The proportion of children in Russia's population has shrunk by nearly a third since 1995 and is not expected to rebound any time soon, demographers said.

President Dmitry Medvedev last week touted the end of a 15-year drop in the country's overall population, but the decline in children raises the specter of future demographic problems.

The number of children under 18 has fallen to 26.5 million now from 38 million in 1995 and 33.5 million in 2000, according to a new report by UNICEF and the State Statistics Service.

"For historical and demographic reasons, the child population in Russia decreased by approximately 12 million over the last 13 years. This is an average of 1 million each year," said Bertrand Bainvel, UNICEF's representative in Russia.

"This in itself poses important development challenges, and optimizing the investment in childhood makes it even more important and urgent for the country," he told The Moscow Times.

The country's overall population has shrunk by 6 million since the Soviet collapse in 1991 because of economic hardship, rampant alcoholism and other factors.

"There were a lot of babies born in the 1980s but few in the 1990s, and now we can see the result of the decline," said Anatoly Vishnevsky, head of the Demography Institute at the Higher School of Economics.

"Later the birth rate started to increase, but not by much," he added.

Since the number of children is now low, the birth rate will not be able to increase for the next two decades, he said.

"The number of children might increase, but not significantly," Vishnevsky said, adding that there will not be enough women for reproduction.

Last week, Health and Social Development Minister Tatyana Golikova warned that a host of negative factors needed to be tackled — including a looming drop in women in their fertile years and sky-high abortion rates — to overturn the country's overall demographic decline.

Golikova told Medvedev that preliminary statistics for last year showed that the country's population of 141.9 million had either remained stable or increased by 15,000 to 25,000 people.

Babies are also sicklier now than in 1996, the UNICEF report said. The percentage of babies born sick or who fell sick soon after birth reached 37.3 percent in 2008, compared with 28.5 percent in 1995, the report said. The most widespread children's illnesses were those that affected their respiratory systems.