The tight restrictions have sent many French abroad — single women and men, and gay and straight couples who fear their time is running out. Many go to Belgium or Spain. Fearing social stigma, few talk about it when they return home pregnant.
Hundreds of thousands of protesters on both sides have swamped the streets of Paris. This week, as the parliamentary debate began, opponents of gay marriage and changes to the law governing fertility treatment strung banners over the bridges that cross the Seine, including one that read "Everyone is born from a man and a woman."
Hollande had clearly hoped to put off a national debate on assisted reproduction: "Had I been in favor, I would have included it in the proposed law," he said in December as renegade lawmakers from his Socialist Party tried to take up the issue.
The president has let Taubira do most of the talking — and take most of the heat. It's her name that is linked to the tensions that have been growing in France as both sides line up allies.
For those who support easier access to assisted reproduction, the link to gay marriage was inevitable — especially in a country where the word "equality" is enshrined in the national motto.
"As soon as you start discussing same-sex marriage, then you know this is going to come up," said Guido Pennings, a professor of bioethics at Belgium's Ghent University who conducted a 2010 survey on what he described as "reproductive tourism" in Europe.
Pennings said women from Italy, France, Germany and Norway — all relatively restrictive countries when it comes to fertility treatments — were most likely to cite "legal reasons" for going abroad. Four in 10 of the French women who responded to the survey described themselves as gay or bisexual.
He said governments should be asking themselves: "Do I treat my own citizens correctly when I force them to go elsewhere?"
Isabelle Chandler, spokeswoman for the French infertility group MAIA, said French women are being driven away by the strict criteria and a lack of financial support. Chandler, who like many French draws the line at surrogacy, said her organization is willing to advise any woman who wants fertility treatment, whether or not she's in a relationship.
For both men and women donors, anonymity is strictly required — another aspect of fertility treatment that sends French couples abroad, according to some activists.
"Lawmakers think about couples, they think about donors, but they don't think about children," said Audrey Gavin, a lawyer who is president of an organization that advocates for non-anonymous donation. She hoped that the debate on gay marriage might open minds to reconsider France's entire approach to fertility treatment.
Olivier Dussopt, a Socialist lawmaker who was among the group to first attempt to relax the laws governing fertility treatments, said he thinks France will come around to his way of thinking for assisted reproduction, although he said surrogacy remained completely off the table "for both the right and the left."
Dussopt compared the current debate to the bitter period leading up to the decision to legalize abortion in 1975. Now, he said, abortion is essentially a non-issue in France.
"There's a form of social conservatism even in a liberal society," he said. "When it's a social question, France can seem split in two. Once it's resolved, it goes just fine."