After Ann’s daughter was born, the infant cried a lot because of acid reflux. “When she wouldn’t stop, I got angry. I felt like a monster,” said Ann, who requested that she be identified only by her middle name because of privacy concerns.

At first, the new mother chalked up her irritability and guilty feelings to stress and sleep deprivation, but when the worrisome feelings lingered, Ann knew something was wrong.

When her daughter was 6 months old, Ann saw her physician, who diagnosed her with postpartum depression (PPD), the most common complication of childbirth, affecting 1 in 7 women, according to the American Psychological Association.

Symptoms of the illness can include frequent tearfulness, feelings of hopelessness, fatigue and, in rare instances, thoughts of self-harm.

Researchers from Northwestern University, in January, identified four risk factors that may help physicians and mental-health professionals predict the seriousness of postpartum depression. The factors are: education, the number of children a woman has, ability to function at work and at home, and depression severity at four to eight weeks postpartum. The study findings show that postpartum depression can vary in severity, which can affect the type of treatment a woman might need to recover.

“This information can help us predict the severity of maternal depression, which can benefit the well-being of a mother early on,” said Sheehan Fisher, lead author of the study and assistant professor of psychiatry and behavioral sciences at Northwestern University’s Feinberg School of Medicine.

The longitudinal study included 507 women diagnosed with postpartum depression. Each woman completed mental-health questionnaires and clinical interviews at four to eight weeks, three months, six months and 12 months postpartum.

According to the researchers, postpartum depression can fall into three categories: gradual remission, partial recovery or chronic severe. “Women who partially improve and those with chronic depression are at a higher risk of relapse,” Fisher said.

After her diagnosis, Ann expected to recover, but her depressive symptoms never entirely went away — even after taking an antidepressant. Nine months after seeing her physician, the feelings of irritability and worry grew stronger.

“I knew something wasn’t quite right because I started isolating from others,” Ann said. Still, the return of intense feelings caught her off guard, because her physician never mentioned that they could become severe again.

Before becoming pregnant, Ann had struggled with depression, a risk factor for postpartum depression. Her physician never asked about her mental-health history, Ann said. As a result, she was never screened for the disorder during pregnancy or immediately after giving birth, she said.

Early depression screenings may keep moms such as Ann from falling into the shadows. Fisher said that mental-health screenings can help identify at-risk women who might otherwise go untreated. “Mothers with severe depression are less likely to receive mental-health counseling, but early intervention and tailored treatment is an essential part of their recovery,” he said.

Symptoms of severe prenatal and postpartum depression can include feelings of hopelessness and anhedonia, a loss of interest in things, which can make it challenging for these women to make it to their prenatal checkups, according to Fisher.

“Moms who don’t receive regular prenatal care are less likely to be screened for mental-health concerns, which can make early intervention more difficult,” he said.

Although postpartum depression is common, each woman’s symptoms can vary, which means treating the illness doesn’t always fit into a “neat little package,” said Samantha Meltzer-Brody, a psychiatrist specializing in reproductive medicine at the University of North Carolina at Chapel Hill. She explained that personalized medicine could improve prenatal and postpartum mental-health care for mothers.

“Women diagnosed with breast cancer receive personalized treatment based on the type of cancer they have, which markedly improves treatment outcomes. We need a similar way to tailor perinatal mental-health care,” Meltzer-Brody said.

To do this, clinicians need to discern between the different types of perinatal mood concerns. “What is often labeled as ‘postpartum depression’ could be another mental illness, such as bipolar disorder. And some women experience primarily postpartum anxiety symptoms,” Meltzer-Brody explained.

Similar to postpartum depression, postpartum anxiety can cause feelings of irritability and ruminating thoughts to arise. However, mothers with anxiety may also experience physical discomfort such as nausea, dizziness and shortness of breath.

And sometimes, the two illnesses overlap. For instance, the latest research findings found that 64 percent of women with chronic postpartum depression also struggled with anxiety.

Kate Rope, 45, a mother of two children in Atlanta, suffered from postpartum anxiety. “I had a medically complicated pregnancy, which left me feeling anxious about my health and the health of my baby,” she said.

At that time, Rope was seeing a psychotherapist, but talking about her worries wasn’t enough to make them go away, she said. “By the time my baby was 9 months old, my brain was exhausted, and I wasn’t sleeping very much,” Rope added.

After months of endless worry and anxiety, she saw a reproductive psychiatrist who prescribed anti-anxiety medication. “Within two weeks, I felt like I exhaled for the first time in months,” Rope said.

Although Rope’s anxiety intensified after her baby was born, it had been present throughout her life.

“Anxiety has always been a ‘go to’ emotion for me, especially during stressful times. But there’s a spectrum of struggle, and it wasn’t crippling until after I had my first child,” she said.

Given her history, Rope was at a higher risk for a perinatal mood concern, but she was never screened for the disorder, she said.

Meltzer-Brody said learning about a woman’s mental-health history should be an essential component of prenatal care.

“We cannot tell women their ‘postpartum depression’ will be quickly resolved without taking into account their personal histories,” she said.

Shana Averbach, a psychotherapist specializing in perinatal mental health in San Francisco, said each case of postpartum depression varies. “I adjust my treatment plan to bolster the net of support, depending on each mom’s severity of symptoms,” she said.

Mothers with more severe PPD symptoms may need therapy more than once per week, group support and medication. “When necessary, I also refer women to intensive outpatient programs that provide a higher level of care,” Averbach added.

The Food and Drug Administration approved the first drug for postpartum depression, called brexanolone, last month.

“My hope with brexanolone is that it will be an important new treatment tool for appropriate women that suffer from severe PPD,” said Meltzer-Brody, who was the academic principal investigator for the drug’s clinical trials.

Since her symptoms worsened last year, Ann is starting to recover. “I’m mostly better, but I don’t feel 100 percent myself,” she said.

While medication has helped, Ann said one of the most valuable things is knowing she’s not alone. “Everyone expects motherhood to be joyful, but it’s validating to know other women find it difficult, too,” she said.

Recovering from postpartum depression is a journey, and sometimes the return of difficult feelings is part of the path, Averbach said. “However, healing is possible, especially with help,” she said.