A crippling shortage of men in the country means young women do not have enough eligible grooms to choose from.
A survey carried out by the National Centre for Youth and published in the reformist daily Nassim Sabaon on Saturday, suggested that some 1.25 million Iranian women in their 20s are unlikely ever to get married.
The reason is the country's disproportionate gender population.
A survey suggested that some 1.25 million Iranian women in their 20s are unlikely to ever get married
Against 6.2 million women aged between 20 and 29 in Iran, there are just about 4.8 million men in the 25-34 age bracket.
Given the norm for Iranian men to marry younger women, the survey has concluded that up to 1.25 young women may stay lifelong spinsters.
Experts believe increased migration by men is one of the reasons behind the gender imbalance.
Another was the deaths of hundreds of thousands of Iranian men during the 1980-88 war with Iraq.