Depression among young women aged up to 32 years
This section of the current review details the literature on the prevalence and correlates of depression among a population of young women in Australia , identified as being between 12 and 32 years of age. The average age of the women in this section was calculated to be 20 years of age.
Previous research has found a higher prevalence of depression among young women, compared to those in middle- or older age [58, 67]. In this review, estimates of depression among women aged 12 years and over range from 3.18% based on the Goldberg Depression Scale  to 30% using the CESD-10 . Moreover, as young women reach the later stages of puberty their risk of experiencing depressive symptoms increases . Young high school aged women experience a higher risk of depression than young men, with prevalence rates of 22% [72, 73], whilst women in their twenties are also more likely to experience depressive symptoms than men in their twenties [10, 42]. Young Asian Australian  and Indigenous Australian  women are particularly vulnerable to depression (53.8%) , having higher rates of prevalence than the general population, and these findings are discussed further in the specific topic sections in this review.
Two representative studies examined a range of correlates of depression. Among women aged 15 to 24 years, parental problems, sexual abuse, sexual identity conflict, financial difficulty, relationship break-downs, bullying, scholastic failure, and introversion were significantly associated with depression . For those women aged 22 to 27 years, higher levels of depressive symptomatology were associated with lower socio-economic level, unemployment, low educational level, being single, having high health services use, illicit drug and alcohol use, and smoking .
For young women in this age group, particular life events for example unemployment , relationship issues, separation and divorce, abortion or miscarriage, and the onset of sole motherhood, have been associated with depression [20, 54, 55]. Bottomley et al's.  study found that 30% of pregnant adolescents aged between 13 and 20 years were at risk of depression during pregnancy. Moreover, for young women in this age group, past experience of abuse is related to both depression and suicidality .
For young women, issues surrounding weight and diet are of particular concern. Poor body image and perceptions of being overweight during adolescence are a significant risk factor for depression in young women [29, 77], as is actually being overweight or obese , or conversely, being underweight [29, 77]. Frequent dieting , and restrictive dietary practices, such as vegetarian diets  have also been found to be associated with depression. 21% of young women on vegetarian diets experience depression; compared with 15% of women non-vegetarians .
The absence of physical activity is also associated with the presence of depression , however, whilst physical activity has been found to be protective of depression [59, 68], this effect may only apply to those women who are already at a healthy weight or alternatively, overweight (as opposed to obese) . While much research into weight and diet issues already exists, detailed investigation into the factors that underlie body image and weight problems would advance the development of highly targeted, positive, and responsive intervention strategies. Young women are at particular risk of weight issues and poor body image, and by association, increased risk of depression, and therefore targeted intervention programs may help to prevent depression at a young age, and the subsequent development of depression at later ages or stages of the life course, such as following the birth of their first child, or as they transition into middle age.
Overall, the literature offered reasonable coverage of the prevalence and correlates of depression in this age group. However, some areas that have been linked with depression warrant further investigation, including skin problems , young pregnancy , and pregnancy losses . Few studies have examined women’s transitions through life events , and therefore more longitudinal studies of this nature are warranted to determine those times when women are most vulnerable to depression. Additionally, an exploratory study with women in these age groups may help to identify those factors that the young women themselves implicate in the development of depression.
Depression in the pregnancy-related period
Depression during the pregnancy-related stage is a serious illness that impacts adversely on women’s quality of life , on social and role functioning, and on the mother’s ability to care for and experience a positive maternal relationship with her child . Following the birth of a child, around 70% of women will experience a short period of depressed mood commonly known as the ‘baby blues’. This depressed mood can last up to ten days, but is not considered to be postnatal depression or depression . Postnatal depression occurs within four to six weeks following the birth of a child and includes all of the symptoms of major depression, and potentially, disinterest in or fearfulness of the baby . Prevalence rates for postnatal depression among Australian women overall are 7.5% at six to eight weeks postpartum, however, point prevalence rates vary between states (from 10.2% in Queensland and South Australia to 5.6% in Western Australia) . Among certain groups of women, the prevalence of pregnancy-related depression is higher than that found for the general population. For example, women from Indigenous and culturally and linguistically diverse backgrounds [83–85], and sole mothers experience significantly higher rates of postnatal depression (18%), compared to 8% of mothers with partners .
From a life course perspective, the transition into motherhood increases the likelihood of women experiencing depression . Women who have previously experienced mental health problems  and those with a family history of mental health problems [86, 87] are most likely to experience pregnancy-related depression, which in turn increases the risk of developing depression at later life stages .
