The head of a top Nigerian cancer clinic has been sentenced to life in prison for raping his wife's teenage niece.

Dr Olufemi Olaleye sexually assaulted the girl for more than a year until his wife found out and informed the police, the prosecutor said.

The doctor had pleaded not guilty during the trial.

But a judge in a Lagos court said he found the evidence against the doctor compelling and rejected his plea.

Olaleye is the head of the Optimal Cancer Care Foundation, which offers free breast and cervical cancer screening for women.

He was arraigned in November last year on two counts of rape between December 2019 and July 2022, when the girl went to live with their family.

During the trial, the doctor's wife, Aderemi Olaleye, said she discovered the abuse after the girl told her aunt and the family's driver.

The girl, now aged 18, said the doctor had been sleeping with her and had threatened to kill her if she told anyone, the doctor's wife said.

He was also accused of forcing her to watch pornography.

Six witnesses - the girl, the defendant's wife, a medical doctor, a child-care expert and two police officers involved in the investigations - testified in the trial.

The doctor also testified in his own defence alongside his forensic physician who faulted the medical evidence presented by the prosecution.

But while delivering the judgement on Tuesday, Justice Rahman Oshodi said the evidence presented before the court "greatly implicates" the defendant.

Justice Oshodi described Olaleye as a "dangerous" offender who did not show any sign of remorse.

According to the judge, Olaleye's earlier confession to the police proved that he had committed the offences.

The judge rejected the arguments by the doctor's legal team that the girl was tutored by the defendant's wife to lie against him as part of a scheme to take over his property.

"I, therefore, find the defendant guilty as charged," the judge ruled.

"This charge has a mandatory sentence of life imprisonment," he said.

In his plea for leniency, the doctor's lawyer, Adebisi Oridate, asked the state to recognise Olaleye's services as a cancer doctor and that he was a first-time offender.

But the judge dismissed the plea and said that Olaleye must be confined to the prison for a long period of time as proof that Nigeria's justice system frowned on sexual violence.

He also ordered the name of the doctor to be added to the Lagos State sex offenders register.

It is not clear if the doctor will appeal against the sentence.