A Victorian man sexually abused his surrogate twin daughters.

Trigger warning: This post contains issues of sexual abuse and may be triggering for some readers.

After paying $44,000 to have twin girls conceived in Asia via surrogacy, a Victorian man has plead guilty to the repeated sexual assault of his daughters in court this week.

He also plead guilty to the sexual abuse of his nieces, who live in New South Wales.

The court heard that after the 49-year-old began abusing his nieces in 2009, his desire to have children of his own grew. After discovering that he and his wife were unable to conceive naturally, the couple investigated surrogacy options in Asia, and their twin daughters were born in 2014.

The man, who posted details of his abuse online under the alias “Candy”, described the way he drugged his children and sexually abused them in various child abuse forums.

The abuse began when his daughters were just 27-days-old, and continued for seven months.

The abuse began when the girls were just 27-days-old.

According to the Australian Federal Police, the man produced "some of the most depraved exploitation material" they had ever seen.

Altogether, he plead guilty to 37 charges, including filming up women's skirts on trains and creating upwards of 17,000 videos of child abuse - almost 300 of which featured his own daughters.

The man is set to become the second person in history to be convicted under Australian child trafficking laws.

There is no indication that his wife was aware of or complicit in the abuse, and the young girls have been removed to the care of the Department of Health and Human Services.

The case raises questions about international surrogacy laws, which are currently under investigation by a Federal parliamentary committee.

Watch: An Australian couple struggle to bring their surrogate child home from Nepal.

Video via Channel 10
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