Postpartum depression received burgeoning attention in the past decades. In contrast, studies on antenatal psychological morbidity are only beginning to flourish. This might partially be due to the misconception that women were hormonally protected from psychological disturbances during pregnancy.1 Identification of patients with antenatal anxiety and depression is further made difficult by the similarity between somatic symptoms of anxiety and depressive disorders and somatic complaints commonly found in the normal course of pregnancy, such as fatigue and appetite change.2 However, recent studies revealed that rates of anxiety and depressive symptoms were actually higher during pregnancy than in the postpartum period,3,4 highlighting the significance of antenatal mental health problems.
It has been reported that 7–20% of pregnant women suffer from antenatal depression.4,5–7 Data on the prevalence of antenatal anxiety is more limited, although a study of second-trimester pregnant women found that 6.6% had antenatal anxiety disorders.5 The same study identified 14.1% of pregnant women having one or more psychiatric disorders but reported that only 5.5% received some form of treatment, showing that antenatal psychiatric problems are largely underdiagnosed and undertreated. This is a serious issue because mental health problems during pregnancy are known to exert adverse influences on both women and their offspring.5,8–10 Antenatal anxiety and depression are also powerful predictors of postpartum depression,3,11 although it is not clear at which point during pregnancy these psychological states are most predictive of postpartum depression. Indeed, antenatal psychological states appeared to be dynamic and changing in nature, with most studies demonstrating a generally increasing trend of depressive symptoms during pregnancy followed by a decline after childbirth.4,12 Unfortunately, good data on prevalence and course of other mental health problems during pregnancy are inadequate, particularly anxiety problems.
Finally, although information on risk factors for antenatal anxiety and depression is available in the literature,13,14 most studies focused only on one stage of pregnancy. A longitudinal analysis of risk factors across different stages of pregnancy is of value for examining how the effect of various risk factors changes across pregnancy. This has implications for developing effective prevention and early intervention strategies.
Our study aimed at estimating the prevalence and course of antenatal anxiety and depression across different stages of pregnancy and identifying demographic and psychological risk factors for antenatal anxiety and depression at each stage. We further examined whether antenatal anxiety and depression were associated with increased risk of postpartum depression.
MATERIALS AND METHODS
The study was approved by the institutional review boards of both the University of Hong Kong and the Kwong Wah Hospital. Written informed consent was sought from all participants. Based on power calculations,15 for a power of 80% for detecting a medium effect size of 0.5015 at a 5% level of significance and an attrition rate of 15%, a total of 345 pregnant women were needed. Four hundred twenty-three consecutive Chinese pregnant women at first presentation in the antenatal clinic of a regional hospital in Hong Kong were approached for participation in the study. The regional hospital serves a population of half a million persons of diverse socioeconomic background. Eligible women included all pregnant women of Chinese ethnicity above 18 years of age. Women having significant medical diseases, considering termination of pregnancy, or having conceived through in vitro fertilization were excluded.
A prospective longitudinal design was used. Participating women were assessed a total of four times. They were first assessed in the first trimester and were reassessed at the second and third trimesters and at 6 weeks postpartum. The first three assessment questionnaires were completed in the clinic, whereas the 6-week postpartum questionnaire was mailed to the participants, who were asked to send them back in a self-addressed and stamped envelope.
A number of questionnaires were administered at each assessment time point to assess antenatal anxiety, antenatal depression, postpartum depression, and risk factors. The Hospital Anxiety and Depression Scale16 was used to assess antenatal anxiety and depression. It is a 14-item self-report instrument with two subscales providing separate measures of anxiety and depression. Higher scores indicate higher levels of anxiety and depression. The validated Chinese version17 was used. The suggested cutoff of 7/8 was used for each subscale to identify probable cases of clinically significant anxiety or depression.16 The Hospital Anxiety and Depression Scale was chosen because it was specifically developed to measure anxiety and depression among medical patients by focusing on affective symptoms and excluding somatic symptoms such as dizziness, insomnia, and fatigue that are also related to physical disorders. As such, it is suitable for use among pregnant women and is superior to other instruments that may inflate the rates of anxiety and depression because many somatic symptoms are common experiences during pregnancy rather than a reflection of psychological disturbances. The Hospital Anxiety and Depression Scale has been validated among pregnant women with a sensitivity and specificity of 93% and 90%, respectively, for the anxiety subscale and 90% and 91%, respectively, for the depression subscale.18 The sensitivity and specificity of the Edinburgh Postnatal Depression Scale in identifying antenatal depression was only 64% and 90%, respectively.19
Postpartum depression was assessed with the Edinburgh Postnatal Depression Scale, a commonly used 10-item measure of depression in the postpartum period.20 The Chinese version has been validated among pregnant women in Hong Kong, with good psychometric properties.21 The recommended cutoff of 12/13 was used for screening probable cases of postpartum depression.20 This cutoff yields a sensitivity of 88% and a specificity of 93%.19
Risk factors examined included demographic and psychosocial risk factors. Information on age, marital status, parity, family income, past and current smoking behavior, and past and current alcohol use were sought.
