Updated

Twin boys delivered 24 days apart at Tufts Medical Center in Boston are doing well, the Boston Globe reported.

Lindalva DaSilva, 35, was only 24 weeks pregnant with her twins when she went into labor on February 27. Though doctors attempted to halt her contractions, they were unsuccessful.

As DaSilva went into labor, Dr. Sabrina Craigo, chief of Maternal-Fetal Medicine at Tufts, informed her of the possibility of delivering one twin, and keeping the other inside the womb, if conditions during the delivery were right.

"I thought it was absurd,” DaSilva told WCVB.com . "I said, 'I don't think -- I didn't know that was possible.'"

Delayed deliveries, which are extremely rare, can carry a risk of infection. They can only be performed on fraternal twins, who don’t share a placenta, and are only feasible if the mother’s contractions slow after the first baby is born, the Boston Globe reported.

Fortunately, after delivering son Alexandre, DaSilva’s labor slowed. She was treated with antibiotics and moved back to her hospital room to wait, while baby Alexandre fought for his life in the intensive care unit.

"[The doctor’s] like, leave him there. He's fine. His heart is beating well," father Ronaldo Antunes told WCVB.com. "Then we started praying."

Twenty-four days later, Alexandre’s twin brother Ronaldo was born. Craigo told the Boston Globe she’s delivered fewer than 10 delayed twin births in the last two decades – and never with as much time between deliveries accompanied by positive outcomes for both infants.

“One twin was born in winter, and one was born in spring,’’ DaSilva told the Boston Globe.

Both twins are still being treated in intensive care, but doctors say their prognosis is good – and they should be able to return home by their original due date, June 18.

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