Iwaho Kikuchi will measure his success in the number of babies born in his city. Not this year, or next year necessarily, but in 10 or even 20 years’ time.

Kikuchi is the doctor in charge of a groundbreaking fertility initiative in Japan, in which public money will be used to pay for women to freeze eggs for use later in their life.

Under a three-year pilot scheme at Juntendo University Urayasu hospital, state funds are to be used for the first time – in Japan and possibly the world – to cover 80% of the cost of freezing eggs for local women aged between 25 and 34, who have the option of using them until they reach 45.

The women will pay only 100,000 yen (about £720) towards the procedure, including injections and medication, which usually costs 500,000-600,000 yen. Urayasu, a city east of Tokyo, plans to spend 90m yen on subsidies over the three years to March 2018 to preserve women’s eggs for use in future pregnancies.

“The idea is to keep donated eggs that can be used when the woman is older, and hopefully it will improve the pregnancy rate for women in that older age group,” says Kikuchi, a senior associate professor at the hospital.

With Japan’s low birthrate – currently 1.4 children per woman – unlikely to rise to the 2.1 level needed to ensure the stability of the country’s population, experts are predicting demographic meltdown.

A quarter of Japan’s population, which peaked at 128.1 million in 2008, is aged over 64, according to last year’s census, while the number of children under 15 is at a record low. On current trends, the overall population will drop to 86 million in 2060, with the proportion of people aged 65 or over reaching nearly 40% of the total.

The trend threatens to spark a crisis in health and social services for an older population dependent on a shrinking workforce, with the number of people in employment projected to fall by 7.9 million, or 12.4%, to 55.61 million by 2030.

Urayasu and other cities have tried several schemes to raise the birthrate, including matchmaking parties, bans on working late to leave time for procreation and shopping vouchers for bigger families.

Proponents of egg freezing cite evidence that Japanese women are marrying and having children later in life than ever before. “This is a huge problem for Japan, so freezing their eggs when they’re younger is a good idea,” says Kikuchi.

Japan is no stranger to fertility treatment. About 370,000 women undergo IVF every year, and the treatment is responsible for one in every 24 live births, putting Japan high up on the global success index.

But in women over 40, the rate is less than one in 10 live births – a dip that experts blame on a government policy, under which women lose their right to subsidised fertility treatment if their annual household income rises above 7.3m yen.

“Now that more women are working, they’re too busy to have children when they’re younger, and then suddenly they find that they are too old [and have too high an income] to receive government funding,” says Kikuchi.

Most of the 15 women who have signed up for the programme are in employment, and a third are married. About two-thirds decided to take part because they or their partner have health problems that could cause complications during pregnancy.

The rest were encouraged to take part by older female friends and colleagues who had taken part in egg-freezing schemes at private clinics.

Egg freezing is not a complicated procedure, but it is time-consuming. “It takes about 10 days, and a lot of women who work simply can’t take that amount of time off,” says Kikuchi.

Some experts point out that there are no guarantees it works. The Japan Society of Obstetrics and Gynaecology says the success rate is 17% when a woman is aged 35, and drops to below 1% once she reaches 45.

Urayasu’s mayor, Hideaki Matsuzaki, says the birthrate is so low that the scheme is necessary. “In general, pregnancy and childbirth is an individual issue. But when the situation has got to this point, I think using public money is the right thing to do.”

But Angel Petropanagos, a bioethicist at Dalhousie University in Canada, says Matsuzaki is naive to think the programme can avert a demographic crisis in Japan.

“It is a technological approach that benefits some women, not all. What’s really needed are social and structural changes to make it easier and preferable for women (and men) to have children and to do so when younger,” Petropanagos writes in an op-ed piece for the New Scientist.

The Urayasu initiative has also divided Japan’s medical community, with the gynaecology society among those who have cautioned against egg freezing as an option for women, regardless of their age.

The society said last year that women who undergo the procedure risk developing conditions such as hypertension, while not enough is known about the possible effects on the health of babies born from frozen eggs.

“Pregnancy and birth should be conducted at an appropriate age,” the society concluded in a study. “[Egg freezing] is not a technology that should be used in place of that.”

Kikuchi says the society’s stance is evidence of a form of sexism that is contributing to Japan’s low birthrate. “It sends out the message to working women that getting pregnant when they are older is something that won’t be tolerated,” he says.

The programme’s architects have set themselves a benchmark for success. “If, say, between six and 10 women out of 20 get pregnant, then you could say it’s been a great success,” Kikuchi says. “Of course, some of them might become pregnant without the egg freezing.”

The involvement of Urayasu authorities has given the programme a legitimacy that egg-freezing programmes run by private clinics lack, he says, adding: “Until now women in Japan have been made to feel guilty about their sexuality. Urayasu has made it clear that this is not just a decision by an individual, but a project that is supported by the community.”

Japanese media have touted the initiative as a possible panacea for population decline, but Kikuchi dismisses suggestions that his pilot programme could mark the start of a new baby boom, spearheaded by older couples. “It’s too late for what we’re doing to have that kind of impact,” he says. “I don’t think Japan’s birthrate will increase – it will take ages for that to happen.

“We need to do more to educate boys and girls about the optimal age to get pregnant, and when it becomes more difficult to get pregnant. At the moment we only teach them about sexually transmitted diseases and contraception.”

Despite his pessimism over the birthrate, Kikuchi believes the Urayasu programme could bring about a sea change in attitudes toward childbirth.

“Getting pregnant is an individual’s right, so if that person feels the need to go to the state for help, then the state should be in a position to help them,” he says. “I think this could be the catalyst we need for women to start thinking more positively about their sexuality and reproductive health.”