A children's guardians could no longer be labelled “mother” and “father” on official French school documents, but “parent 1” and “parent 2”.
The change was part of an amendment to a new draft education bill, which supporters say seeks to put an end to discrimination against same-sex parents.
Passed by MPs on Tuesday, it could still be rejected by France's Senate, which houses a right majority, but will then go back to National Assembly for a final reading.
"This amendment aims to enshrine in legislation the family diversity of children in the administrative forms submitted to the school," said Valérie Petit, an MP from Macron's La Republique En Marche! (LREM) party, who drafted the text.
She argued that it took into account France's adoption of laws on same-sex couples marrying and having children.
However, its critics say that the change is "dehumanising".
"No child has a parent 1 or parent 2, that doesn't exist, it's in the realms of the absurd," Ludovine de la Rochere from La Manif Pour Tous, a collective that opposes same-sex marriage and same-sex parenting, told French radio RTL.
#parent1parent2: Here's what the Twittersphere had to say
Twitter users both for and against the change expressed their opinions on the social media platform, while some made light of the situation.
Twitter user Gary Roustan pointed out that on tax forms where couples declared together, individuals were already labelled "declarant 1", "declarant 2".
"Homophobes/sexists want us to believe that they aren't, by explaining that their problem with #Parent1Parent2 it is that it prioritizes parents. Oddly, there have never been any earlier claims against "declarant 1, declarant 2" for taxes..." he wrote.
A group called Les Stylos Rouges (red pens), which said it aims to give a platform to those working in the education system, made an alternative suggestion for how school forms might be laid out, using a list to show "legal guardians".
MEP Nicolas Bay, a member of France's right-wing National Rally party, wrote: "One father, one mother! Stop theis pseudo-'progressive' delirium! #Parent1Parent2."
A couple of Twitter users made light of the situation, joking that in France Star Wars character Darth Vador would now say "Luke I am your parent 1", rather than the famous line "Luke I am your father".