Some research also suggests that lower socio-economic status, and for example, accessing public hospital as opposed to private hospital services  is associated with depression. However, living in an affluent area has also been found to be associated with depression , and so the relationship between depression and socio-economic status, health care affordability and hospital choice warrants further investigation. More research is also indicated to determine the role of demographic profiling in identifying those women most susceptible to postnatal depression.
Clear evidence of a link between infant temperament and postnatal depression has also been found. Hiscock and Wake’s  study found that 46% of mothers considered their infant’s sleep as problematic, with behaviours ranging from sleeping in the parent’s bed, having to be nursed to sleep, frequent night time waking, taking short naps, and needing an adult to settle the child . Research has shown that having an ‘unsettled’ baby or one who did not sleep ‘well’ [89–91] increases the risk of postnatal depression, however, being able to maintain good quality sleep can ameliorate these effects [89–91]. It is considered that poor infant sleeping and self-settling habits are a learned behaviour, and amenable to behavioural change. Therefore, promoting effective infant settling techniques, encouraging good sleeping habits from birth and preventing maternal sleep deprivation may play an important role in helping to reduce postnatal depression.
Numerous research studies have explored the relationship between maternal psychology and postnatal depression. These studies have found that being nervy, angry, shy or introverted, and lacking in assertiveness or confidence, are aspects of maternal psychology that are correlated with postnatal depression [87, 89–91]. However, as infant and maternal temperaments are interactive, it is very difficult to establish causal pathways of postnatal depression. As already discussed, having an infant who is perceived as problematic or a poor sleeper can adversely impact on the relationship between mother and child, and increase the risk of postnatal depression. Moreover, relationship interactions between the mother and her partner must also be considered, as difficult marital relationships, partners who are unsupportive, controlling or critical, and domestic violence are also linked to postnatal depression [87, 90]. Lack of social support has also been found to be associated with postnatal depression .
Scope exists for more research in the area of postnatal depression to more fully determine the complex pathways and risk factors for postnatal depression, and the development of responsive and effective early intervention and support programs. This review found very little research focused particularly on depression during antenatal stages of motherhood. It is recommended that this be an area of future research.
Depression among women aged 32–64 years
Middle-age has been defined as being between 45 and 64 years of age . Whilst the literature included in the current review provided some information specific to middle-aged women and depression, age categories varied across studies, with the average age of middle-aged women being 37 years. It is noteworthy that of the three age groups reviewed, middle-age received the least attention from the literature.
In this age group, the prevalence of depression varied from 9.2%  to 24% , most probably attributable to variations in age groupings and other sample differences between studies. Despite methodological differences, the current review found that middle-aged women appear less prone to depression than younger women, but more prone to depressive symptoms than older women . Women aged 45 to 49 years were the most likely of all age groups to be admitted to hospital for a depressive disorder . Moreover, research has found that more females aged 60 years and over attempted and completed suicide compared to younger women . Suicide is 4.4 times higher in females when compared to the general population at older ages and 6.6 times higher among older women who have been in prior contact with mental health services . As depression is a very robust predictor of suicide in older age groups , more research into the severity of depressive symptoms at different ages is warranted.
Depression in middle-age shares similar correlations to those occurring among younger women, for example sole motherhood [54, 55], lower socio-economic status , a history of childhood abuse , or history of intimate partner abuse and domestic violence [54, 55]. Although some studies suggest that by mid-age many women may no longer be experiencing domestic violence, the psychological impacts of domestic violence or abuse can be long lasting [54, 55]. In one study, 39% of women who had experienced any type of abuse felt that the abuse continued to have a negative impact on their lives [54, 55].
A significant life stage event that occurs in middle-age is menopause. The current review found that those women who have experienced surgical menopause are at increased risk of depression, compared to those women who experience natural menopause . Additionally, those women who experience a longer menopause transition have higher depressed mood than those women who are postmenopausal . Moreover, the use of hormone therapies made no difference in level of depressive symptoms .
Other contributing factors and life stage events correlated with depression in middle-age are having prior pre-menstruation problems, negative attitudes toward ageing and menopause , life transitions out of relationships (separation, divorce), children leaving home, and the existence or onset of health problems.
