The number of people getting married in England and Wales fell in 2013 for the first time since 2009, according to the Office for National Statistics (ONS).
There were 240,854 marriages in 2013, a drop of some 8.6% compared with 2012, the ONS said.
Elizabeth McLaren, ONS statistician, said the fall could be the continuation of the decline in marriages since 1972.
It could also be due to superstitious couples choosing to postpone to avoid the number 13, she said.
Religious ceremonies decreased by 14%, while civil ceremonies declined by 6% in 2013, compared with 2012.
Civil ceremonies accounted for 72% of all marriages in 2013.
Ms McLaren said that, unlike other milestones in life such as births and deaths, people have absolute control over when they tie the knot.
"When you have the freedom to choose there are probably certain dates you might avoid, like Friday 13th and that sort of thing," she said.
"It is going to be interesting to see whether this is part of a long-term decline or if it will change again."
Holly Tootill, a family lawyer with JMW Solicitors, agreed that superstition might have played a part in the decrease in the number of couples choosing to marry during 2013
"I personally know of several individuals who had consciously decided to marry a year later rather than risk going against the grain of superstition.
"In my experience, it's not unusual for luck, fortune and omens to feature in how couples divorce as well as wed although I have to say that such matters are generally not considered priorities for the majority of people choosing to spend the rest of their lives together."
Newlyweds are also continuing to get older, with men a mean age of 36.7 when they walk down the aisle and women are on average 34.3 years old.
And there has been a rise in marriages among pensioners, fuelled by women getting married in their later years.
In the decade since 2003 there has been a 33% increase in the marriage rate for women aged 65 and over, bucking the overall trend of decline.
The marriage rate for men aged 65 and over only rose by 2% over the same period.
Marriages of same sex couples first took place on 29 March 2014, so were not included in the statistics.