Pregnancy is a significant life event during which women need to restructure their life goals, behaviors, and responsibilities to achieve the integration of a new self-image [1], thereby making pregnancy and motherhood inherently stressful. From the perspective of interactionist models, this can have varying consequences, positive or negative, for both the mother and the newborn child, depending on the person-environment interaction [1]. Considering this perspective, Lazarus and Folkman’s transactional model of stress and coping has been used as an explanatory model in studies of pregnancy and motherhood [2, 3]. Due to the impact that pregnancy and postpartum have on women’s health, understanding the psychosocial variables influencing pregnancy is a relevant topic in global public health. These models, which consider the person as an active agent in their own health, emphasize two fundamental psychosocial processes: individual’s perception of the stressful stimulus and their coping processes [4]. The present study integrates two perceptual variables (i.e., locus of control (LoC) and maternal competence) and a coping mechanism (non-adaptive emotional coping) into a model that assesses psychological processes from early gestation until four months after delivery. To the best of our knowledge, while the role of the aforementioned variables have been studied independently in the context of pregnancy and motherhood, there are no known studies integrating their combined influence on the outcomes of this stressful situation, such as of postpartum depression (PPD) [5]. Specifically, the changes associated with pregnancy and motherhood require an adjustment process that is challenging for many women [6, 7], potentially leading, in some cases, to the development of PPD [8]. This can lead to feelings of sadness, fatigue, irritability, and a sense of inadequacy in coping with new maternal responsibilities [9], as previous research has indicated a strong association between symptoms of PPD and low perception of maternal competence [10, 11].

Within the interactionist models previously discussed, LoC has received considerable attention as a mediating variable between stressors such as motherhood, perceived stress (cognitive appraisals of the situation), and their consequences [12, 13]. This variable is particularly significant in the present context, as the experience of pregnancy challenges beliefs about control over health and increases perceived stress related to childbearing [14]. According to Rotter’s reformulation [15], LoC reflects a gradient wherein individuals expect varying degrees of control over their own lives. Specifically, individuals with an internal locus of control believe that their outcomes are determined by their own actions and decisions, whereas individuals with an external locus of control (ELoC) attribute their life events to external factors such as luck, chance, or other unspecified forces. Previous research on locus of control during pregnancy has identified associations of external locus of control with higher perceived stress [16, 17], unhealthy behaviors such as smoking or alcohol consumption [18, 19], preterm delivery [17], neonatal death [19], and pain during pregnancy [20]. Moreover, regarding emotional symptoms, ELoC seems to be a predictor of anxiety [21, 22], as well as both prenatal and postpartum depression [23]. The extensive research on this field suggests that prior assessment of control beliefs about pregnancy is considered essential for planning effective interventions to prevent depression during gestation and in the postpartum period [12, 13].

Another cognitive variable of interest in pregnancy and motherhood is maternal competence, recognized as a significant factor that mitigates the impact of perceived stress during pregnancy, allowing for the acquisition of caregiving behaviors, and contributes to the psychosocial development of the infant [24, 25]. Perceived maternal competence refers to an individual’s set of beliefs their ability to meet the demands of parenting and to develop adequate parenting skills [26, 27]. Increased competence promotes persistence in caregiving tasks, thereby mitigating feelings of guilt or frustration, while perceptions of incompetence appear to significantly predict depressive symptoms during initial interactions between the mother has and her baby [28]. Thus, women who feel insecure and perceive their personal resources as insufficient to meet the demands of their baby tend to attribute negative meaning to motherhood and, increasing their susceptibility to experiencing PPD [29]. However, PPD could also impair maternal ability to care for the infant [30], creating a vicious circle that is difficult to break.

From the perspective of the interactionist models of stress discussed earlier, coping strategies play a fundamental role in the perceived outcomes of a stressful situation [4]. The diathesis-stress model defines coping strategies as the cognitive and behavioral efforts individuals employ to manage or minimize the impact of stressful situations, this positioning coping strategies as a fundamental pillar of psychological well-being [4]. Among the different strategies, a distinction is made between emotion-focused and problem-based strategies depending on the objective (e.g., minimizing the unpleasant emotion or solving the problem, respectively). These strategies can be either adaptive or maladaptive, depending on their consequences for the individual. Emotion-focused coping is usually employed when a woman feels significant distress regarding the new circumstances of motherhood [31, 32], which is why it has been associated with a considerable increase in the risk of postpartum depression [33]. Specifically, emotional coping strategies such as denial, guilt, or avoidance stand out as significant predictors of depression during pregnancy [34, 35] and are associated with problems in child development [36, 37], thus being considered as non-adaptive. Conversely, adaptive coping strategies such as positive reappraisal and acceptance are associated with positive emotional states during pregnancy [38].

