In Kenya, for example, as a result of diminished financial support for family planning and increasing fertility, the country's projected population in 2050 is set to reach 83m, from 54m.

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If Russia continues to make progress in reducing mortality and if not increasing fertility then at least preventing it from declining, it will likely be able to maintain its current population.

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And while the extra water from the melting glacier may be increasing the fertility of adjacent lowland areas in the short-term, water supplies would become critically low if it disappears.

UNESCO: 83e

Management is proposing to provide 2% salary increases to most employees, reduce employer contributions to the retirement plan and change the health-care plan, including increasing deductibles and eliminating unlimited coverage of fertility treatments.

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Increasing wealth brings with it falls in fertility.

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The researchers say their findings are not conclusive but suggest that men who want to improve their fertility might want to look at increasing the amount of physical exercise they do if they currently do little.

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