Attitudes toward pregnancy was measured by two items: whether the pregnancy was planned (yes/no) and whether the pregnancy was wanted (yes/no). The Rosenberg Self Esteem Scale22 was used as a measure of global self-esteem. Perceived social support was measured by a 9-item self-constructed scale. It measures perceived support from significant others including husband, parents, parents-in-law, siblings, children, other relatives, friends, bosses, and colleagues on a 5-point Likert scale, from 1 (very unsatisfactory) to 5 (very satisfactory). The mean score was used as an index of perceived social support. Finally, respondents were asked to rate the quality of their marital relationships on a 5-point Likert scale, from 1 (very poor) to 5 (very good).
Information on demographic risk factors was obtained only in the first assessment (first trimester), whereas the Edinburgh Postnatal Depression Scale was included only in the last assessment (6 weeks postpartum). All the other instruments were administered in all assessments.
Statistical analysis was performed with SPSS 13.0 (SPSS Inc, Chicago, IL) and R 2.3.1 (The R Development Core Team, Auckland). Descriptive statistics were used to summarize the demographic characteristics of the sample. Attrition analyses comparing those who participated in all time points of the study and those who dropped out of the study were performed with Fisher exact test for categorical variables, t tests for continuous variables when the normality assumption was satisfied, and Mann-Whitney U test for continuous variables when the normality assumption as required for the t test was violated. Because the two groups were compared on a large number of characteristics, a more conservative threshold for significance (P<.01) was used instead of the conventional threshold of P<.05.
A mixed-effects model23 was used to examine the relationship between antenatal anxiety and depression subscale scores and gestational week to characterize the course of antenatal anxiety and depression across the whole period of pregnancy. This method was chosen because it accommodates subjects with unequal numbers of measurements at irregular time intervals.
Risk factors for antenatal anxiety or depression (defined as an anxiety or depression subscale score on the Hospital Anxiety and Depression Scale above the suggested threshold for a probable case of anxiety or depression) at each trimester were examined in two phases. In the first phase, demographic variables were considered in a logistic regression analysis with a forward stepwise variables selection procedure. In the second phase, a logistic regression was performed with the stepwise procedure performed on the psychosocial characteristics after force-entering those demographics significant in the first phase. The same analysis was performed to identify predictors of postpartum depression, but with antenatal anxiety and depression in each trimester instead of the psychosocial variables entered in the second phase. All estimates were accompanied by a 95% confidence interval (CI).
Of the 423 women invited to participate in the study, 357 agreed, yielding a response rate of 84.4%. Of these, 335 pregnant women (93.8%) completed all three antenatal time points, yielding an attrition rate of 6.2%. More participants dropped out after childbirth. The total number of participants who completed all the antenatal assessments and the 6-week postpartum assessment was 244, rendering a postpartum attrition rate of 27.2%. For analyses involving the antenatal time points (first trimester to third trimester) only, the final sample was 335. For analyses involving the postpartum time point, the final sample was 244. No significant differences on core demographic variables were found between those who participated in all the antenatal assessments and those who dropped out of the study before giving birth (Table 1). The two groups also did not differ on psychosocial characteristics at first trimester in terms of attitudes toward pregnancy, self-esteem, perceived social support, and marital satisfaction. Those who participated in all four time points and those who dropped out after giving birth were also not significantly different on core demographic variables examined or psychosocial characteristics at first, second, and third trimester. The two groups also did not differ on mean anxiety and depression scores at first, second, and third trimester.
