The post mortem report suggested that she was four-month pregnant and she died of strangulation, they said.
They also stated that Delhi police had contacted them saying that a woman resembling the deceased was missing from their city and she might be the same person.
The body of the woman, aged between 24 years and 26 years, with semen stains on her private parts, was recovered from a suitcase that was abandoned by a man at around 1.30 AM on platform number one at Sandhurst Road railway station of Central Railway yesterday.
"The post mortem report suggested she was four-month pregnant. She died of strangulation. She also had sexual intercourse before her murder which indicates that she might have been raped but only after the arrest things would be clear," said Additional Director General (Railways) Raj Khilnani.
The CCTV installed at the platform was at some other direction because of which it could not capture the movement of the accused, who had abandoned the suitcase, he said adding, "Nobody was arrested so far."
In a similar incident, body of a woman was found in an abandoned suitcase at Juhu beach last week. Nobody has been arrested so far for that murder as well.
On the reports of serial killer being involved in the incidents, Khilnani said, "Unless and until the accused is caught, we cannot come to a conclusion that it was a handi-work of a single person."