So when Sarah Thistlethwaite, a math teacher from Ohio, was eagerly awaiting that first cry from her twins, but instead heard the delivery room doctor gasp, her heart plummeted. Sarah was on the other side of the screen during her Cesarean section and couldn't see why the doctor made such a startling noise.
The entire delivery room fell silent. They couldn't believe what they were seeing.
The obstetrician had lifted out the twins at the same time, instead of one at a time. That's because the doctor couldn't separate them...
Sarah admitted she was in shock when the doctor showed her the girls. She burst into tears.
Then she laughed. In fact, everyone in the room began crying and laughing out loud.
When Sarah was 19 weeks along in her pregnancy, she and her husband discovered that their identical twin girls were monoamniotic. That means the monoamniotic-monochorionic twins share the placenta, their amnions and chorions.
Sadly, these types of twins, also known as "mo-mo" twins, don't always survive and have an in-utero mortality rate of approximately 50 percent. It's the rarest form of twinning and carries the greatest risk.
When Sarah was just 33 weeks into her pregnancy, Sarah underwent the Cesarean section. She had been on bed rest for 57 days.
Knowing that the baby girls might need additional medical care after delivery, Sarah and her husband, along with family, friends and the entire delivery room, waited anxiously to learn the babies' health. So they were startled when they were born attached.
Fortunately, the attachment was only their hands -- as in, they were holding hands, clutching each other during the delivery. No one could believe what they were seeing, including Sarah and her husband.
"My heart just melted. Even my husband got tears in his eyes - I don't know that anybody in the room had a dry eye."
Sarah and her hubby named the twins Jenna and Jillian. They have grown up to be incredibly close, both physically and emotionally.
Sarah describes them as "two peas in a pod." The girls always take care of each other, she said.
"If one twin is crying, the other will try to find a way to comfort her, like going to find a pacifier or rubbing the other's back or offering a hug. Twins have this special bond and I can't wait to watch them grow up and be best friends."
Twins are double the fun and double the blessing. The video below shows how these sweet hand-holding newborns have grown up to be precious and precocious little girls.