The mean age of the antenatal sample (n=335) was 31 (standard deviation [SD] 4.8). Almost all of the women (95.5%) were either married or cohabiting, and 98.2% had attained at least a secondary level of education. More than half (60.1%) were primiparous, and 77.6% had planned for the pregnancy. Whether or not the pregnancy was planned, 97.0% of the pregnancies were wanted. Most (83.1%) of the women were never smokers, and 78.8% had no history of drinking. Nearly all were not smoking (96%) or drinking (95.8%) at the time of baseline assessment. None reported a history of past psychiatric disorders. Because too few participants reported current smoking, current drinking, and a history of psychiatric disorders, these were not further examined in subsequent analyses. The sample characteristics are summarized in Table 1. The mean weeks of gestation at which assessments were carried out were 12.5 (SD 1.2), 19.5 (SD 1.8), and 34.4 (SD 1.7) for first, second, and third trimester, respectively.
Table 1 also shows the characteristics of the sample with available antenatal and postpartum data (n=244). In general, the demographic characteristics of this sample were very similar to those of the antenatal sample.
The prevalence of antenatal anxiety and depression was characterized by a U-shaped curve, with both decreasing from first trimester to second trimester and then increasing again in the third trimester. Antenatal anxiety was more prevalent than depression. The prevalence of antenatal anxiety was 36.3% (95% CI 33.7–38.9%) at first trimester. The rate dropped to 32.3% (95% CI 29.7–34.9%) at second trimester but increased again to 35.8% (95% CI 33.2–38.4%) at third trimester. For antenatal depression, the prevalence was 22.1% (95% CI 19.9–24.4%) at first trimester. A slight drop in prevalence to 18.9% (95% CI 16.8–21.1%) was observed at second trimester, but the rate increased again to 21.6% (95% CI 19.4–28.9%) at third trimester. A total of 14.2% (95% CI 12.3–16.1%) had both antenatal anxiety and antenatal depression at first trimester. The corresponding comorbidity rates at second and third trimester were 12.6% (95% CI 10.8–14.4%) and 16.9% (95% CI 14.8–19%), respectively.
A lot of intraindividual instability in anxiety and depression across the three trimesters was observed. For anxiety, 17.8% of all the pregnant women had antenatal anxiety at all three time points, 15.4% had antenatal anxiety at two time points, and 20.8% had antenatal anxiety at one time point only. For depression, 6.9%, 11.2%, 19% had depression at three, two, and one time point, respectively. More than half (54%) of the women had anxiety at least once, and more than a third (37.1%) were depressed at least once.
The pregnant women were further categorized into the consistent/deteriorating problem group or the fleeting/no problem group. Women in the consistent/deteriorating group consisted of those who 1) screened negative in all three time points, 2) screened negative in the first trimester but positive in the second and third trimesters, and 3) screened negative in the first and second trimesters but positive in the third trimester. Those in the fleeting/no symptom group consisted of other women. For anxiety, 31.4% of the pregnant women were in the consistent/deteriorating group, whereas for depression, only 17.5% were in the consistent/deteriorating group. Women who were younger (OR 0.95, 95% CI 0.90–0.99, P<.05) and had a history of drinking (OR 2.09, 95% CI 1.13–3.87, P<.05) were more likely to have consistent/deteriorating anxiety symptoms. Those with a history of drinking (OR 2.37, 95% CI 1.20–4.70, P<.05) were more likely to have consistent/deteriorating depressive symptoms. In addition, being in the middle monthly family income category (20,000–30,000 Hong Kong dollars, which amount to approximately 2,564–3,046 U.S. dollars) was a protective factor. Being in a lower (below 20,000 Hong Kong dollars) income category increased the risk of having consistent/deteriorating anxiety symptoms (OR 2.39, 95% CI 1.18–4.81, P<.05), whereas being in an either lower or a higher income group (above 30,000 Hong Kong dollars) increased the risk of having consistent/deteriorating depressive symptoms (OR 3.14, 95% CI 1.22–8.06, P<.05, and OR 3.11, 95% CI 1.13–8.52, P<.05, respectively).
Mixed-effects model analyses were conducted to examine whether anxiety and depression scores changed significantly over the period of pregnancy. Results showed significant time effect with nonlinear association between time and anxiety/depression scores. More specifically, significant changes during the gestational period for both anxiety and depression, with a U-shaped relationship between gestational week and anxiety (P<.05) and depression (P<.05) scores, were observed. The lowest point of anxiety occurred in 23.72 weeks, with an anxiety subscale score of 5.86, whereas the lowest point of depression occurred in 24.48 weeks, with a depression subscale score of 4.93.
