After Lyndsey Altice's daughter, Ada, was born, the Wisconsin mom and her husband thought their childbirth experience was over.
But Altice, who delivered in a birthing tub, felt a strong contraction after her daughter's birth, followed by what she describes as "a second ring of fire."
"The doctor midwife said, 'Oh that's just the placenta coming,'" Altice recalled. "Then a nurse midwife said, 'Oh that's the water sack, I've never seen that before.' All the while I couldn't get any words out."
Although Altice's prenatal visits never had indicated she was carrying twins, she quickly realized that there was another baby on the way.
"The only words I could muster out were, 'Oh f---,' which really describes every feeling I was having," Altice said. "From the pain, to realizing there was another baby coming, to not being able to verbalize any of it to the doctor or my husband."
Seventeen minutes after baby Ada arrived, Altice's second daughter, Billie, was born. The twins joined an older brother, Django, who, like his parents, had been expecting to meet only one baby sibling.
"I had a midwife who checked position and measured fundal height every appointment, and I always measured correctly for a singleton pregnancy," Altice said. "We wanted to be surprised on gender. I was hoping for a girl and my husband's family is all boys so I was really crossing my fingers."
Altice got her girl, times two, and said once she realized her situation was real and not a "crazy pregnancy dream," she was overjoyed.
The twin girls were born in July 2019. Photos of the surprised look on the mom of three's face went viral after Altice shared her story on social media.
"It was just beautiful ... I will never forget the indescribable feelings behind those pictures," Altice said. "I was beyond happy. We were both so happy, and I think everything happens for a reason."
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Altice said she's still not sure how twins were not detected throughout the 38 weeks she was pregnant.
"I had two late ultrasounds," Altice explained, "one done by an OB-GYN and the other by a sonographer. The second one was longer and of all four quadrants. I think twin number two was basically in my back."
"I would feel my belly all the time and my midwife felt at every appointment," Altice continued. "You couldn't feel a second baby."
So how common is it for a twin to go undetected during a pregnancy?
Dr. Christine Greves, a board certified OB-GYN at Orlando Health Winnie Palmer Hospital for Women and Babies, says being unaware of a twin pregnancy is very rare when regular prenatal care is involved.
"An ultrasound performed later in pregnancy is unlikely to miss finding the second fetus or 'hidden twin,'" Greves said. "It could be more common when the babies share the same amniotic sac because the babies may be forced so closely together that shadowing could affect things on a quick scan, but cases like this one are very unlikely."
Today, Altice's twin girls are 1 year old.
"It's been so much fun watching them grow together, and my son is such a good big brother," she said. "It's so beautiful. It has definitely been challenging at times, but everything you go through as a parent is worth it in the end."