While measures are in place to lighten the burden of Singaporeans looking to juggle family and career, couples must realise that striking a balance between the two calls for a trade-off, said Prime Minister Lee Hsien Loong.

He gave this reality check to students at the annual Ho Rih Hwa Leadership in Asia lecture yesterday, when he was asked how young couples can face the daunting task of starting a family while pursuing a career.

"We would like you to be a supermum, but not everybody can be a supermum," he said. "And so we try to make it easier."

This includes making childcare affordable, giving out incentives like the Baby Bonus, and encouraging employers to welcome the family into the workplace.

But Singaporeans must face up to the reality that trade-offs must be made. Setting aside time for their children will mean time taken off work, said Mr Lee.

"At the end of the day, let's say (at) 70 years old, would you like to look back and say, 'I've been a super lawyer' or 'I had a good career, and I also have a good family... and I'm content. I have lived my life well'?"

He noted that in Scandinavian countries, people are "often content to have three-quarters of a career", working till 3pm or 4pm and then spending time with their children.

"We're not like that. But it's a balance, and these are the choices which we have to make ourselves," Mr Lee added.

Noting the benefits parents in Scandinavian countries receive, moderator Ho Kwon Ping asked if Singapore would consider such measures. In Sweden, parents get 480 days of leave when they have or adopt a child.

"Well, if you're prepared to have a GST (goods and services tax) of 20 per cent, I can imagine funding that," said Mr Lee to laughter. "It's up to you."

Beyond benefits, the society has a role to play in encouraging people to get married and start a family, he later noted.

"You do want to build a society where we have a chance for everybody to feel that he's respected and he has a valued place. You do not want to be a place where, if you are rich, you live in one little circle; if you are poor, you are cut out from that circle," said Mr Lee.

"We are all Singaporeans together... If we can do that... there'll be the social matrix, the basis by which people will say, 'Yes, I want to get married. I want to start a family'."