational aspirations, and achieve parenthood at the right time.