|
 
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| DR. BUCKSHEY AWARD PAPER |
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| Year : 2018 | Volume
: 23
| Issue : 1 | Page : 12-18 |
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Does prenatal maternal stress affect the outcome of pregnancy? A prospective study from North India
Jitender Aneja1, Bir Singh Chavan2, Jasmin Garg2, Anju Huria3, Poonam Goel3
1 Department of Psychiatry, All India Institute of Medical Sciences, Jodhpur, Rajasthan, India
2 Department of Psychiatry, Government Medical College and Hospital, Chandigarh, India
3 Department of Obstetrics and Gynaecology, Government Medical College and Hospital, Chandigarh, India
| Date of Web Publication | 2-Nov-2018 |
Correspondence Address:
Jitender Aneja
Department of Psychiatry, All India Institute of Medical Sciences, Jodhpur, Rajasthan
India
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/jmhhb.jmhhb_55_17
Background: The impact of prenatal maternal stress on the outcomes of pregnancy has been investigated previously but with contradictory findings. Only few studies have evaluated the association of pregnancy-specific anxiety with preterm birth (PTB) and low birth weight (LBW). In addition, minimal research in this aspect is available from low- and middle-income countries. Aim: The study investigated the association of anxiety (in general and pregnancy-specific), depression, and stress with the outcomes of pregnancy in terms of PTB and LBW. Materials and Methods: It was a prospective study in which 110 antenatal mothers in the first to third trimester of pregnancy were evaluated on perceived stress scale-14, pregnancy-related anxiety scale, state trait anxiety inventory, and Beck depression inventory. The participants underwent single assessment on these tools, and the outcomes of pregnancy were retrieved either from medical records or through telephonic enquiry. Results: The presence of pregnancy-specific anxiety, perceived stress, and depression did not affect the outcome of pregnancy. However, participants with trait anxiety were at higher risk of delivering a preterm baby (odds ratio = 4.08; confidence interval = 0.79–20.91) although the effect was small. None of the sociodemographic or obstetrical clinical variables associated with the outcomes of pregnancy. Conclusion: Although stress and anxiety were quite prevalent in our cohort, it did not impact the outcomes of pregnancy.
Keywords: Anxiety, depression, pregnancy, stress
How to cite this article:
Aneja J, Chavan BS, Garg J, Huria A, Goel P. Does prenatal maternal stress affect the outcome of pregnancy? A prospective study from North India. J Mental Health Hum Behav 2018;23:12-8 |
How to cite this URL:
Aneja J, Chavan BS, Garg J, Huria A, Goel P. Does prenatal maternal stress affect the outcome of pregnancy? A prospective study from North India. J Mental Health Hum Behav [serial online] 2018 [cited 2023 Jun 4];23:12-8. Available from: https://www.jmhhb.org/text.asp?2018/23/1/12/244917 |
| Introduction | |  |
Prenatal maternal stress, conceptualized to be a multidimensional entity, results from imbalance between environmental demands and individual resources and leads to increased stress perception and maladaptive coping. This may in turn lead to adverse mental health consequences such as anxiety and depression in the mother and promotes unhealthy behavior during pregnancy.[1] Physiologically, prenatal maternal stress may lead to activation of the hypothalamic–pituitary–adrenal axis and increased maternal glucocorticoids that in turn is associated with negative birth outcomes.[2]
Preterm birth (PTB) and low birth weight (LBW) are two common adverse outcomes of pregnancy that increase neonatal mortality in high- and low/middle-income countries (LMICs) equally.[3] PTB is defined as birth before 37 weeks (259 days) of gestation which is further categorized into <28 weeks, 28–<32 weeks, and 32–<37 weeks across different studies and a weight of < 2500 g at birth is considered as LBW.[4],[5] Global estimates for LBW are nearly 15.5%, and 95% of them are born in LMIC. The prevalence estimates for LBW in India are up to 36.5% and nearly 13% of these were PTB.[5],[6]
The relationship of prenatal maternal stress (measured in terms of anxiety, depression, and perceived stress) and the outcomes of pregnancy has been evaluated previously.[7],[8],[9],[10],[11] Although some of the studies exhibited an association of prenatal maternal stress, especially in terms of depression and stress with PTB and LBW, while that for anxiety and pregnancy outcomes is inconclusive. Further, it was suggested that pregnancy-specific anxiety might be a better measure than general anxiety in predicting this association.
