Pension fund performance deteriorated in the first quarter of 2018 at a time when members of auto-enrolment schemes were seeing their mandatory minimum contribution rates increase from 1 per cent to 3 per cent.
Data from Moneyfacts showed how after a run of positive gains in the previous nine quarters the average pension fund registered a loss for the first time since the third quarter of 2015, falling by 3.8 per cent.
Of the 36 Association of British Insurers pension fund sectors surveyed, only two (UK Direct Property and Money Market) avoided a fall.
The heaviest losses during the quarter were suffered by Commodity/Energy (minus 10.4 per cent), Global Property (minus 6.8 per cent) and UK All Companies (minus 6.1 per cent).
Only 7 per cent of all the pension funds surveyed produced growth during the period.
|Quarterly pension fund growth|
% pension fund growth
Source: Moneyfacts UK Personal Pension Trends Treasury Report/Lipper
Richard Eagling, head of pensions at Moneyfacts, said: "A major concern is how employees will react to seeing their minimum pension contributions triple.
"With signs of greater volatility returning to the investment markets it will be interesting to see if this dampens enthusiasm for saving into a personal pension or workplace pension, particularly given the higher minimum contribution rates that employees are now facing."
Keith Churchouse, director and Chartered financial planner of Guildford-based IFA Chapters Financial, said: "The first quarter of 2018 has seen significant volatility. However, markets are stabilising and most fund values have risen.
"We look after some auto-enrolment schemes, but have had minimal communications from people looking to opt-out, so are not convinced that people will be making changes.
"It (the lack of opt-outs) is a testament to how auto-enrolment has been communicated across the UK to reaffirm the importance of putting funds in place for the future."