Starting a family is a dream for many couples, but sometimes balancing a career with home life while aiming for other life goals can be difficult. This leads some couples to brush baby-making plans aside.

So, just how soon should couples start trying to build a family of their own? According to researchers, that's determined by how many children are wanted, and if couples are open to giving in vitro fertilization a shot.

In a study published in the journal Human Reproduction, researchers showed that a woman's age greatly factors in the age at which a couple should begin trying to conceive because fertility declines with age, particularly for women. Sperm quality also declines as a man ages, but the change occurs much later after the age of 60.

Based on the results of the study, couples who want to have at least one child and want a 90 percent chance of succeeding without using IVF should begin aiming to get pregnant before a woman is 32 years old. If a couple wants to have two children without relying on IVF, the age limit drops to 27 years old.

However, if a couple has no qualms using IVF or is willing to accept lower chances of success, they can begin trying to get pregnant years later than the limits mentioned above. In some cases, it is even possible for couples to try 10 or more years later.

For the study, Dik Habbema and colleagues designed a computer model to simulate 10,000 couples trying to get pregnant, taking into account their chances within a given month, the likelihood of a pregnancy being lost, the possibility that a couple will have fertility problems, and whether IVF will be used.

The researchers said that misconceptions regarding how age has an effect on fertility are rampant. In fact, surveys show that a lot of young people look at the likelihood that they will conceive after 35 years old too positively. The results of the study should be able to help frame public awareness properly so that a better understanding of the possibilities and limitations surrounding human reproduction will be achieved.

Aside from Habbema, other authors of the study include Egbert te Velde, Henri Leridon, and Marinus Eijkemans. The researchers were from the Erasmus University Medical Center, the University Medical Center Utrecht and the Institut National d'Etudes Démographique.

Photo: Jeff Golden | Flickr