If you're pregnant, chances are you've heard about postpartum depression. But did you know that many women also experience depression during pregnancy?

Here's what you need to know about pregnancy and depression.

Pregnancy can be a time of joy — and stress. Research suggests that about 7% of pregnant women experience depression during pregnancy. Rates might be higher in low and middle income countries.

Depression, a mood disorder that causes a persistent feeling of sadness and loss of interest, is the most common mood disorder in the general population. The condition occurs twice as often in women as in men, and the initial onset of depression peaks during a woman's reproductive years.

Some symptoms of depression, including changes in sleep, energy level, appetite and libido, are similar to symptoms of pregnancy. As a result, you or your health care provider might attribute these symptoms to your pregnancy, rather than depression.

Women might also be reluctant to talk to their health care providers about changes in moods during pregnancy, due to the stigma associated with depression. There's also a tendency to focus more on women's physical health during pregnancy, rather than mental health.

Some risk factors for depression during pregnancy include:

• Anxiety
• Life stress
• History of depression
• Poor social support
• Unintended pregnancy
• Intimate partner violence

The signs and symptoms of depression during pregnancy are the same as those that occur with depression in the general population. However, additional clues that might indicate depression during pregnancy include:

• Excessive anxiety about your baby
• Low self-esteem, such as feelings of inadequacy about parenthood
• The inability to experience pleasure from activities usually found enjoyable
• Poor response to reassurance
• Poor adherence to prenatal care
• Smoking, drinking alcohol or using illicit drugs
• Poor weight gain due to a decreased or inadequate diet
• Thoughts of suicide

Some research suggests that depressive episodes occur more frequently during the first and third trimesters.

If you have untreated depression, you might not seek optimal prenatal care, eat the healthy foods your baby needs or have the energy to care for yourself. You are also at increased risk of postpartum depression and having difficulty bonding with your baby.

Depending on the severity of your depression, treatment options might include psychotherapy or antidepressants in addition to psychotherapy.

The American College of Obstetricians and Gynecologists recommends that health care providers screen for depression and anxiety using a standardized tool at least once during pregnancy. During screening, your health care provider will likely ask questions from a standardized screening questionnaire, which consists of questions about mood and anxiety. Your answers are scored and your total score can be used to identify whether you have depression. Alternatively, your health care provider might ask you if, in the past month, you have been bothered by feeling down, depressed or hopeless or by having little interest in doing things.

There is limited evidence that screening to identify and treat depression during pregnancy improves outcomes. This might be due to variations in access to resources and appropriate treatment once depression has been diagnosed. However, screening for depression during pregnancy might provide some self-awareness of your risk of depression and anxiety.

If you think you might have depression during pregnancy, don't wait for a screening. Talk to your health care provider about how you're feeling and work with him or her to determine the next steps.