Chrissy Teigen – model, best-selling author and host of the Emmy-nominated show Lip Sync Battle – has revealed a part of her life that she’s kept private since the birth of her daughter, Luna, in 2016.

“I decided I’d talk about something no one really knows about me, mainly because I just learned about it myself,” Teigen says in the essay, which appeared in the March 2017 issue of Glamour.

After months of debilitating physical and emotional symptoms including lower back pain, nausea, exhaustion and intense mood swings, Teigen received an unexpected diagnosis: postpartum depression (PPD) and anxiety.

This diagnosis took her by surprise because her own experience didn’t fit the image of PPD that’s often presented in the news and pop culture. For example, she didn’t have any thoughts of harming her baby. “I also just didn’t think it could happen to me,” she says. "But postpartum does not discriminate. I couldn’t control it. And that’s part of the reason it took me so long to speak up."

What is Postpartum Depression

Postpartum depression is a mood disorder that affects one out of nine women, according to the Centers for Disease Control and Prevention (CDC). It happens after childbirth and typically involves feelings of extreme sadness and exhaustion. It can interfere with your ability to care for yourself and your family.  

There’s no one cause of PPD; it may be a result of:

  • Hormone and brain chemistry changes after childbirth
  • Sleep deprivation
  • Coping with caring for a newborn

You could be at a higher risk for PPD if you have a history of mental illness, you lack support or your baby has medical problems.

What are the Symptoms of PPD?

PPD can be different for everybody, explains Teigen. The condition shares many hallmark symptoms of depression, like a lack of interest in activities that once brought you joy and feeling constantly low. PPD is different from the “baby blues,” a term used to describe the short-term exhaustion and worry that almost every new mother feels.

Other symptoms of PPD include:

  • Crying more than usual
  • Frequent headaches or body aches
  • Eating too much or too little
  • Avoiding familiar people and places
  • Feeling a lack of attachment towards your baby
  • Worrying that you could hurt your baby
  • Feeling guilty or fearful about your role as a mother

For Teigen, “I was different than before. Getting out of bed to get to set on time was painful. My lower back throbbed; my shoulders – even my wrists – hurt. I didn’t have an appetite. I would go two days without a bite of food…I was [short] with people.”

Outside of work, she rarely left her home, unable to travel far from her couch. “During that time my bones hurt to the core. I had to go to the hospital; the back pain was so overwhelming,” she says.

PPD symptoms may begin right before or right after delivery, but typically occur one week to one month after you give birth.

Get the Help you Need for PPD

Teigen eventually opened up to her family doctor, who prescribed an antidepressant: “I looked up at my doctor, and my eyes welled up because I was so tired of being in pain.”

She also started talking – sharing her story with family, friends and coworkers, signing up with a talk therapist and publicly reaching out to other women facing PPD.

“Like anyone, with PPD or without, I have really good days and bad days. I will say, though, right now, all of the really bad days – the days that used to be all my days – are gone,” she says.

If you suspect you might have PPD, make an appointment with your OBGYN, therapist or family doctor. If left untreated, it can linger for months or years.

Speaking up is often the first step towards feeling like yourself again. “I [don’t] want to pretend like I know everything about postpartum depression, because it can be different for everybody. But one thing I do know is that – for me – just merely being open about it helps. This has become my open letter,” says Teigen.

This content originally appeared on Sharecare.com.