They decriminalized abortion in Iparralde. In the 1970s, the feminist movement gained great strength in the French state on this issue. The law was introduced by Health Minister Simone Veil, and that's why it's called Veil Law.
At that time, between 250 and 300 women die each year from clandestine abortions. This made it easier for women from the South who wanted to abort to travel to the Northern Basque Country.
Mona Chollet, “Women Enter Politics” (Atlas of Critical and Comparative History of Le Monde Diplomatique)