LONDON—Huntsworth shares fell almost 20% this morning on news that the group's first half results will be below market expectations.

The trading update comes ahead of the group's first-half results, which will be published in mid-August. It notes that the group's board is "reviewing the second half year and, while there is work to do, we believe that the second half will show improvement over the first half year."

In a separate announcement, Huntsworth noted that group chief operating officer and finance director Sally Withey is expected to return to work this autumn. Withey's ongoing medical absence was first revealed at the company's AGM in June.

At the same AGM, a shareholder revolt against CEO Lord Chadlington's pay saw almost 33% of investors vote against the company's future remuneration policy. More than 23% rejected last year's remuneration report. 

The rebellion came after successive years of stagnant growth at Huntsworth, including a dismal set of 2013 results.

Huntsworth owns several PR agencies, including Grayling, Citigate and Red Consultancy, along with healthcare business Huntsworth health.

The group's share price fell to 40p this morning after closing at 51.88p on Friday, before recovering to 42.50p. Over the past six months, the share price has dropped by more than 30%.