The migrants sent an SOS signal to Alarm Phone, a volunteer-run Mediterranean rescue hotline, saying the wooden boat they were in had run into difficulty after two days at sea.
"One pregnant woman is bleeding and maybe lost her child," the hotline said on Twitter, adding that those on board, including children, had run out of water.
Malta said it was monitoring the situation, before agreeing to rescue the migrants after several hours.
"The migrants were transferred to a patrol boat and are on their way to Malta," a coastguard spokeswoman said, asking not to be named.
The pregnant woman was "airlifted by helicopter," she said, declining to comment on her health.
Alarm Phone also reported what it was the second shipwreck off the coast of Tunisia in two days.