The testimony of a 71-year-old Frenchman accused of drugging his wife and recruiting dozens of strangers to rape her was postponed on Wednesday after the presiding judge accepted that he was still unwell.

Dominique Pelicot, the main defendant in a case that has shocked France, had been due to testify after a delay earlier this week when he was admitted to hospital.

Pelicot has been on trial since last week for repeatedly raping and enlisting strangers to abuse his heavily sedated wife in the couple's home over the course of a decade.

The presiding judge on Wednesday granted defence lawyer Beatrice Zavarro's demand that Pelicot, who appeared in court frail and leaning on a cane, again be excused.

Zavarro said her client was "still in a lot of pain" and not in a condition to withstand a full day hearing after starting to show symptoms of what could be a bladder infection on Friday.

Pelicot was sent back to jail for a medical assessment and it was not immediately clear when he would be in a condition to testify in court.

Prosecutors said Pelicot offered sex with his wife on a website and filmed the abuse. Fifty other men accused of taking part in the abuse are also on trial.

Zavarro has told French media Pelicot admits to his crimes. Some of the other defendants have admitted their guilt while others say they thought the wife had pretended to be asleep, according to French media.

They each face up to 20 years in jail if found guilty.