The British mother detained in Tehran feels a “strong sense of trepidation” ahead of embarking on a hunger strike after being denied health care, her husband has said.

Nazanin Zaghari-Ratcliffe will strike for three days starting this week with Narges Mohammadi, an Iranian human rights defender who is also behind bars in Evin prison.

She has suffered a catalogue of mental and physical health complaints since she was arrested at Tehran’s Imam Khomeini airport on April 3 2016.

Speaking to the Observer, her husband Richard, said: “We know a hunger strike has significant physical consequences the longer it goes on for and Nazanin is feeling a strong sense of trepidation.

“But there aren’t many ways she can say, ‘Enough is enough. Take me seriously’.”

Zaghari-Ratcliffe will consider extending the hunger strike – a protest after being denied medical care in prison – if her demands to see a doctor are not met, the Press Association reports.

He said his wife was having medical treatment blocked for checking lumps in her breasts, neurological care over her neck pains and numbness in her arms and legs, and for seeing an outside psychiatrist.

Zaghari-Ratcliffe, of Hampstead in north London, was sentenced to five years in jail after being accused of spying, a charge she strongly denies.

She spent her 40th birthday on Boxing Day in prison, where she has been detained for more than 1,000 

Richard told HuffPost UK the milestone birthday has “loomed large for her in recent months – partly for the landmark of not wanting to turn 40 alone in a prison cell, still denied watching her baby grow up, but increasingly wondering whether they will keep her so long that she is also denied having a second child.”

Ratcliffe was able to speak to his wife on Christmas Day, reporting she sounded “flat”, but informing him that the women prisoners had held midnight Christmas prayers for the French and British prisoners, with some other religious minorities also joining.   

The charity worker’s four-year-old daughter Gabriella has been staying with family in Iran since Zaghari-Ratcliffe, who works for the Thomson Reuters Foundation, was detained.

Her husband Richard Ratcliffe has mounted a high-profile campaign for his wife’s release.