At the time of their birth Sunday night, physicians said that the first 72 hours were the most critical for the sextuplets. The medical experts listed a number of life-threatening conditions faced by premature babies.
That assessment proved to be correct, because the fourth sextuplet, named Diego, died of lung and heart problems Wednesday afternoon. The child had been moved to Hospital San Juan de Dios immediately after the birth.
The mother, Silvia Villegas, remains in Hospital México where three of the sextuplets are in intensive care. She has been able to see her children there.
The six babies were around 2.2 pound each at birth at the end of the 27th week of pregnancy.