Anti-hijab activist Sepideh Rashno has been sentenced to six months' imprisonment in her latest case amid Iran's hardening hijab laws.

The young woman was denied a presence at her own trial in Tehran after announcing on social media that she would not wear hijab at the court.

She has also been fined 10 million Iranian rials in cash and banned from using Instagram for one year. Her current Instagram page was banned entirely.

It is the hijab rebel's second time in prison, first arrested in July last year after a video of her quarrel with a woman verbally assaulting her for being unveiled on public transport went viral, long before the national uprising of the Women, Life, Freedom movement.

She was later forced into a televised confession, clearly bruised, showing signs of torture. At the time, the US-based Human Rights Activists News Agency said she was taken to hospital with internal bleeding shortly after her arrest and before her appearance on television, when she was covered with her mandatory hijab.

She was released from Tehran’s Evin prison after about 40 days with a bail of what is believed to be $27,000, a huge sum for ordinary Iranians already forced into dire economic straits in a flagging economy.

The young writer and translator was initially convicted of "association and collusion with the intent of endangering national security" and "propaganda against the Islamic Republic," resulting in a five-year suspended prison sentence in December. However, she faced fresh charges of "promoting moral corruption" and "propaganda against the regime" after sharing a photo without hijab on social media.

Rashno revealed on Sunday through her Instagram account that the new sentence effectively ends the suspension of three years and seven months from her initial case. Consequently, she now faces a total of four years and one month of imprisonment.