A divorced lesbian mother who wants to have another child with her new partner will be allowed to use some of the donor sperm she bought with her ex-wife, a B.C. judge has ruled.

The women, referred to only by their initials in court documents, purchased the "sperm straws" from a U.S. cryobank in 1999 for about $250 each, according to a B.C. Supreme Court decision.

The ex-wives each had a child by the same donor and after the 2007 break-up, the kids both went to live with their respective biological mothers. The women also wrote up a formal separation agreement dividing all of their assets, but they forgot to split up the remaining 13 straws filled with sperm from the same man.

When one of the women fell in love again a couple years later, she wrote to her ex and said that she and her new partner wanted to have another baby using the donor sperm so that all of the children would be related by blood. She said she'd pay full price for her share -- six-and-a-half straws.

The ex wrote back to say she'd rather have the sperm destroyed.

The new couple wasn't ready to give up and managed to track down another family that had used the same donor, but they learned there were no extra sperm straws left. When the couple called the sperm bank, they were told the donor was no longer on file.

With nowhere left to turn, the would-be parents filed a claim in court, arguing that the sperm should be treated as property and divided up just like any other asset during a divorce. The ex-wife, on the other hand, contended that the issue was a moral one, and the sperm should not be treated like property.

But Justice Loryl Russell ruled Monday that even though sperm has a different "emotional status" than a car or a home, it should be treated like property. She ordered the ex-wives to split the sperm equally.

"It has been purchased; the parties have a right to deal with it. They have made use of it to their benefit. The respondent's moral objections to the commercialization of reproduction or the commoditization of the body seem to me to be too late," Russell wrote.

The ex also attempted to argue that it was not in the "best interests" of the existing children to have another half brother or sister, and that it was "not in the best interests of any child to be conceived using the sperm."

But Russell said that argument was inappropriate.

"Hypothetically, if this case involved a male, A, and a female, B, B would not be able to stop A from fathering children with as many other females as he wished. The children conceived by the other females would all be half siblings of B's children. Yet, B would have no right based on the best interests of her children to restrict A's right to procreate," Russell wrote.

"For me to engage in any such analysis would be borderline discriminatory to couples, such as the parties, who must conceive through sperm donation."

The judge said that because there is an odd number of sperm straws, if one can't be split it half the couple that is trying to get pregnant should get the extra straw.