Pregnancy-specific anxiety has been conceptualized as a distinct syndrome characterized by fears about the health and well-being of one's baby, process of childbirth and postpartum, hospital and healthcare experiences, and maternal role.[12] A relatively new attribute, pregnancy-specific anxiety is considered to be similar to state anxiety. Although meager research linking pregnancy-specific anxiety with birth outcomes is available from geographically different areas, it is riveting.[13] Further delineation of the intricacies of relationship between prenatal maternal stress, especially pregnancy-specific anxiety with outcomes of pregnancy, may assist in early detection of stress in this vulnerable population and preventive strategies, or early intervention may reduce morbidity.
Most of the available research in this field was conducted in high-income group countries and minimal in the developing nations.[3],[14],[15],[16] Because the sociodemography, economy, family and cultural practices, and health-care systems are different in the high-income countries and LMIC, the findings cannot be generalized. In addition, Indian sociodemographic and family systems are rapidly changing owing to economic growth and various other factors. Hence, this provided us impetus to undertake this research that aimed at evaluation of impact of prenatal maternal stress on the outcomes of pregnancy. It was hypothesized that prenatal maternal stress (in terms of anxiety in general and pregnancy-specific in particular, perceived stress, and depression) shall be associated with PTB/LBW.
| Materials and Methods | | |
Study design and procedures
Initially, we evaluated the prevalence of stress and its psychological correlates in pregnant women (published recently),[17] and the cohort was then followed-up for the assessment of outcomes of pregnancy. The Departments of Psychiatry and Obstetrics of a tertiary care multispecialty teaching hospital in Chandigarh collaborated to conduct this prospective research. Initially, the participants were enrolled during the period June 1, 2015, to August 31, 2015, and underwent cross-sectional evaluation for sociodemographic or obstetrical clinical variables and measures of stress. Inclusion criteria for initial study were consenting antenatal women in the first to third trimester of pregnancy, with single fetus, confirmed by obstetrical examination and ultrasonography, while those with multiple pregnancies, complications of pregnancy (severe medical-surgical or psychiatric illness), physical handicap, and who suffered a major stressful life event in 6 months before conceiving (e.g., death of spouse or a close family member, marital separation or divorce, and conflicts over dowry) were excluded. The participants were again contacted telephonically from January 1, 2016, to May 30, 2016, as by this time all of them would have delivered. In addition, medical records of patients, who delivered at the study center, were used to extract data related to outcomes of pregnancy. An additional ethical clearance was sought from the Institute's Ethical Committee.
Study instruments
In addition to sociodemographic and obstetric evaluation, the participants were assessed on the perceived stress scale-14 (PSS-14),[18] pregnancy-related anxiety scale (PRAS),[19] state trait anxiety inventory (STAI),[20] Beck depression inventory (BDI),[21] and a coping inventory. Reassessment of the study participants on these tools was not done during pregnancy or after delivery. Although the tools have been described in detail in the previous paper,[17] for a better understanding of the reader, a brief description of instruments relevant to present study is provided here.
Perceived stress scale
We used the 14-item PSS in the initial study that is a self-report questionnaire in which each item is scored on a Likert scale from 0 to 4 (0 = never, 1 = almost never, 2 = sometimes, 3 = fairly often, and 4 = very often). It is a measure of global stress, and higher scores indicate higher perceived stress. The scale was translated to Hindi using the WHO guidelines[22] and the reliability analysis of scale showed Cronbach's alpha value of 0.729 for the negative scale and 0.650 for the positive scale. We did not validate this translated version of PSS-14.
Pregnancy-related anxiety scale
PRAS is a 10-item self-report questionnaire that asks women to report the frequency or extent to which they were worried or felt concerned about their health, their baby's health, labor and delivery, and caring for baby. There are five items about childbirth (PRASa) and rest of five items about one's own health and delivery (PRASb). The items are rated on a Likert scale ranging from 1 (never or not at all) to 4 (a lot of the time or very much) and reverse scoring for two items. We used a cutoff of >20 for significant pregnancy-related anxiety though lower cutoff of 10 has also been used. This scale was also translated to Hindi and the Cronbach's alpha for this was 0.725.
State-trait anxiety inventory
This 40-item scale provides reliable, relatively brief, self-report measure of state (A-S) and trait (A-T) anxiety. It has been previously used in studies done in antenatal mothers with high concurrent validity is such samples. A validated, vernacular translation of STAI is also available that was used in this study.[23]
Beck depression inventory
BDI is a widely used self-rated questionnaire having 21 items, six of which are somatic/biologic type. For this study, the Hindi version of the scale, which is available, was used. The Hindi version has recently been validated with omission of five items.[24] However, we did not omit any item, and the Cronbach's alpha for the translated tool in our study sample was 0.771.
