Erin and Jake Credo welcomed twin girls Lola and Allie on Sept. 22, six years after the arrival of sons Cooper and Grant
identical twins
Credit: NBC Local 33

A couple in Louisiana are seeing double again after welcoming their second set of identical twins.

Erin Credo gave birth to twin girls Lola and Allie on Sept. 22, six years after welcoming sons Cooper and Grant with husband Jake Credo.

Recalling her journey to become a mother of four, Erin said she was shocked and speechless when she learned that she was pregnant with twins again.

"When I had my ultrasound, I didn’t even know what to say. I texted a picture of the ultrasound to my husband, and he said, 'Is that the boys?' Nope. Round two," she told The Advocate. "He was, like, 'Oh, my God.' "

"Obviously, we were excited. We've done it before. Having twins, it’s all we know," Erin continued.

Dr. Cliff Moore, the physician who oversaw Erin's pregnancy, told TODAY Parents that "about 1 in 111,111 pregnancies results in a second set of identical twins."

"To put that in perspective, we deliver approximately 8,000 babies at Woman's Hospital each year, so we’d only see that about once every 15 years," Moore said.

Erin and Jake previously struggled to conceive their sons, so the pregnancy itself was a surprise for the Baton Rouge parents.

"We were kind of on the fence about having more because I didn’t want to go through that again," Erin said. "I never in my life thought I'd have four kids. I'm still in disbelief."

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However, the pregnancy did have some complications. According to The Advocate, Erin and her family all contracted the novel coronavirus (COVID-19) in August — though their cases were not very severe.

"The biggest concern they had was any respiratory issues I might be having," Erin recalled to the newspaper. "The shortness of breath was probably the most frustrating part of having COVID, because at what point does that shortness of breath cause concern? So, I just stayed in touch with my doctors constantly and kind of explained how I was feeling. Thankfully, we didn’t have any major issues that would have exacerbated the situation. We were really blessed."

Erin and Jake's daughters were born premature at 32 weeks and 3 days gestation. They remained in the neonatal intensive care unit until Tuesday, when they were released to the couple after gaining some weight.

"I'll always considered myself blessed with all these beautiful babies, but I also think God has a real funny sense of humor," Erin joked to NBC Local 33. "A lot of people say you're only given what you can handle, and I hope He has my back for the next few years!"