Maria Golovnina, the late Reuters news agency bureau chief for Afghanistan and Pakistan, had marks on her neck when her body was found in Islamabad earlier in February, according to a post-mortem.
The examination by Pakistan Institute of Medical Sciences (Pims) also concluded the 34-year-old journalist died of asphyxiation, Pakistan's Dawn newspaper reported.
But forensics did not directly link the three marks on Golovnina's neck to her death, saying the causes could not be immediately established. The report has been forwarded to police.
Golovnina was pronounced dead an Islamabad hospital where she was taken after falling unconscious at Reuter's bureau in the capital on 23 February, the agency said.
Local media reported she was found lying on a washroom's floor senseless and covered in vomit by colleagues.
Reuters described Golovnina, who had joined news giant in in Tokyo in 2001, as "a superb journalist with a long and varied career".
Before taking up her last position in 2013, she had worked in London, Singapore, Moscow, Afghanistan and Iraq.
Thomson Reuters, the parent company of Reuters, said in a statement run by the news agency: "We fully support Maria's family, the doctors and others who are reviewing her case, and will provide them any information we can."