Statistical analyses
Statistical analyses were performed using the Statistical Package for the Social Science Version 14 (SPSS Inc. Released 2005, SPSS for Windows, Version 14.0, Chicago). Kolmogorov–Smirnov test was used to assess the normal distribution of data. Continuous variables were computed in terms of mean and standard deviation (SD), and frequencies were measured for the categorical variables. Comparisons of the sample in terms of delivery outcomes (i.e., period of gestation [POG] and birth weight of baby) were done using Student's t-test, and Pearson's Chi-square test with Yate's correction and Fisher's exact test where applicable. Binary logistic regression was carried out to look for association of various measures of stress and outcomes of pregnancy.
| Results | | |
A total of 110 pregnant women from the first to third trimester of pregnancy were evaluated at the initial stage. Out of 110 participants, we could get the details of delivery for 92 pregnant women, with an attrition of 16.36% at follow-up. Sixty-four women (73.0%) had delivered at our center, 14 (16.10%) gave birth to their child at other government hospitals in the same city, while 9 (10.30%) delivered at private centers. Four of the participants had abortion due to congenital defects in the fetus and one stillbirth occurred due to development of hydrocephalus. Hence, the final data consisted of outcome details of 87 pregnant women.
Sociodemographic profile of participants
All the participants were married, mostly unemployed and homemakers, educated up to or beyond graduation, did not earn living for themselves or earned < 5000 (INR) per month, with more than half being Hindu who lived in urban areas [Table 1]. | Table 1: Association of sociodemographic or obstetric variables and outcome of pregnancy
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Clinical profile and pregnancy outcomes
As shown in [Table 1], the mean age of participants was 26.33 (SD = 3.71) years, more than half of participants had maiden pregnancy and were in second trimester (44.8%), and nearly one-fourth of participants had a history of previous abortion. Seventy-eight (89.6%) participants delivered a full-term baby (POG >37 weeks), with nearly half of these delivered vaginally. The birth weight was <2.5 kg in 26 (29.9%) babies while rest (n = 61; 70.1%) had normal weight (>2.5 kg). The mean scores of participants on PRASa, PRASb, PRAS total, and PSS were 10.21 (±2.54), 7.97 (±2.92), 18.19 (±4.73), and 25.96 (±5.48), respectively. Similarly, the mean scores of state, trait anxiety, total STAI, and BDI were 34.83 (±7.23), 41.08 (±5.54), 75.77 (±11.81), and 4.52 (±4.25), respectively.
We examined the relationship of various sociodemographic or obstetric clinical variables and measures of stress [Table 1], [Table 2], [Table 3]. For this purpose, the groups were classified according to the POG (whether <37 weeks or ≥37 weeks) and the birth weight of baby (<2.5 kg or ≥2.5 kg). No significant association for most of the sociodemographic and obstetrical clinical variable with outcomes of delivery was found except that the individuals who had trait anxiety were four times more likely to have a POG < 37 weeks. However, the Chi-square test (2.08/P = 0.07) for the association of trait anxiety with POG was not significant. Bivariate logistic regression was utilized to examine the association of term/preterm delivery and normal/LBW with the measures of stress, anxiety (general and pregnancy-specific), and depression. Again, the presence of trait anxiety significantly predicted PTB (B = 0.507, standard error = 0.891, P = 0.039). | Table 2: Relationship between measures of stress, anxiety, depression, and the outcomes of pregnancy
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 | Table 3: Association between measures of antenatal stress and outcomes of delivery using odds ratio with 95% confidence interval
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| Discussion | | |
The present research explored the effect of a relatively less studied attribute, i.e., pregnancy-related anxiety in addition to the traditional measures of stress, anxiety, and depression and their impact on the outcome of pregnancy. Although anxiety specifically related to pregnancy is conceptually akin to state anxiety, researchers have proposed that this attribute captures both the character traits and the environmentally influenced states. Dunkel Schetter[13] suggested that women with pregnancy-specific anxiety tend to have infertility and unplanned pregnancies and are vulnerable to a range of psychosocial factors which in turn influence the hypothalamic–pituitary axis and thus impact the outcomes of pregnancy.
The earliest study[25] evaluated the influence of pregnancy-related anxiety in 90 sociodemographically homogenous group of antenatal mothers on the outcomes of pregnancy and had reported the association of former with LBW but not with gestational age. Later on, the same group developed the PRAS[19] and found that it also affected the POG. Although some other groups of researchers evaluated as well as developed tools to measure anxiety specific to pregnancy, studies for its relationship were not performed till late. Lobel et al.[26] evaluated the role of pregnancy-specific stress as well as other measures of stress in predicting the outcome of pregnancy. Two hundred and seventy-nine antenatal mothers were assessed at three different points during pregnancy. After controlling for confounding factors, and utilizing a structural equation model, it was concluded that pregnancy-specific stress was a better predictor of pregnancy outcome in comparison to perceived stress, state anxiety, or life event stress. Similarly, a Canadian-nested case–control study,[27] which analyzed pregnancy-related anxiety as well as various other measures of stress, reported only former to be independently associated with spontaneous PTB (odds ratio [OR] = 1.8, confidence interval [CI] = 1.3–2.4). In contrast, two other studies did not find any association of pregnancy-related anxiety with PTB or gestational age.[28],[29] In a recent study from Iran,[16] which used pregnancy distress questionnaire (PDQ), it was reported that concerns about emotions and interpersonal relationships (a part of PDQ) significantly predict the weight of infant and the APGAR score. The prevalence of pregnancy-specific anxiety in the present study stood at nearly 21%,[17] but no association with the outcome of pregnancy in terms of POG or LBW was observed.
