Texas mother's sets of identical twins

A Houston, Texas mother has given birth to not just any quadruplets but two sets of identical twins -- which occurs in one in 70 million deliveries. The babies were born on Valentine's Day 2013 at The Women's Hospital of Texas in Houston.

AP Photo/Houston Chronicle/ Brett Coomer

"We tried to stick to the A-B-C-D theme when naming them," mom Tressa Montalvo explained in a press release. "We didn't expect it, we were trying for just one and we were blessed with four."

Baby Ace lies in an incubator. He was the first one born at 8:51 a.m. and weighed 3 lbs., 10 oz.

Thirty six-year-old mother Tressa Montalvo found out she was carrying the special bundles of joy 10 weeks into her pregnancy.

Ace Montalvo is shown in the NICU at The Women's Hospital of Texas on Monday, Feb. 18, 2013, in Houston.

Ace's identical twin brother, Blaine, rests under UV light. He was born at 8:51 a.m. like his older brother and weighed 3 lbs., 15 oz.

"When we got to Dr. Kirshon's office, he was quick to say right away, 'You have four,'" mother Tressa Montalvo said to CBS affiliate KHOU in Houston, Texas. "And, of course, I just couldn't believe it. If I wasn't already lying down on that table, I would have been on the floor."

Blaine Montalvo is shown in the NICU at The Women's Hospital of Texas on Feb. 18, 2013, in Houston.

Baby Cash was the first to be born of the second set of identical twins. He was born at 8:52 a.m. and weighed 2 lbs., 15 oz.

Cash Montalvo is shown in the NICU at The Women's Hospital of Texas on Feb. 18, 2013, in Houston.

Finally, Dylan -- the last of the four, was born at 8:52 a.m. as well. He weighed 3 lbs., 6 oz.

Dylan Montalvo is shown in the NICU at The Women's Hospital of Texas on Feb. 18, 2013, in Houston.

"We couldn't have been more surprised when Dr. Kirshon told us we were having four babies and that they were two sets of twins," father Manuel Montalvo, Jr. said in a press release. "We were trying for one little brother or sister for our two-and-a-half year old son, Memphis."

Manuel Montalvo holds his 2-year-old son, Memphis, as he looks in on Ace Montalvo, one of his four newborn sons at The Women's Hospital of Texas on Feb. 18, 2013, in Houston.

Two-year-old Memphis says hello to his new brothers with his father Manuel.

Tressa Montalvo places her hand on her newborn son, Blaine, at The Women's Hospital of Texas on Feb. 18, 2013, in Houston. Montalvo gave birth to two sets of identical twins on Valentine's Day, born at 31 weeks. The arrival of Ace and Blaine then Cash and Dylan a minute later was even more unusual because the Montalvos did not take fertility drugs or use in-vitro fertilization.

"No fertility drugs were used. We planned the pregnancy -- I guess we just succeeded a little too much!" Tressa said in a press release.

Mother Tressa spends time with one of her new infants.

Tressa said the pregnancy was a lot to handle at times.

"It was overwhelming. You sit there and you're crying and you're not even sure why you're crying. It's just everything," Tressa told KHOU. "Are you excited? Are you afraid? It's just everything. All the emotions come flowing in."

However, Tressa told KHOU that she was looking forward to having a big family.

"We do feel like we hit the jackpot yeah," Tressa said to KHOU. "The biggest blessing ever. Tremendous."

One of the quadruplets gets a bit of rest in an incubator.

"Our physicians, nurses and staff have been providing care exclusively to women and infants for more than 35 years," Women's Hospital of Texas in Houston CEO Linda Russell said in a press release. "This is what we do every day. We have the top specialists and an integrated continuum of care to make sure families like the Montalvos are getting excellent care. We want our families to feel confident that they are in the most capable hands."

With five boys, the family is sure to be quite hectic -- but there might be room for one more. "We want a girl," Manuel said in a press release.