The spread betting group reported that revenues reached £81.5 million, down 18 percent from a year earlier.
IG noted that the comparative period of 2011, which was 30 percent ahead of the prior year, benefitted from extreme volatility in financial markets and short term spikes in client activity.
During the quarter, the "particularly quiet" financial markets impacted all areas of client activity including active client numbers, average revenue per client and the number of clients signing up.
The group added that the impact of the decline in revenues on pre-tax profits was partly offset by lower staff bonuses and subdued marketing activity.
Investors welcomed the update, sending shares in IG up 4.5 percent to 452.6 pence by 9am, valuing the group at £1.64 billion.
“The first quarter of any financial year is normally the lowest revenue quarter for IG, with the prior year an unusual exception to this,” IG said in a stock exchange statement this morning.
“The group continues to face tough comparatives at the start of the second quarter, with September 2011 the second highest revenue month in the history of the company.
“The group anticipates that revenue this year will, as in most years, be weighted towards the second half.”