* SSEC +0.29%, CSI300 +0.38%, HSI flat * Consumer, healthcare firms boost broader index * China leaves lending benchmark steady for 12th month SHANGHAI, April 20 (Reuters) - China shares rose on Tuesday after the country kept its lending benchmark steady for a twelfth straight month, helping to ease persistent investor concerns over the impact of possible policy tightening. ** China kept its benchmark lending rate for corporate and household loans steady for the 12th straight month at its April fixing on Tuesday, matching market expectations. ** The flat loan prime rate fixing followed first quarter GDP figures that came in slightly below market forecasts, supporting investor expectations that authorities will leave policy unchanged for the time being. ** At the midday break, the Shanghai Composite index was up 0.29% at 3,487.60 points. ** China’s blue-chip CSI300 index was up 0.38%, after posting its best session in more than five weeks on Monday. ** Gains were driven by the consumer staples sector , which jumped 2.14%, and healthcare shares , which rose 0.75%. The CSI new energy vehicles index , which drove Monday’s gains, added 0.74%. ** Refinitiv data showed small net outflows through the Stock Connect scheme as foreign investors sold shares. ** Chinese regulators are closely monitoring flows of foreign capital in and out of the country, government officials said on Monday, as overseas interest in Chinese equities grows. ** Chinese H-shares listed in Hong Kong fell 0.1% to 11,081.43, while the Hang Seng Index was unchanged at 29,105.73. ** The smaller Shenzhen index was up 0.57%, the start-up board ChiNext Composite index was higher by 0.67% and Shanghai’s tech-focused STAR50 index was down 0.14%. ** Around the region, MSCI’s Asia ex-Japan stock index was firmer by 0.32%, while Japan’s Nikkei index was down 1.93%. ** The yuan was quoted at 6.4959 per U.S. dollar, 0.23% firmer than the previous close of 6.511. ** As of 04:03 GMT, China’s A-shares were trading at a premium of 32.77% over the Hong Kong-listed H-shares. (Reporting by Andrew Galbraith; Editing by Shailesh Kuber)