What is a rainbow baby? And why do some parents dislike the term?

After 24 hours of labor that was mentally, emotionally and physically exhausting, Teresa Mendoza met her daughter. Then, just one day after her due date, the baby died.

"Sylvia was my first pregnancy," the Washington-based nurse tells TODAY.com, adding that her pregnancy was routine.

"She had dark hair, long fingers and big feet; we like to think she would have been a dancer," Mendoza recalls. "Our families were able to be there, meet and hold her, celebrate her existence and grieve her death until we said goodbye."

This was not Mendoza's last pregnancy, though. When she last spoke with TODAY.com, she was pregnant with her fourth child, her "rainbow baby."

What is a rainbow baby?

A “rainbow baby” is a term used to describe children born after a miscarriage, stillbirth or neonatal death, like a rainbow at the end of a storm. The American Pregnancy Association says rainbow babies symbolize "hope, healing and something beautiful after a dark and turbulent time. This is much like the rainbow’s symbol of promise and light." There is even a Rainbow Baby Day: Aug. 22.

But pregnancy after loss isn’t all sunshine and rainbows. Many women experience a range of emotions, from fear to joy and everything in between.

What are misconceptions about a rainbow baby?

"One of the biggest misconceptions is that parents no longer grieve upon a subsequent healthy pregnancy," Dr. Rayna D. Markin, a clinical psychologist and associate professor of counseling at Villanova University, told TODAY Parents. "On the contrary, subsequent pregnancies can re-trigger a person's attachment to the lost baby and feelings of loss."

Markin, who specializes in pregnancy loss and infertility, said it's common to experience heightened anxiety like "a veteran home from war who sees danger around every corner."

Why do some parents reject the term rainbow baby?

Mendoza says the storm and rainbow reference might not be the best imagery to describe the loss of a pregnancy or baby. "Referring to anything with her as darkness or a storm felt like it focused strictly on her death rather than her very real life," she shares.

"Pregnancy and infant loss is already so very stigmatized and shrouded in families feeling isolated and pressured to ‘move on,'" she says. "My kids are siblings. One of them is dead and others are alive. I don’t feel the need to call their existence anything other than they are their sister’s brothers and she is their sister."

"Referring to anything with her as darkness or a storm felt like it focused strictly on her death rather than her very real life."

Meg Konig, a photographer and mom in Colorado, first heard the term shortly before she miscarried her daughter, Hope. When she delivered her son, Everett, after her loss, Konig says she wasn't "in love" with the idea of calling her newborn a rainbow baby, partly because she doesn't want to define Everett in relation to Hope.

"For me the term aligned with the idea that we wouldn't have 'tried for another baby' if we had had a successful birth with our previous pregnancy," Konig says. "It's been many years since our miscarriage, but when I think of losing Hope and then of having our son Everett, I think of it as two separate events."

Konig published her thoughts in an essay on the Colorado Springs Moms Collective and discovered she was not alone in her discomfort with the term.

Her baby Hope was not "a kind of tumultuous event that we had to overcome," Konig wrote. She wasn't the storm: "We want to remember her, herself, as the rainbow."

The mom of four echoed Mendoza's feeling that there's pressure to "get over" or "move on" from a loss. Storms pass, and then a rainbow appears. Loss doesn't clear up like a storm does.

"Loss cannot be compared or measured. My loss with Hope was deeply impacting, and I had to work through it for a very long time," she says. "The timeline for grief varies by each person, and there was no grand rule book or timeline for bereavement."

How does it feel to be pregnant after loss?

When Lida Mullarkey became pregnant after two devastating miscarriages, she kept her daughter’s sonograms hidden.

“They were there for me, but I didn’t want other people to see them,” Mullarkey told TODAY.com. “I had all these irrational thoughts. Like, if I post a pregnancy announcement on Facebook, I’ll jinx it. Or if I get excited, I’ll jinx it.’”

Worried that she could begin bleeding at any moment, Mullarkey struggled to bond with her baby during pregnancy.

"I was terrified of getting attached," she said.

How can you manage the stress of pregnancy after loss?

There are different ways to manage anxiety while pregnant with a rainbow baby. Dr. Jessica Zucker, a Los Angeles-based psychologist specializing in women's reproductive and maternal mental health, recommends support groups and mantra meditations.

"A mantra that can be particularly grounding during this period is, 'At this moment in time, I am pregnant. Everything is OK,'" Zucker told TODAY.com.

"Reminding yourself that this pregnancy is moving along healthily can be a powerful thing to appreciate in the midst of fear."

Erica McAfee, who hosts the “Sisters in Loss” podcast, lost her son Brandon Jr. at birth and her daughter, Brielle, when she was 18 weeks along in her pregnancy. McAfee also had a difficult time celebrating the life that was growing inside of her, at first.

“In the beginning I had so much anxiety and fear,” McAfee told TODAY.com. "I was bogged down with all these 'what ifs?'"

With the encouragement of a therapist, McAfee began to blog about her rainbow pregnancy experience and began connecting with moms who had experienced loss.

“It was so therapeutic for me,” she said. “I started celebrating every milestone. When I got to 24 weeks, I celebrated that because I didn’t get to 24 weeks in my previous pregnancy. I gave myself permission to appreciate my growing body. I didn’t want my baby to feel stress. I didn't want to transfer negative energy to him."

How can you help a friend who's pregnant after loss?

For those supporting a friend during a rainbow pregnancy, Zucker advises steering clear of platitudes such as, "At least you got pregnant again," "Everything happens for a reason," and "God has a plan."

"Instead, try, 'I'm here for you,' or 'What is it like to be pregnant after your loss?" the creator of the #IHadaMiscarriage campaign said. "Glossing over her loss, even if you think that's what she wants, doesn't make the current pregnancy less riddled in fear. Acknowledging her previous pregnancy might feel validating to her and illuminates that you are a friend who sticks around through the hard times as well as the celebratory ones. Be a friend who can hold both."

This story first appeared on TODAY.com. More from TODAY:

• Hoda Kotb opens up about what she plans to do after leaving TODAY and ‘instrumental’ guidance from friends
• Vanessa Rissetto's chest was always itchy. It was the first sign of breast cancer
• ‘Naked and Afraid’ contestant Sarah Danser dies at 34