The impact of physical activity on depression was also examined in the current review. Brown et al.’s  study of physical activity and depressive symptoms in middle-aged women concluded that physical activity is an important mediator of depression, with a representative sample showing a clear dose–response relationship between physical activity and psychological health . Noticeably in the current review, there were fewer investigations concerned with weight and exercise for women in the middle-age group than there were for younger women. However, this may be an important avenue of enquiry that could provide significant insights into reducing and preventing depression in middle-age.
In the current review, the lack of literature focusing on depression among middle-age women highlights the need for further research and investigation, and the development of responsive intervention and treatment programs for women in the 45 and over age group, particularly given the greater incidence of hospitalisations for depression, and relatively high risk of suicide compared to women of other ages.
Depression among women aged 64–93 years
The average age of women included in this section was 70 years. The current review found that older women are least likely to experience depression; however, depression among older women can impact substantially due to limited social and family networks and less robust coping mechanisms . Moreover, older women with depression may be less inclined to seek help due to generational stoicism, lack of understanding about depression, and fears about stigma or shame attributed to mental illness . It is also important to note that feelings of shame or stigma may preclude older women from disclosing depressive symptoms in a research context, and therefore any research findings may be skewed. Prevalence estimates of depression among older women in this review vary considerably due to differing sampling compositions, from as low as 1.77% , to 34.7%  of the representative samples. It is important to note that prevalence rates may vary depending on the setting (i.e. aged care facility, independent living and so on) and also the age of the older person. It is worth noting as part of this discussion that more recent literature suggests that while there is generally a lower prevalence of depression in older age there is an increase in psychological distress in the older stages of life, after 80 years of age . This discussion point requires further investigation and highlights the importance of measuring and understanding depression for women in this older age group.
Among women aged over 60 years, those most at risk of being hospitalised for depression were aged 70–79 years. Moreover, women in this age group are more likely to be hospitalised for depression than women aged in their early twenties . These findings highlight the importance of further research examining severity of depression at different ages of the life course, as mentioned in the previous results section.
Among older women, it is important to note that those residing in Australia but born overseas experience higher prevalence rates of depression than their Australian-born counterparts , and this is discussed further in the specific topic section. In common with other age groups, for women aged 64–93 years, smoking and lower levels of physical activity were associated with depression [67, 68, 95]. Physical and chronic ill health  and anxiety  were found to be comorbid with depression among older women, and these findings reflect research among younger women. However, older women present additional correlates of depression that may be considered characteristic of this age group, namely, falls and injuries , pain , functional decline and loss of preferred activities , increased dependence on others , poor dental health and concerns over appearance of teeth, gums or mouth, and denture problems . Quine and Morrell’s  study found that 34.4% of older women reporting problems with oral health or dentures had felt depressed in the previous four weeks. Given that poor oral health or ill-fitting dentures are able to be remedied through increased funding and access to oral health services, this is one area of social health policy that could have a significant impact on improving quality of life and reducing depression among older Australian women.
In the current review, being in receipt of a government pension was also associated with greater prevalence of depression among older women [58, 95], suggesting a link between lower economic status and depression. Older women’s reliance on government benefits may be attributed to widowhood, lack of opportunity to accrue superannuation or savings across the life course, disrupted work histories due to family, marital or caring responsibilities, and lower wages generally . Targeted social policies may help to alleviate financial insecurity among older women in Australia, and in turn reduce the burden of depressive illness in this age group. Further research is warranted therefore, to inform more responsive policy formation and development in this area.
The current review identified substantial gaps in research for this age group. In addition to those areas already discussed, and compared to research undertaken among young and middle-aged women, there is insufficient research on the experiences of abuse and depression among older Australian women. It has been suggested elsewhere in this paper that older women may choose not to disclose depressive illness or symptomatology due to stigma or shame, and therefore prevalence rates and research in this area may be incomplete. Despite the appearance of some lower prevalence rates of depression among older women, high rates of hospital admissions for depression among women aged 70–79 years, and the high rates of depression found in some clinical  and aged care settings  warrants further investigation. Further, the current review indicates more research is needed to fully understand the progress of depressive symptomatology over time and the life course.
Depression in specific populations
Depression among Indigenous Australian women
In 2009, Indigenous Australians accounted for 2.5% of the overall Australian population, of which an estimated 6% identified as Torres Strait Islander populations . In the current review, few studies of depression among Indigenous peoples were identified. Only four studies were found to meet the inclusion criteria for this review [24, 50, 84, 102]; and these studies utilised small sample sizes, ranging in size from 51  to 106  Aboriginal and Torres Strait Islander women.
