Ukraine must dramatically raise its birth rate with an average three children per woman or face a deepening population crisis that could cripple the country’s future, a senior demographer has warned.

Russia was in demographic decline long before the war in Ukraine. Now it’s in free fall.

More than 6.9 million Ukrainians have fled the country since Russian forces rolled over the border almost 3 years ago. A further 1 million have left their jobs to fight. Ukraine has mobilized ...