The results of univariable logistic regression analyses examining the association of maternal demographic factors with anxiety at each time point are presented in Table 2. Being younger (OR 0.94, P<.05), bearing the first child (OR 1.99, P<.01), history of smoking (OR 2.33, P<.01), and history of drinking (OR 2.53, P<.01) were significantly associated with an increased likelihood of anxiety at first trimester, whereas history of smoking (OR 1.87, P<.05) and drinking (OR 2.04, P<.01) were significantly associated with anxiety at second trimester. For the third trimester, younger age (OR 0.92, P<.01), history of smoking (OR 1.86, P<.05) and drinking (OR 2.27, P<.01) were associated with an increased risk of anxiety. In the multiple logistic regression analyses, history of drinking was associated with a nearly twofold increased risk of anxiety at first trimester (OR 2.30, 95% CI 1.29–4.10, P=.005) and second trimester (OR 2.16, 95% CI 1.21–3.87, P=.009), whereas being younger (OR 0.93, 95% CI 0.88–0.98, P=.007) and history of drinking (OR 1.86, 95% CI 1.03–3.37, P=.041) were associated with anxiety at third trimester.
Similar analyses were conducted for antenatal depression. The findings are summarized in Table 3. Of all the demographic risk factors examined, being single or divorced (OR 3.27, P<.05) and having a history of drinking (OR 2.00, P<.05) were significantly associated with an increased risk of depression at first trimester. Younger age (OR 0.92, P<.01) was associated with increased risk of depression at second trimester, whereas past drinking (OR 2.15, P<.05) significantly predicted depression at third trimester. For the multiple regression analyses, past drinking (OR 2.15, 95% CI 1.15–4.04, P=.017) was associated with a nearly twofold increased risk of depression at first trimester. Being younger (OR 0.92, 95% CI 0.87–0.98, P=.010) was associated with depression at second trimester, whereas both past drinking (OR 1.86, 95% CI 1.03–3.38, P=.041) and being younger (OR 0.93, 95% CI 0.88–0.98, P=.007) were associated with depression at third trimester.
To examine whether psychosocial factors could provide additional predictive power of antenatal anxiety and depression over and above that of demographic risk factors, a series of hierarchical multiple logistic regression analyses were conducted, with the effects of identified demographic risk factors controlled for. The results are summarized in Table 4. When a forward stepwise multiple logistic regression was applied to these psychosocial risk factors, low self-esteem was associated with an increased risk of anxiety at first trimester (adjusted OR 0.80, P<.001), second trimester (adjusted OR 0.82, P<.001), and third trimester (adjusted OR 0.81, P<.001). Low perceived social support was associated with an increased risk of anxiety at second trimester (adjusted OR 0.58, P=.030), and low marital satisfaction was associated with an increased risk of anxiety at third trimester (adjusted OR 0.62, P=.009). For depression, the results of multiple logistic regression indicated that unwanted pregnancy was associated with a more than sixfold increased risk of depression at first trimester (adjusted OR 6.51, P=.011). Low self-esteem was associated with increased risk of depression at first trimester (adjusted OR 0.89, P=.005), second trimester (adjusted OR 0.82, P<.001), and third trimester (adjusted OR 0.79, P<.001). Increased risk of depression was predicted by low perceived social support at first trimester (adjusted OR 0.59, P=.044) and third trimester (adjusted OR 0.46, P=.002). Low martial satisfaction was associated with increased risk of depression at second trimester (adjusted OR 0.60, P=.017).
A total of 244 women completed the 6-week postpartum questionnaire. Of them, 24.2% (59 of 244) scored above threshold on the Edinburgh Postnatal Depression Scale, indicating a high potential of having clinically significant postpartum depression. No demographic variables were needed to adjust for the postpartum depression analysis. Antenatal anxiety and depression in all three trimesters were associated with postpartum depression (antenatal anxiety: adjusted OR 2.66, 95% CI 1.36–5.20, P=.004 in first trimester; adjusted OR 3.65, 95% CI 1.89–7.07, P<.001 in second trimester; adjusted OR 3.84, 95% CI 1.92–7.65, P<.001 in third trimester; antenatal depression: adjusted OR 4.16, 95% CI 2.05–8.46, P<.001 in first trimester; adjusted OR 3.35, 95% CI 1.62–6.91, P=.001 in second trimester; adjusted OR 2.67, 95% CI 1.27–5.58, P=.009 in third trimester). Antenatal anxiety in late pregnancy and antenatal depression in early pregnancy were particularly powerful predictors of postpartum depression, increasing the odds by more than three times and more than four times, respectively. Those with consistent/deteriorating antenatal anxiety (adjusted OR 4.12, 95% CI 2.10–8.08, P<.001) or depression (adjusted OR 3.01, 95% CI 1.38–6.60, P<.01) had increased risk of postpartum depression.