Whilst the prevalence of depression among Indigenous peoples is undetermined, it is known that Indigenous Australians have 1.9 times higher hospitalisation rates for care involving mental and behavioural disorders than non-Indigenous Australians [1, 103]. Anxiety and depression are the foremost health problems reported by Indigenous women in Australia . Several small studies have reported very high rates of depression for Indigenous women, for example, Deemal . Also, studies indicate that Indigenous women appear to experience depression at higher rates than non-Indigenous women, for example, Butler et al.’s  study found that 29% of female Indigenous prisoners were experiencing depression (compared to 18% of non-Indigenous female prisoners). A number of correlates were found to be related to depression among Indigenous women, such as unemployment, smoking or having a partner who smoked cigarettes, physical abuse, low coping skills, anxiety, caring for other people’s children , and cannabis use ; however, the small sample sizes precluded statistical analyses, and the results are not generalisable.
It is important to note that identifying the presence of depression among Indigenous peoples is complicated by the use of translated instruments. For example, Campbell et al.  used the Townsville Aboriginal Islander Health Service (TAIHS) and Mount Isa (MTI) translated versions of the Edinburgh Postnatal Depression Scale (EPDS), which in comparison to the standard version, identified higher rates of postnatal depression among a sample of 210 Indigenous women who had given birth . While indicating greater sensitivity, this difference was not significant. Moreover, the researchers noted that the study was limited by the low number of women participants.
In terms of future research, the current review has highlighted the lack of knowledge about the prevalence and correlates of depression among Indigenous Australian women. Importantly, any future research must address the need for culturally appropriate measures and identification of depression and postnatal depression among Indigenous people, whilst displaying a high commitment towards cultural sensitivity and awareness.
Depression among culturally and linguistically diverse women
Thirteen studies that met the inclusion criteria for examining depression among women from culturally and linguistically diverse backgrounds were identified. The research included was limited, and many of the findings have been previously referred to, however the main findings will be reiterated here.
Overall, the studies in the current review indicated that having a background other than Australian and living in Australia was associated with depression among Asian Australian high/secondary school students , Filipina women , Vietnamese and Turkish new mothers , oncology outpatients , and older people seeking help at a memory clinic . Additionally, absence of social support, lower English proficiency, and being under 25 years of age was significantly associated with depression among new mothers [83, 85]. In the current review, the limited number of articles meeting the inclusion criteria and the small sample study sizes in general preclude the drawing of conclusions regarding prevalence or correlations of depression. There is a clear need therefore for further research in this area. Moreover, in common with Indigenous populations, it is important to emphasise that any research with people from culturally and linguistically diverse backgrounds must be conducted in a culturally appropriate and sensitive manner.
Rurality and depression among Australian women
Much contention exists over the role of rurality in mental health outcomes, with different studies presenting conflicting prevalence rates and correlations. For example, it is often assumed urban living presents a risk factor for the incidence of depression, whilst rural areas are thought to provide more socially stable, cohesive, and supportive environments. Conversely, other studies have identified higher prevalence rates of depression in rural environments [49, 92]. One study suggests rurality presents a risk factor due to typical predictors of depression such as isolation and poverty being exacerbated by rural environments . Whilst urban and rural environments can play an influential role in the prevalence rates of depression for women, the literature in the current review suggests that other factors such as poverty, unemployment, being female, lower socio-economic class, substance misuse, a history of childhood sexual abuse, poor social networks or low perceived social support, an adverse life event in the prior 12 months, size of primary support group, and marital status have a more profound influence on the prevalence of depression for women living in both rural and urban communities [24, 59, 88].
One difficulty identified in the review literature surrounding geography and assessing prevalence and correlates of depression among Australian women is that of measurement. The ability to measure and define what is rural, remote, urban or metropolitan areas is a complex task that may or may not take into account proximity to the nearest metropolitan area, access to health services, and population density. Some research studies in the current review clearly delineated and defined their geographic terms (for example, GISCA. (2012). About ARIA+ (Accessibility/Remoteness Index of Australia). Retrieved 20/09, 2012, from http://www.adelaide.edu.au/apmrc/research/projects/category/aria.html. However, in other studies geographical locations were not defined, and this is likely to contribute to discrepancies between the reported results and conclusions. More intensive research is needed to alleviate the lack of research in this area, and to more closely determine to what extent rurality influences the prevalence and correlates of depression among Australian women. Moreover, particular attention should be placed on developing common understandings and definitions of geographical measurement to resolve the differences in geographical measurement between studies, and increase the accuracy and generalisability of research findings.