African immigrants, whose boat sank off the Libyan coast, gather upon their rescue in Tripoli, capital of Libya, on April 13, 2017.
The migrants were 15 miles southwest of the Atlantic coastal town of Barbate, which lies between Cadiz and Gibraltar.
The boat sinking occurred off the Libyan capital of Tripoli's western suburb of Gargaresh on Thursday, said Libya's coastguard spokesman Ayoub Qassem.
The pregnant woman and 25 other migrants were aboard a vessel that was taking on water in the Atlantic Ocean when reached by the rescue boat Salvamar Gadir before daybreak Friday. The Libyan coast guard had rescued 23 migrants of various African nationalities, who were found clinging to a floating device, just under 10 kilometres (6 miles) off the coast of Tripoli.
"What happened is that the base of the boat got wrecked and the boat sank", Qassem said. Closer to the mainland, civil guard boats patrolling near Cartagena intercepted another two boats - one on Thursday with 11 men, a second craft on Friday with eight more men. More than 24,000 migrants arrived in Italy from Libya during the first three months of the year, up from 18,000 in the same period last year, according to the U.N. High Commissioner for Refugees.
Another survivor, Mohamed Amine from Mali, told the BBC: "We were at sea in the boat for three days... we were rescued after it capsized".