Editor's Note: (Kelly Wallace is CNN's digital correspondent and editor-at-large covering family, career and life. Read her other columns, and follow her reports at CNN Parents and on Twitter.)
(CNN) If you had to guess what are the most difficult years for a mother, what might you say?
Infancy? Sure, dealing with a newborn is beyond stressful, as you try to figure out how to care for an infant and adjust to a new role all on zero sleep. It would be no surprise if those years were the most taxing. But I -- and probably many of you reading this -- would guess adolescence, namely the high school years, which I might add I am already dreading.
But it turns out the most stressful time for moms is middle school, at least according to a new study by Arizona State University researchers published in the January issue of Developmental Psychology.
"I was a little taken aback to see that apparently preadolescence is the new adolescence or junior high school or middle school is the new high school," said Suniya Luthar, one of the study's co-authors and a professor of psychology at Arizona State University.
The study involved analyzing surveys from more than 2,200 well-educated moms across the country (more than 80% had a college or graduate degree), with children ranging in age from infant to adult. Researchers then compared how mothers who only have children in one age group (infant, preschool, elementary school, middle school, high school and adult) rated their feelings about their lives.
Across the board, mothers of only middle-school-age children reported the highest levels of stress, loneliness and emptiness, and also the lowest levels of life satisfaction and fulfillment. Mothers of infants and adults were found to be the most satisfied, Luthar said.
This probably shouldn't be a surprise. Think about what's happening to children in middle school: raging hormones, changing bodies and brains, exposure to peer pressure and risky behaviors like experimenting with drugs and alcohol, and a clash between a desire to be independent, but still feeling dependent on Mom and Dad.
"You see this person who is almost but not quite grown-up physically, saying at one moment, 'Leave me alone. I've got this figured out. Let me do it my way,' or 'Don't ask me questions,' and so on, and on the other hand, they (are) crushed in tears, and looking to you for comfort just like a child. They might cry like the children they used to be, but being able to actually comfort them is nowhere near as easy," said Luthar, who is also professor emerita at Columbia University's Teachers College.
What makes this so hard for parents is that the changes often happen so quickly, said Cynthia Tobias, co-author of the book "Middle School: The Inside Story: What Kids Tell Us, But Don't Tell You." which involved interviews with hundreds of middle school students across the country.
"For a lot of parents, it's just almost overnight. You hear a lot of times, they'll say, 'It's like I woke up with an alien this morning. Yesterday I had a child who loved to snuggle. Today I have a kid who can't even stand to be around me,' " said Tobias.
The biggest conflicts come when parents don't realize their children are starting to see themselves as young adults and don't respond accordingly, said Sue Acuña, who co-wrote "Middle School: The Inside Story" with Tobias, and who has been teaching middle school for more than 20 years.
"When the parents try to treat them as if they're still 8 or 9 years old, there's pushback ... and that catches the parents off guard and then sometimes they panic, 'Oh no. This is what I've always feared in adolescence,' and they come down harder instead of softer," said Acuña, who also writes a blog on middle school.
Michelle Icard has been working with middle school children and teachers for over 10 years and developed a special middle school curriculum targeting boys and one targeting girls that is used at schools around the country.
"I see these moms ... you can read it on their face," said Icard, who is also author of "Middle School Makeover: Improving the Way You and Your Child Experience the Middle School Years." "They're highly stressed. They're nervous. They don't know what to do."
Icard said parents would benefit by knowing the facts about middle school, how children are going through what she calls "the middle school construction project" as they start to develop a new body, new brain and new identity around age 11.
"If you know that, for example, your kid has to create an identity apart from you when they are in middle school so that they can form healthy relationships with people in the future, it makes it a little easier to bear so it's not for nothing that your kid is separating and relying on their peers. That's how they figure out their way in the world," said Icard, founder of the blog Michelle in the Middle.
At the same time our children are going through this "perfect storm" of changes, said Icard, many moms are kind of going through "a middle age construction project."
For moms who chose to stay at home during the elementary school years, this might be the time when they consider going back into the work force, which can be stressful. Mothers are also adjusting to getting older themselves and feeling a bit superfluous, no longer being the center of their child's lives. Some research also shows that marital satisfaction is lower during the teenage years versus the years after a child is born.
For all these reasons, Icard suggested moms make sure they have a passion, hobby or something that they enjoy for themselves when their children are in middle school. "You'll be modeling good self-care for your kid and when things get really tumultuous and they're illogical and they're unpredictable, you have something to dive into that makes you happy and that does a lot for stress reduction."
