If you are a woman experiencing depression, an anxiety disorder, or another mental health condition, you are not alone.

According to a recent survey by the Substance Abuse and Mental Health Services Administration, 29 million American women, or about 23 percent of the female population, have experienced a diagnosable mental health-related disorder in the last year alone. And those are just the known instances.

Experts say that millions of other cases may go unreported — and untreated.

Mental Health: Women’s Health Issues

Some mental health conditions occur more often in women and can play a significant role in the state of a woman's overall health.

While men experience higher rates of autism, early onset schizophrenia, antisocial personality disorder, and alcoholism, mental health conditions more common in women include:

Depression. Women are twice as likely as men (12 percent of women compared to 6 percent of men) to get depression.

Women are twice as likely as men (12 percent of women compared to 6 percent of men) to get depression. Anxiety and specific phobias. Although men and women are affected equally by such mental health conditions as obsessive-compulsive disorder and social phobias, women are twice as likely as men to have panic disorder, generalized anxiety, and specific phobias.

Although men and women are affected equally by such mental health conditions as obsessive-compulsive disorder and social phobias, women are twice as likely as men to have panic disorder, generalized anxiety, and specific phobias. Post-traumatic stress syndrome (PTSD). Women are twice as likely to develop PTSD following a traumatic event.

Women are twice as likely to develop PTSD following a traumatic event. Suicide attempts. Men die from suicide at four times the rate that women do, but women attempt suicide two or three times more often than men.

Men die from suicide at four times the rate that women do, but women attempt suicide two or three times more often than men. Eating disorders. Women account for at least 85 percent of all anorexia and bulimia cases and 65 percent of binge-eating disorder cases.

Mental Health: Women’s Symptoms Are Also Different

Even when men and women share a common mental health diagnosis, the symptoms, and subsequently the treatment, can be different.

For example, a man who is depressed is likely to report job-related problems, while a woman is more likely to report physical issues, like fatigue or appetite and sleep disturbances. Unlike their depressed male counterparts, women tend to develop problems with alcohol abuse within a few years of the onset of depression. Women are more likely to use religious and emotional outlets to offset the symptoms of depression compared to men, who often find relief through sports and other hobbies.

Women with schizophrenia more often experience depression and thought impairment, while men with schizophrenia are more likely to become apathetic and socially isolated. Women with schizophrenia typically respond faster to antipsychotic medication and need less personal care. Schizophrenic women also report more mood symptoms, which can complicate the diagnostic process and may require a prescription for mood stabilizers in addition to anti-psychotic medications.

Mental Health: Why the Gender Differences?

What goes on in the female brain and body to differentiate these responses to mental illness? The answers may lie in:

Biological influences. Female hormonal fluctuations are known to play a role in mood and depression. The hormone estrogen can have positive effects on the brain, protecting schizophrenic women from severe symptoms during certain phases of their menstrual cycles and maintaining the structure of neurons in the brain, which protects against some aspects of Alzheimer’s. On the less positive side, women tend to produce less of the mood stabilizer serotonin and synthesize it more slowly than men, which may account for the higher rates of depression. A woman’s genetic makeup is also believed to play a role in the development of such neurological disorders as Alzheimer’s.

Female hormonal fluctuations are known to play a role in mood and depression. The hormone estrogen can have positive effects on the brain, protecting schizophrenic women from severe symptoms during certain phases of their menstrual cycles and maintaining the structure of neurons in the brain, which protects against some aspects of Alzheimer’s. On the less positive side, women tend to produce less of the mood stabilizer serotonin and synthesize it more slowly than men, which may account for the higher rates of depression. A woman’s genetic makeup is also believed to play a role in the development of such neurological disorders as Alzheimer’s. Socio-cultural influences. Despite strides in gender equality, women still face challenges when it comes to socio-economic power, status, position, and dependence, which can contribute to depression and other disorders. Women are still the primary caregivers for children, and it is estimated that they also provide 80 percent of all caregiving for chronically ill elders, which adds stress to a woman’s life. Girls tend to become dissatisfied with their bodies at puberty, a reaction that is linked to depression. Girls are also sexually abused more often than boys, and one in five women will experience rape or attempted rape, which can lead to depression and panic disorder.

Despite strides in gender equality, women still face challenges when it comes to socio-economic power, status, position, and dependence, which can contribute to depression and other disorders. Women are still the primary caregivers for children, and it is estimated that they also provide 80 percent of all caregiving for chronically ill elders, which adds stress to a woman’s life. Behavioral influences. There is some thinking that women are more apt to report mental health disturbances than men and that doctors are more prone to diagnose a woman with depression and to treat the condition with mood-altering drugs. Women are more likely to report mental health concerns to a general practitioner, while men report tend to discuss them with a mental health specialist. However, women are sometimes afraid to report physical violence and abuse.

Mental Health: Ongoing Research

While distinctions between men and women weren't always clearly made in mental health research, in recent years government mandates have encouraged federal agencies such as the National Institutes of Health to respond to the need for mental health research specific to women. Private organizations are also responding to the need to research men’s and women’s health issues separately.

For example, researchers at the Women’s Health Research Center at Yale University in New Haven, Conn., are studying many issues related to women's mental health, including:

Differences in brain development that may provide insights into treating and preventing depression and bipolar disorder

Mood and memory processes in women that may make it harder for them to quit smoking

Effects of estrogen on memory, behavior, cognition, and emotion, and particularly how estrogen seems to increase rates of PTSD and depression

Genetics specific to women that may contribute to alcoholism

As more research comes to light and there is greater understanding of women’s mental health issues, experts are hopeful that targeted treatments will bring better results and more positive outcomes for women with mental health conditions.