Last summer, the FTSE 100-listed telecom giant acquired the operations of its competitor in Germany, the Czech Republic, Hungary and Romania for €18.4bn.
The new additions lifted revenue for the quarter to 31 December to €11.7bn, up 6.8% compared to the same period last year.
Group service revenue, which comprises ongoing network charges such as monthly packages and roaming fees, inched up 1% to €9.7bn.
Foreign exchange headwinds hit accounts by €100mln.
Guidance for performance for the year to March remained unchanged.
Richard Hunter from interactive investor said the long-term challenges such as competition remain but the steps the company is taking at the moment are "sustainable".
"There is still much damage to repair, since the shares have lost over 30% in the last two years, but for the moment the market is buying into the recovery story with the consensus of the shares as a strong buy remaining resolutely in place," he said.
Shares rose 2% to 153.8p on Wednesday morning.