What parents might not realize is that their children may act like they don't want a relationship with them during the middle school years but they really do, said Tobias and Acuña, who heard over and over again from children who wanted their parents to be involved in their lives.
The quandary is that on the one hand, kids will say their mom is always asking them questions such as who are they texting, but on the other hand, they'll say their mom never wants to know what's going on in their lives and never listens, said Acuña.
"I say to them, 'Well, do you want your parents asking questions or not?' " she said. Their reply? "Well, they just have to know when it's a good time to ask a question."
I can hear mothers of middle school children screaming at this very moment: How are we supposed to know when it's a good time to ask a question?
Acuña, who has three sons, all now in their 20s, described how she would find one of her sons during the middle school years slumped in his bedroom with the door open. She'd walk by and ask if he was OK. Then she'd say, "Is this where I'm supposed to be concerned parent and talk to you or is there where I'm supposed to give you your space?"
Her son would usually say he was alright, but then as soon as she started to walk away, he'd say something like, "It's just that I don't understand why people act the way they do," she said. That was her cue to slink back into his room, sit on the floor and be prepared to listen.
Icard, who has an eighth-grader and a sophomore in high school, said mothers should learn how to listen and become more neutral in their responses by adopting what she called a "Botox brow."
"I say to parents. You don't actually have to get Botox. ... but you have to have that look like your brow doesn't wrinkle," she said.
"Studies show that kids cannot read facial expressions and their default is thinking you're angry when you're not," she said. "So adopt a 'Botox brow' and have a really neutral face when you're talking to your kid. You'll be surprised how much your kid opens up to you and starts coming to talk to you more."
Middle-schoolers often feel their parents don't take them seriously and sometimes we, as parents, don't, said Tobias, who along with Acuña put together free guides for parents, including "The No-No List" for talking to kids in middle school.
"We'll catch ourselves saying, 'Oh for heaven's sake, wait until you're old enough and you have to pay a mortgage and then you're going to think it's no big deal,' but to them, their whole world right now is middle school so they can't even think in terms of what we're talking to them about sometimes," said Tobias, who taught high school for eight years and has written 13 books about learning styles and strong-willed children. "So I think they just want a little chance to be heard. They want to be understood and listened to and they want to make sure that we do take them seriously."
Acuña, who teaches eighth grade, said parents should also realize other communication mistakes they often make with their middle-schoolers, such as interrupting them or finishing their stories. Think how you would feel if someone did that to you as an adult, she said. That is how a child will feel.
The most successful kids, she said, in her experience, are the kids who feel their parents have their back no matter what and that even if they mess up, their parents will be supportive.
She described her parent-teacher conferences, which are led by the student presenting his or her work to the parent. "The successful kids, they'll tell their parents, 'Yes, I messed up here. This is what I'm going to do to work on it' and their parents are very supportive," she said. "The anxious kids are the ones who when they say to their parents, 'Well, here's a test I didn't do well on,' the parents go off on them. ... The parents are upset and critical and (say), 'Well you are going to be grounded for that.' These are the kids who are afraid to take risks because they don't feel that their parents will support them."
Figuring out how to talk to your tween or teen and how involved to be could make even the most relaxed parent a tad crazy, but the bottom line from the middle school experts I talked with is that parents should do everything in their power to resist the urge to toss up their hands and give up.
"The parents have this tendency to just (say), 'Fine. You don't want to talk. Just don't talk,' and walk away," said Tobias, who has twin 24-year-old sons. "But the kids themselves, they told us over and over, 'We do want to keep a relationship with our parents. There's so much going on we just can't do it. We hope that they don't walk away.' "
Middle school is not a time to "tread water and wait out until they go through it," said Acuña. "It's not just a phase they're going through. There are some key things happening and it's a really important time to develop a relationship that will carry you through the teen years and into young adulthood."
Luthar, the researcher and psychology professor who has two kids of her own, ages 21 and 25, agreed and also urged mothers to reach out to other moms of middle-schoolers for support.
"If ever there were truth to the saying, 'It takes a village,' it's now," she said. "It's not it takes a village to raise a child. It takes a village to raise a preteen."
Why do you think middle school is the most stressful time for mothers? Share your thoughts with Kelly Wallace on Twitter @kellywallacetv or CNN Health on Twitter or Facebook.