TEHRAN – Iran is facing a steep decline in marriage and childbirth, with the average interval between a first and second child reaching six years and permanent singlehood rising sevenfold, the secretary of the National Population Headquarters said Monday, warning of accelerating demographic risks.
Speaking in an interview with Tasnim news agency, Marzieh Vahid Dastjerdi said Iran’s population challenge has intensified in recent decades as the country moves rapidly toward ageing, driven by lower marriage rates, delayed childbearing and long gaps between births.
Dastjerdi said the demographic shift, once expected to unfold gradually, has accelerated beyond earlier forecasts. 
“Even though only a few decades ago Iran was among the youngest societies, today changes in marriage patterns, lifestyle and cultural attitudes have brought birth rates to one of the lowest levels in our contemporary history,” she said. 
Last year, Iran’s annual births fell below one million for the first time. She said this transition could create serious economic and social pressures in the coming years, including a shrinking young workforce and rising health and welfare costs for an ageing population. 
“The demographic window currently open for Iran – with most of the population in working age – will not last long. Losing this opportunity means losing a historic chance for economic development and sustainable growth,” she said.
Dastjerdi noted that while Iran’s challenges mirror global trends, the pace of decline has been particularly sharp. 
“Across the world the view has emerged that marriage is not necessary. Individualistic attitudes have expanded; people want to grow independently, continue 
their education and secure better employment,” she said.
She added that lifestyle changes have reduced the acceptance of traditional family structures. “In the past, people married even without stable jobs or housing, often living with extended families. That model has faded over time,” she said. 
She noted that the number of countries below replacement fertility is expected to rise from about 90 today to nearly 130 in the near future.
According to Dastjerdi, Iran’s total fertility rate has fallen dramatically. “In the mid-1980s, around 1986–87, the average number of children per woman was 6.8. By 2024 this number has dropped to below 1.5,” she said, calling the shift a “serious decline with a steep downward slope.”
Marriage rates have followed a similar pattern. “Between 2011 and 2013, about 800,000 marriages were registered annually. In 2024 this figure fell to 480,000 – a 60 percent reduction,” she said. 
As marriage declines, she added, fertility naturally drops, while age at marriage increases and the time between marriage and the first child grows longer.
Dastjerdi said new data shows significant delays in childbearing. “The average marriage age for Iranian women is 24.5 years. The time between marriage and the first child is now about 4.5 years, and the gap between the first and second child has reached nearly six years,” she said.
She added that Iranian women have their first child at an average age of 27.5, and in Tehran this rises to about 30, reflecting the deeper demographic challenges facing large cities.
One of the most striking trends, Dastjerdi said, is the surge in permanent singlehood. “In 1986, only about 1.1 percent of women aged 50 had never married. In 2023, this number reached 7.7 percent – a sevenfold increase,” she said.
She warned that widening singlehood, falling marriage rates and declining births together form a “critical demographic picture” requiring policy attention.