Human rights lawyer and Nobel winner says authorities in Tehran want to push women back into the house and abandon progress.
Iran university course ban 'bid to curb female freedoms'
Educated young Iranian women were at the forefront of mass street protests ignited by President Mahmoud Ahmadinejad's disputed re-election three years ago.
But the Iranian authorities feared female activism well before that tumultuous summer, viewing their demands for equal rights as inseparable from the wider drive for greater democracy.
Little wonder, then, that many now see the recent decision by 36 leading Iranian universities to bar women from taking dozens of subjects next term as an attempt to undermine Iran's vibrant women's movement.
Others view it as an attempt to redress the balance of academic achievement between the sexes, which is heavily weighted in favour of Iran's female students.
For years, women in Iran's higher education system have outnumbered and outperformed men, a cause of pride for many ordinary Iranians.
University officials have justified their decision on practical grounds, pointing to high unemployment rates among women graduates in science-based subjects.
And some fields, such as mining and operating agricultural machinery, are now deemed too arduous for women, they say.
But, along with nuclear physics, banned fields of study - which vary from school to school - include English literature, archaeology and hotel management.
In an open letter to the United Nations, Shirin Ebadi, Iran's Nobel peace laureate, lambasted the restrictions as retrograde, declaring that they "demonstrate that the Iranian authorities cannot tolerate women's presence in the public arena".
Ms Ebadi, a human rights lawyer living in exile in Britain, added that Iran's leaders are trying to push women, "back into the house in the hope that they abandon their demands and leave the government alone to pursue its wrong policies".
Kamran Daneshjoo, Iran's minister of science and higher education, countered that some single- gender courses are now needed to create a "balance".
Brushing aside the controversy, he maintained that 90 per cent of degrees remain open to both sexes.
Politics apart, some analysts say that Iran's theocratic rulers are concerned by the social side-effects of rising educational standards among women, including declining birth and marriage rates.
Haleh Esfandiari, a US-based expert on women's issues in Iran, believes barring women from certain studies goes "hand-in-hand" with Iran's recent reversal of its highly successful family planning programme.
Iran's supreme leader, Ayatollah Ali Khamenei, called last month for married couples to have more babies as Iran's birth rate declines and its population ages.
Mr Ahmadinejad has yet to comment publicly on the university controversy. While politically hardline, he is branded a social liberal by his conservative opponents, although he has controversially urged women to marry at an earlier age.
Last year, he called a halt to plans by Mr Daneshjoo to segregate male and female students at Iranian universities, saying the proposal was "unscientific".
Previously, the populist Iranian president had unsuccessfully recommended that women be allowed to spectate at football matches, and he is seen as lax on the enforcement of the dress code for women.
Trying to jerk back the hands of Iran's social clock by banning women from many fields of study will backfire, Ms Esfandiari said.
"Women may now respond by pursuing higher education through the internet, which the government may have a harder time restricting", she wrote. And it "risks mobilising more women in future protests".