When Maura Caldwell was nine months pregnant and working out at her Minneapolis gym, people would often ask to take her photo. Not because she was deadlifting 135 pounds, but because she was doing it with her toddler strapped to her back.

"I love working out and when Grandma wasn't able to come watch my son, I'd just wear him at the gym and add a little extra weight to my workouts," Caldwell said. "Now, having had a second baby, I find babywearing even more valuable and essential."

"Babywearing" is a growing practice among a new generation of parents who are ditching the stroller in favor of strapping their babies — and sometimes even toddlers — into carriers to tote around on their backs, chests or hips. Unlike baby backpacks once used for toting infants to and from home, parents now rely on slings and soft carriers to bring their children with them wherever they go: to the gym, grocery store, concerts, even work.

Though babywearing has been met with safety warnings from the medical field, proponents say it helps infants thrive physically, socially and emotionally.

"I think babywearing is a great way to foster a baby's secure attachment with their caregiver, said Byron Egeland, emeritus professor of psychology at the University of Minnesota's Institute of Child Development. "Especially because with more working moms these days, babies don't have as much contact with mom as they had in the past."

For many parents around the world, babywearing has long been a cultural norm. But in the United States, it's been driven by the rise of attachment parenting, which some studies say nurtures a closer bond between parent and baby and, ultimately, a healthier child.

It's become so popular in Minnesota that parenting groups have sprung up to teach parents how to wrap a wiggling baby safely with 6 yards of fabric or attach them to their backs in carriers with shoulder and waist straps.

"Caregivers wear in the heat, the snow, the rain, at marches, at religious services, at weddings, at funerals, and wherever makes sense," said Emily Niemi, a Brooklyn Park mom and outreach coordinator for Babywearing Twin Cities, an education, support group and carrier lending library with 4,800 members.

Meeting the mainstream

Chris Blaisdell has become something of a baby carrier connoisseur. After having her third child, she found local babywearing support groups, spent hours perusing online message boards and began a collection of carriers (six at current count), including some to tote her 35-pound toddler around.

While wearing toddlers and preschoolers can be seen as extreme, parents like Blaisdell say the kind of closeness that comes from carrying their kids is essential to creating a healthy and lasting bond. And sometimes, it's just the safest option.

"It started for convenience, but it continued for the closeness. He can snuggle in and just be with mom," the 40-year-old Hopkins woman said. "Sometimes I'll wear him if we're going to a busy event and I can't trust that he won't run off."

As babywearing goes more mainstream, the number of carrier options is growing, too. From a handful of baby-carrier vendors 20 years ago, hundreds now exist, offering a wide range of prices and styles. From pouch-like natural-woven slings to stretchy wraps that tie around the body, the baby carrier market grew 3.9 percent from 2016 to 2017 and is estimated to grow another 4 percent by 2022, according to TechNavio, a market research firm.

While Kylie Jenner was recently photographed with her 4-month-old buckled into a $625 Gucci baby carrier, one of the most popular baby gifts on Amazon is a $30 Infantino carrier. Retailers are even marketing special T-shirt style carriers for dads.

"It used to be that we were educating consumers about what baby carriers were, period," said Linnea Catalan, executive director of the Baby Carrier Industry Alliance. "Now I think most parents seem to be at least aware that it's an option and they are a common [baby shower] registry item."

Babywearing parents are also turning to social media to find in-person support groups, Facebook pages and YouTube tutorial videos. The topics they address seem almost endless: pole-dancing and yoga while babywearing, breast-feeding while babywearing, tandem babywearing, and babywearing dads.

Safety first

As babywearing has grown in popularity, its safety has been weighed against the benefits. While the practice is lauded for helping infants thrive, the federal government has unveiled new safety standards (see sidebar) for baby sling carriers after 17 deaths and 67 injuries were reported from January 2003 to September 2016.

"Parents should always check with their medical providers first, as some babies that spent time in the NICU might not have enough muscle strength for airway support in a carrier," said Hannah Kull, a nurse practitioner with Children's Minnesota.

Still, Kull and others tout the benefits of babywearing.

"We know that when a mother holds her baby close, her oxytocin levels increase, which helps with bonding," she said. "Carriers are a great way for dad to bond with baby, too."

Patrick Stephenson wears his 10-month-old daughter while having coffee with friends, visiting local breweries, seeing outdoor concerts, walking the neighborhood, traveling to New York, working and doing chores.

"She comes everywhere with us," the 35-year-old Minneapolis dad said. "We always joke that I'm the fun dad, while my wife is the cuddle mom, but I need cuddles, too. That closeness is unbeatable, with her pressed up tight against my chest drooling all over me."

Aimee Blanchette • 612-673-1715 Twitter: @aimeeblanchette