Shares of companies making diapers, baby strollers and infant formula were getting a boost Friday from China's decision to scrap its decades-old one-child policy.

Investors are betting on a bump in sales for companies with baby or child-related businesses after China's Communist leaders announced that all married couples would be allowed to have two children.

One of the biggest winners was China Child Care Corp., which makes hair and skin care products for kids. Its shares ended 40 percent higher on the Hong Kong stock exchange, although its small market value likely made trading more volatile.

Hong Kong and mainland Chinese-listed formula makers also rose strongly, as did diaper makers in Japan.

However, Japanese condom maker Okamoto, a favorite of Chinese visitors to Japan, slumped 10 percent.