Emerging market slump pushes Aberdeen H1 profits down by 40 pct

* H1 underlying pretax profit down 40 pct

* Revenues down 20 pct; interim dividend 7.5 p/share

* Shares (Berlin: DI6.BE - news) down 4.8 pct, leading FTSE mid-cap fallers (Adds detail from statement, share price reaction)

By Simon Jessop

LONDON, May 3 (Reuters) - British fund firm Aberdeen Asset Management posted a 40 percent fall in first-half underlying pretax profit, hit by a slump in emerging markets that it said would likely lead to further asset outflows.

A bellwether for investor sentiment to the highly volatile developing economies of Asia, Africa and Latin America, the firm has seen billions of pounds in assets flee its funds amid concerns around global growth.

The firm reported underlying pretax profits for the six months to end-March of 162.9 million pounds ($239.84 million) on revenue down 20 percent to 483.6 million pounds.

The heavy outflows pushed assets under management at the end of March down to 292.8 billion pounds from 330.6 billion.

"These results reflect challenging conditions Aberdeen has faced during past three years, in particular weakness in emerging markets," Martin Gilbert, Chief Executive of Aberdeen Asset Management, said in a statement.

While the impact of persistent asset outflows had been tempered by an emerging market rally in recent weeks and currency gains, the company said it remained vulnerable to further outflows over the next few quarters.

The scale of the fall combined with a still-weak outlook sent Aberdeen's shares lower at the open, and by 0707 GMT they were trading down 4.8 percent at 285.3 pence a share on Britain's mid-cap index.

Aberdeen said it would pay an interim dividend of 7.5 pence a share and planned to deliver 70 million pounds of annualised cost efficiencies during 2017.

($1 = 0.6792 pounds) (Reporting by Simon Jessop; editing by Sinead Cruise and Jason Neely)