Sarah Mariuz and Leah Rodgers delivered their babies on Thursday at 1:18am, in their respective time zones.
Rodgers' son, Reid Joseph, was born first, on Mountain time in Denver, Colorado. An hour later, Mariuz delivered her daughter, Samantha Lynne, on Pacific time in La Jolla, California.
The 35-year-old sisters hadn't planned to be pregnant at the same time, but ended up with due dates just four days apart.
Mariuz told People: "Twins have a special bond and it's hard to explain. We didn't plan on being pregnant at the same time, but our journeys aligned – even giving birth. There have just been certain things in our life where things just match up – it's odd. It's that magical twin connection, I suppose."
The sisters and their babies are doing well.
"It's a really cool thing to be able to share. The adventure will only continue as our babies share the same birthday like we did! We can't wait for them to grow up together," Rodgers added.
Today reports the families are trying to work out a time to visit each other.
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