Want three kids? This is the age a woman should start trying
Is this the case for you?
Fertility is a major issue for many couples and the common wisdom, whether right or wrong, is that the younger you are, the better your chances of conceiving.
Professor Mary Wingfield of Merrion Fertility has backed up the theory.
Speaking on Today with Sean O'Rourke on RTÉ Radio 1, she said that for women, "if you are 35, you have half the chance of getting pregnant as somebody who is 25."
She also said that anyone looking for a big family will have to start relatively early.
"If you want to have a 90 per cent chance of having three children, you need to start trying to get pregnant when you are 27."
Prospective dads have a slightly bigger window of fertility, but Mary confirmed that age is also a factor for them.
"Once men go over the age of 40, it reduces their fertility by about 50 per cent."
She said that while the statistics are stark, age is the main factor in fertility.
"Knowing your age is the most important thing. If you are 30, you need to start thinking about it very soon."
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