A Houston couple welcomed two sets of twins on Valentine's Day.
Tressa Montalvo, 36, gave birth to two sets of identical twin boys via Cesarean section at The Woman's Hospital of Texas. Two boys were in one placenta and the other two were in a second placenta.
Ace and Blaine were born at 8:51 a.m. and weighed 3 pounds 10 ounces and 3 pounds 15 ounces. Cash and Dylan were born at 8:52 a.m. and weighed 2 pounds 15 ounces and 3 pounds 6 ounces.
"We tried to stick to the A-B-C-D theme when naming them," said Tressa. "We didn't expect it, we were trying for just one and we were blessed with four."
When Tressa was 10 weeks pregnant, her doctor told her she was having twins. On a later visit, a third heartbeat was detected. A fourth baby was later discovered.
"No fertility drugs were used. We planned the pregnancy -- I guess we just succeeded a little too much!" Tressa said.
According to The Woman's Hospital of Texas, the odds of delivering two sets of naturally-occurring identical twins is somewhere in the range of 1-in-70 million.
Tressa and her husband, Manuel, also have a son.