With respect to the association of anxiety in general and its association with PTB, the result of index study is in accordance with some of the previous studies. In one of the earliest studies[30] that evaluated 1515 antenatal women at four different POG using general health questionnaire (GHQ), neither anxiety nor depression was associated with PTB. Similarly, two other studies did not report any association of anxiety in general and the outcomes of pregnancy.[3],[31] However, in an American study,[32] positive association of state and trait anxiety with PTB was found, while only trait anxiety predicted PTB in another research.[33] But, we found a significant association of trait anxiety and LBW in contrast to most of earlier research.[33],[34],[35],[36] Although one more study found association between anxiety and LBW in multipara women, anxiety was measured on GHQ (a score of >3).[37] The finding in our study could have been confounded by a range of factors such as small number of participants, multiple measures to assess related attributes, and nonadjustment of sociodemographic factors.
The relationship of stress and its impact on the outcomes of pregnancy as well as complications has been studied in a large number of studies.[37],[38],[39],[40] Most of the these utilized measures of stress in form of major life events scale, perceived stress, psychosocial adversities or job stress. In addition, majority of such studies had evaluated anxiety and depression, social support, and functioning along with stress.[3],[15],[19],[25],[26],[27],[28],[29],[41],[42],[43],[44],[45] The available research has shown that perceived stress during pregnancy could predict PTB with OR in the range of 1.12–2.45.[11] In addition, stress has also been shown to predict LBW with higher risk in women undergoing chronic stress.[10],[46],[47] Faisal-Cury et al. (2010)[3] used the clinical interview schedule-revised to measure the prevalence of neurotic and stress-related common mental disorders (CMDs) and their impact on PTB and LBW. Although the prevalence of CMD in their study was 33.6%, no association of sociodemographic or obstetrical clinical variables and CMD was found on PTB or LBW. In the index study also, the prevalence of stress was nearly 31%,[17] but no association of stress was found with PTB or LBW.
Depression during pregnancy has been shown to affect its outcomes as well as lead to various complications in more than a dozen studies.[11],[48],[49],[50],[51] The risk of PTB in depressed pregnant women has been shown to be in range of 1.07 (CI = 0.87–1.31) to up to 3.39 (CI = 3.24–3.56), while the risk of LBW ranges from 1.4 to 2.9 times in studies from developing countries and 1.2 times in the USA.[9],[11] One of the earlier Indian studies evaluated 250 antenatal mothers for depression and reported higher risk (OR = 1.44) of LBW in depressed mothers.[14] Similarly, a recent study from Taiwan found depressive symptoms at 25–29 weeks of gestation to be associated with PTB.[15] However, some other studies have not found any association of depression during pregnancy and PTB/LBW.[3],[52],[53] We also could not find any association of depression with outcomes of pregnancy, which is largely due to lower number of participants fulfilling the criteria of depression and partly due to nonadjustment for many confounders.[17]
To summarize, the evidence for impact of stress, anxiety (general and pregnancy-specific), and depression is conflicting for its association with various pregnancy-related outcomes. Research in this field is minimal from India, and through this study, we add on to the evidence for relationship between various measures of stress during pregnancy and its association with PTB/LBW. However, the index study is limited by small sample size, exclusion of high-risk pregnancies, utilization of assessment tools to evaluate various constructs rather than diagnostic interviews, conduction of research at tertiary care hospital, and high attrition rate at follow-up.
| Conclusion | | |
Considerable amount of research is available that has established the adverse effects of stress, anxiety, and depression during pregnancy. However, it is still unknown how much role each of these factors contributes. Furthermore, the effect of pregnancy-specific anxiety on the mental health of antenatal mothers and their fetuses is still evolving. Hence, it will be interesting to take up further research that can elucidate the interaction of various socioeconomic and cultural factors, affective state of antenatal mothers, and their influence on the outcomes of pregnancy as well as latter development of the child. This in turn will help us in early identification of at-risk expecting mothers and evolve strategies to intervene suitably.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3]
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