Japanese women are more likely to have a university degree than men, and the number of women in employment has been rising steadily for 10 years - but, for a range of reasons, a woman who has had children still has a hard time getting a good job.

Nobuko Ito is the very model of a modern professional Japanese woman.

She is a qualified lawyer and she speaks fluent English. She has years of experience working in international contract law.

But Nobuko no longer works in a big international law firm. The reason? She has three small children.

According to Japanese government statistics by far the biggest reason why Japanese women quit their jobs after childbirth is that Japanese "working hours make child care unfeasible".

"Before I had a child I remember one busy month where I billed the client for 300 hours!" Nobuko says.

Image caption Nobuko Ito says Japanese men fear losing their job if they take paternity leave

"I'd get in the office at 09:00 in the morning, and leave at 03:00 the next morning, and I'd come in on Saturday and Sunday.

"If you want to keep working you have to forget about your children, you have to just devote yourself to the company.

"I can't do this, it's impossible."

As Nobuko's example shows Japan's working culture can be brutal. It's one of the reasons why 70% of Japanese women still give up work as soon as they have their first child.

Another is their husbands.

When it comes to housework Japanese men are still far behind their counterparts in Europe or America.

In Sweden, Germany and the US husbands spend, on average, three hours a day helping out with children and household chores. In Japan it's one hour, and they spend just 15 minutes a day with their children.

The pay gap Many Japanese women still withdraw from the labour force upon childbirth and often cannot resume their regular employment pattern: in the dual Japanese labour market, women often end up in relatively lowly-paid non-regular employment. The gender pay gap at median earnings is the second highest in the OECD. OECD: Closing the Gender Gap (2012)

Then there is paternity leave. Japanese men are entitled to take it, but only a tiny minority actually do - just 2.63%, according to the Health and Welfare ministry.

"My husband didn't take paternity leave" Nobuko Ito says.

"Most Japanese men are very hesitant to use the system. They may want to come back home to help with the family, but on the other hand they think they need to work as hard as possible otherwise they may not get promoted, or they may lose their job."

Despite all this Nobuko, like many Japanese mums, wants to continue working. She now runs her own law practice from an office near her home.

But the next hurdle she and other Japanese mothers face is childcare, or rather the lack of it.

According to the Tokyo government's own statistics there are 20,000 children in the city waiting for places in day-care centres.

The government centres that do exist are good, but they are far too few. And even if you do get a place it's means-tested and can be expensive - around 70,000 Yen ($737, £484) per month for the first child.

Image caption Japanese fathers make a "limited" contribution to childcare, and do less housework than men from other developed countries, the OECD says

"I'd get a discount for having three children, but it would still be at least $1,000 a month even at the state nursery," says Nobuko Ito.

"At an expensive private nursery it can cost $2,000 a month per child. But those are really good!" she says laughing.

Kathy Matsui's Womenomics Japan's female employment rate of 60% still ranks well below that of many other developed countries such as Norway at 75%, the US at 66%, and Germany at 64%.

Roughly 70% of Japanese women quit working after giving birth to their first child. This compares to around one-third of women in the US.

The ratio of Japanese mothers with children under six who work (34%) remains extremely low compared to 76% in Sweden, 61% in the US, 55% in the UK, and 53% in Germany. Womenomics 3.0 (Goldman Sachs 2010)

All of this adds up to two things. Women who are having children are not working. Women who are working are not having children. Both are terrible for Japan's future.

In her ground-breaking work Womenomics: Japan's Hidden Asset, Japanese-American economist Kathy Matsui says getting more Japanese mothers to stay in work or go back to work should be a "national priority".

She says it could add as much as 15% to Japan's GDP.

But Matsui says there is another even more pressing reason. Japan is running out of people.

"Although a low fertility rate is common among other developed countries, Japan may be the only OECD nation where the number of pets exceeds the number of children," she says.

Japan's birth rate is just 1.37 births per woman, far below the 2.1 figure at which a population remains stable.

Evidence from Europe and America suggest helping women to stay in work can increase the birth rate.

More from the Magazine Each Swedish child is guaranteed a place at a public preschool and no parent is charged more than three per cent of their salary. The state subsidy for preschool services is more than the annual defence budget. Sweden's night nurseries

In countries like Sweden, Denmark and the US, where female employment rates are high, birth rates are also higher. In countries where female employment is low, like Italy, South Korea and Japan, birth rates are also low.

In Japan a demographic crisis is already under way. In 2006 Japan's population began to shrink.

If current trends persist it will lose a third of its population in the next half century.

Nothing like that has ever happened before.