Mental health problems in the antenatal period are much less recognized than those in the postpartum period. Our findings, however, showed that antenatal mental health problems are prevalent, with antenatal anxiety symptoms being even more prevalent than antenatal depressive symptoms. Indeed, more than half (54%) of our pregnant women had elevated anxiety at some point during their pregnancies, and more than a third of them (37.1%) had elevated depression. This underscores the need for greater attention to be paid to the mental health and well-being of pregnant women. This is especially important because we also found that comorbidity is common, with 12.6–16.9% of pregnant women having comorbid anxiety and depressive symptoms at various stages of pregnancy.
The strength of our study lies in the longitudinal assessment of both anxiety and depression across all three trimesters. Our data shows that antenatal anxiety and depression are not static but instead show a changing course, both in prevalence rates and in intra-individual anxiety and depression levels. Both conditions are more prevalent in early pregnancy and late pregnancy and less prevalent in the second trimester. A previous cross-sectional study using the Hospital Anxiety and Depression Scale also found a similar trend.24 It was, however, difficult to make conclusions from that study because the sample characteristics of the pregnant women assessed during the different trimesters were not compared and thus could potentially be different. Our longitudinal study provides evidence to confirm that such a U-shaped relationship between stage of pregnancy and anxiety and depression reflects the true state of affairs rather than being an artifact of methodological or sampling bias, especially given our extremely low attrition rate.
Intra-individual changes in both anxiety and depressive symptoms across different stages of pregnancy are characterized by a U-shaped curve, with the levels being lowest in the second trimester. Although previous studies demonstrated a generally increasing trend of psychological disturbances during pregnancy,12 a recent meta-analysis7 found a similar, but insignificant, trend for antenatal depression. We used a powerful and robust analytical tool, the mixed-effects model, and found that both anxiety and depression levels decreased from early to mid-pregnancy but increased again in late pregnancy.
Quite a substantial proportion of pregnant women had anxiety or depressive symptoms at only one or two time points. This shows that new cases of anxiety or depression or both can emerge in any trimester, implying that a one-time screening at any one antenatal visit only is not sufficient. Clinicians should be vigilant of potential cases of anxiety and depression emerging in different stages of pregnancy, with ongoing screening being done throughout. It is dangerous to exclude a case of probable antenatal anxiety or depression with information from only one antenatal visit.
With regard to identification of high-risk individuals, young age was found to be associated with antenatal anxiety and depressive symptoms. History of drinking was found to be one of the most significant risk factors, predicting anxiety symptoms in all three trimesters and depression in the first and third trimesters. It is not exactly clear why history of drinking is such a significant predictor, an area that definitely requires further investigation. Because drinking is generally not common among Chinese females,25,26 and a strong relationship exists between drinking behavior and psychological distress,27 it is possible that women with a history of drinking may have varying degrees of unrecognized and untreated psychological disturbance before pregnancy and, hence, are more prone to developing anxiety and depressive symptoms when faced with stressors associated with pregnancy. Alternatively, their anxiety and depressive symptoms may represent withdrawal symptoms resulting from alcohol abstinence during pregnancy.
Among psychosocial variables, self-esteem was the most predictive factor for anxiety and depression in all three trimesters. Our findings add to the accumulating body of evidence delineating self-esteem as a risk factor for antenatal anxiety13 by demonstrating that it is consistently associated with both anxiety and depressive symptoms across all stages of pregnancy. Pregnant women with low self-esteem are ill-equipped to face the multitude of developmental challenges and stressors of pregnancy and, thus, are more prone to anxiety and depressive symptoms throughout pregnancy. Given the salience of self-esteem as a risk factor across all stages of pregnancy, close monitoring of women with low self-esteem is warranted. Development of intervention for enhancing self-esteem to prevent antenatal psychological disturbances should also be encouraged.
Perceived social support and marital satisfaction have been identified as protective factors for antenatal anxiety and depression in the literature.13,14 Our study showed that their significance vary across different stages of pregnancy. Perceived social support protected against anxiety in the second trimester and against depression in the first and third trimesters. Marital satisfaction, on the other hand, protected against anxiety in the third trimester and against depression in the second trimester. The exact reason for this pattern of results requires further examination, but the general picture reflects that external resources are important, in addition to internal resources such as self-esteem. Unfavorable external factors place pregnant women at risk of psychological distress.
