Scientologists have rejected claims they forced a woman to have two abortions.
Canberra woman and former church member Janette Lang cried on Wednesday as she told reporters that Scientology bosses had coerced her and her partner to terminate her pregnancies.
Ms Lang appeared with Senator Nick Xenophon, whose effort to get an upper house inquiry into the tax-free status of religious groups, including Scientology, failed last week, when both Labor and the coalition voted against it.
The Senate on Thursday will vote on an inquiry with revised terms - looking at alleged abuse in the church, and whether criminal, consumer protection and occupational health and safety laws are adequate to deal with its practices.
In a statement, the Church of Scientology said it completely rejected the claims of forced abortion.
"The Church of Scientology considers the family unit and children to be of the utmost importance and does not condone nor force anyone to undertake any medical procedure whatsoever," said Church spokeswoman Virginia Stewart.
Ms Stewart said a Scientology friend of Ms Lang had reported that she had said she had had an abortion "and it was a decision between her and her husband alone because of troubles with their relationship".
Ms Stewart said allegations like Ms Lang's were very serious and should be reported to the police, not detailed to the media.
"We would co-operate fully with any investigation of persons allegedly involved," she said.