There were no injuries to three-year-old Courtney Pieters' vaginal wall, defence pathologist Dr Segeran Naidoo told the Western Cape High Court on Monday.
"I can't see any erythema or inflammation. Whatever damage there is can easily be post-mortem," he said.
"It is more likely that it is post-mortem than ante-mortem."
Upon further questioning by defence attorney Mornay Calitz, Naidoo clarified: "If there were any injuries, it would be post-mortem injuries."
Courtney's decomposing body was discovered in Epping Industria in May last year, nine days after her disappearance from her Elsies River home.
Accused is a childhood friend of father
This evidence is critical for Mortimer Saunders, the man accused of the toddler's premeditated murder and rape, as he denies raping Courtney while she was alive.
In his plea explanation, he confessed to murder and to using his fingers to penetrate her after her death.
Saunders admitted to feeding the child ant poison to make her sick, before he choked and beat her. He then used a towel to cover her mouth.
The accused is a childhood friend of Courtney's father and lived in the same house as the family.
He claims that he hurt the toddler because he had "ill feelings" toward Courtney's mother, Juanita. He had apparently also been irritated on the day of the murder when the toddler wanted to watch TV in his room and he wanted to sleep.
In a report submitted by Naidoo to the defence, he found that the genital injuries were "in keeping with digital insertion".
On Monday, he explained that if insertion of the digits had occurred, there would be abrasions on the full circumference of the vagina.
Injuries may have happened before death
In the case of penile insertion, there would be abrasions on the rear of the vagina closer to the anus as it is the point of the greatest friction during sexual intercourse.
However, he pointed out that the court should keep in mind Courtney's age and the size of an adult penis as it may cause other vaginal tears.
Last month, Professor Johan Dempers testified that he could not conclusively say that the injuries to the little girl's genitals were caused by a penis, and that the semen found could have been transferred by other means, including by hand.
When asked if he could say whether she had been raped before she was killed, Dempers said he could not exclude that her injuries had happened before her death.
Calitz asked Naidoo whether the blood found on Courtney's shorts and top could be purge fluid that is released during decomposition.
Purge fluid is released through various orifices on the body including the mouth, nose, anus and vagina or penis.
The pathologist said it was possible that what was suspected to be discoloured blood on Courtney's clothing could be purge fluid.
The trial continues on Tuesday.