Unwanted pregnancy was found to be a significant predictor of depression only in the first trimester, increasing its risk by more than six times. Preliminary evidence in the literature showed that unwanted pregnancy places women under great psychological risks,14 but these studies did not examine its varying importance across different stages of pregnancy. Our study revealed that its significance decreases over time. It is possible that, initially, pregnant women with unwanted pregnancies found it hard to accept the reality, predisposing them to depression. However, as pregnancy progresses, the shock subsides and the bonding with the growing fetus strengthens, thus facilitating acceptance. Other factors, such as self-esteem, assume greater importance as the women grapple with ways to cope with the unwanted but real event.
Several implications are evident from our findings of risk factors for antenatal anxiety and depressive symptoms in different stages of pregnancy. First, we found that risk factors differ slightly in different trimesters, suggesting that anxiety or depression emerging in different stages of pregnancy might represent clinical problems with different pathogeneses. It is also evident from our findings that psychosocial factors play an important role, with significant predictive power even when the influence of demographic risk factors was controlled for. This highlights the need to attend to the pregnant woman’s psychosocial makeup, to assess this in determining her risk status, and to develop ways to improve her psychosocial resources to prevent or treat antenatal anxiety and depression.
Both antenatal anxiety and depressive symptoms predicted postpartum depression in our sample of pregnant women, further underscoring the importance of identifying and treating antenatal anxiety and depression. Previous studies mainly identified antenatal depression as a risk factor for postpartum depression although some studies also recognized antenatal anxiety as a risk factor.3,28 It is perhaps not surprising that depressive symptoms during pregnancy continue through to the postpartum period, but the salience of antenatal anxiety symptoms in predicting postpartum depression is somewhat unexpected. The association between antenatal anxiety symptoms and postpartum depression also increases as pregnancy progresses, with anxiety symptoms in late pregnancy being most strongly associated with postpartum depression. We do not know the exact nature of the anxiety experienced by pregnant women, but it is possible that their anxiety is anticipatory in nature, arising out of perceived inadequate resources to cope with the challenges of pregnancy and motherhood. Women who are still anxious in the final trimester are those with most difficulty in adjusting to the maternal role and least confidence in meeting the demands of motherhood. In the postpartum period, the demands took on real form. Instead of being anxious about impending challenges, they became depressed by their inability to grapple with the real demands of motherhood. More qualitative studies of the exact nature of antenatal anxiety would better inform us about the mechanisms underlying its relationship with postpartum depression. Nevertheless, preventing, identifying, and treating both antenatal anxiety and antenatal depression should be made a priority in efforts to prevent postpartum depression.
We attempted to characterize a group of pregnant women who deserve particular clinical attention as compared with those with consistent or deteriorating anxiety or depressive symptoms. Our analyses showed that this group tended to be younger, to be in the middle income range, and to have a history of drinking. Women with these risk factors certainly require close clinical monitoring and frequent assessment for anxiety and depressive symptoms, especially since they were also found to be more prone to postpartum depression.
Our study has several limitations. First, there is no good local data concerning the prevalence of anxiety and depression in women of childbearing age for comparison. It is therefore difficult to tell whether the rates of depression and anxiety are higher in pregnant women than among non-childbearing women of similar ages. Further studies should try to include matched controls to detect whether there are differences. Second, we used only self-report screening tools to assess antenatal anxiety and depressive symptoms. Scoring above the cutoff score only indicates that the individual is a “probable case of anxiety or depression.” To get more accurate estimates of the prevalence of these problems, follow-up clinical interviews with the identified cases should be performed in future studies. However, because we used the Hospital Anxiety and Depression Scale, which has very good sensitivity and specificity values, our estimates should have considerable validity.
Notwithstanding these limitations, our study serves as an important step toward recognizing the dynamic nature of anxiety and depression across different stages of pregnancy. We also identified history of drinking, young age, low self-esteem, low perceived social support and marital satisfaction, and unwanted pregnancy as risk factors for antenatal anxiety and depressive symptoms. Finally, our study also points to the need for greater research and clinical attention to the much neglected but common clinical problem of antenatal anxiety. It is time to shift our emphasis from the postpartum period to the antenatal period and to shift our focus from depression to anxiety.
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