UPDATE 3-Emerging market confidence boosts Reed, UBM

* UBM top 20 events 12-month forward bookings up 21 pct

* Reed's LexisNexis legal and professional returns to growth

* UBM shares up 2.3 percent, Reed up 0.4 percent

(Adds details from UBM conference call, new analyst comment)

By Georgina Prodhan

LONDON, April 19 (Reuters) - Professional media companies Reed Elsevier (REL.L)(ELSN.AS) and United Business Media (UBM.L) gave positive outlooks on Tuesday, bolstered by their trade fairs in emerging markets as business confidence returned.

Reed, which runs the world's biggest exhibitions business including last week's London Book Fair, said annual shows held in the first quarter averaged mid- to high-single-digit revenue growth rates, a trend it said it expected to continue.

It also said underlying sales at its legal and professional and risk divisions had returned to growth in the first quarter, helped by strong sales in the United States, although law firms, corporations and governments continued to spend cautiously.

"Although no actual numbers were reported and management state that expectations for the full year are the same as in February, the tone appears incrementally upbeat," UBS analyst Polo Tang wrote in a note.

UBM on Tuesday reported underlying first-quarter growth of 16 percent in events and said forward bookings for its top 20 events in the next 12 months were up 21 percent.

"We remain on track to meet our expectations for the full year," it said. UBM has forecast 2011 sales growth broadly in line with 2010, when its revenue grew by 5 percent.

NO SIGNIFICANT EFFECT

The earthquake in Japan had not had a significant effect on UBM's business, Chief Financial Officer Robert Gray told analysts on a conference call, as the company made less than 2 percent of group revenue there last year.

By 0811 GMT, Reed shares were up 0.4 percent to 537.5 pence, while UBM shares rose 2.3 percent to 585.5 pence, the second-top gainers in a 0.3 percent-stronger European media index .SXMP.

Reed shares had fallen 1 percent this year so far, broadly in line with the wider market, but UBM had fallen 20 percent since March 1, when the company said investments in its data, distribution and online businesses were squeezing margins.

"Events (60 percent of EBITA) continues to be strong and we remain firm supporters of this division, which accounts for three-quarters of our sum-of-the-parts valuation for UBM," brokerage Numis wrote in a note.

Reed said all its businesses had shown underlying revenue growth in the first quarter, excluding the effect of biennial shows not taking place this year.

As well as running events, the Anglo-Dutch company publishes academic and legal products -- its LexisNexis legal business competes with Thomson Reuters' (TRI.TO) Westlaw -- and sells data and analytics to insurance companies and governments.

"We expect in 2011 a gradual recovery and a continued improvement in performance," Reed said.

UBM reported 8 percent underlying sales growth to 238 million pounds ($386 million) for the first quarter and a 19 percent increase in adjusted operating profit to 44.6 million pounds, boosting its margin to 19 percent from 18 percent. (Editing by Erica Billingham and David Holmes) ($1=.6163 Pound)