To the best of our knowledge, no studies have examined the role of non-adaptive emotional coping strategies as mediating variables between external locus of control and PPD, integrating all these variables at different times during pregnancy and the postpartum period. In addition, little information is available on the effect of maternal competence on these associations to guide the appropriate adaptation to motherhood. Recent research highlights the need to delve deeper into variables related to women’s personality [39]. As the previous literature suggests, studying the combined effects of ELoC, coping strategies for managing stress related to childbearing, maternal competence and postpartum depression is essential for understanding and supporting mothers during this critical process. In addition, identifying risk factors associated with gestation and/or postpartum could facilitate the development of programs promoting healthy coping strategies that contribute to the well-being of mothers and their babies. Therefore, the first aim of the current study was to explore the predictive effect of ELoC assessed in the first-trimester of pregnancy, on PPD assessed four months after delivery, and on the mediating role of non-adaptive emotional coping assessed during the third-trimester of pregnancy. Following this model, the second aim was to examine the effect of maternal competence evaluated in the postpartum period on the relationship between non-adaptive emotional coping and PPD, as well as on the relationship between ELoC and PPD.

The present study aims to explore, from an interactionist perspective, the mediating role of maladaptive emotional coping strategies in the relationship between external locus of control and PPD, while considering the possible moderating role of maternal competence. Our results suggest that external locus of control is associated with increased use of non-adaptive emotional coping strategies, which in turn contributes to greater symptoms of postpartum depression. Interestingly, these associations may weaken in the presence of moderate and high levels of perceived maternal competence.

In relation to the first aim of the present study, ELoC predicted the occurrence of PPD through the mediating effect of non-adaptive emotional coping strategies. This type of coping can manifest in specific behaviors, such as maladjusted and uncontrollable expressions of negative emotions, including confrontation and anger towards other people. Previous studies have shown that this type of coping can lead women to adopt strategies based on guilt and resignation, thereby potentially exacerbating depressive symptoms [55]. Similarly, previous research has identified a relationship between external locus of control and PPD [22]. These results align with studies suggesting that mothers with an external locus of control exhibit less persistence in addressing parenting challenges, take less responsibility for the infant’s health status, refrain from seeking information, have lower tolerance for delays in the neonatal development, and consequently, may experience less success in effective parenting [56]. This shows the importance of examining the perceived lack of control during pregnancy, as it may hinder the adjustment to motherhood and prevent emotional disorders during pregnancy or postpartum [23]. Similarly, previous research conducted with low-risk pregnant women suggested that coping styles varies throughout pregnancy, with (non-adaptive) emotional coping being the style most associated to depressive states [38, 57, 58]. Our results show that the longitudinal assessment of prenatal coping is particularly relevant in highlighting effective strategies that reduce maternal postpartum depression and contribute, in turn, to maternal-infant well-being.

The prenatal period presents an opportunity for early identification of risk factors to help prevent PPD, supported by previous studies indicating that depression during pregnancy is one of the most significant predictors [59, 60]. Indeed, our data corroborate the role of prenatal emotional symptoms in predicting postpartum depression within the simple mediation model considered (external locus of control $\to$ emotional coping $\to$postpartum depression). However, a particular noteworthy finding in our results is that the significance of anxiety and depression symptoms (included as covariates) diminishes significantly when maternal competence is introduced as a moderating variable in the proposed mediation model (moderated mediation model: ELoC $\to$emotional coping $\to$PPD, considering the conditional effects of maternal competence). This means that when a positive psychological variable (i.e., maternal competence) is introduced into the model, prenatal emotional symptoms are no longer a significant predictor. Another novel aspect of this study lies in the mechanism of action exerted by maternal competence in reducing postpartum depression. Specifically, it is interesting that the effect of ELoC on PPD through the use of non-adaptive emotion-based strategies is attenuated only at moderate or high levels of perceived maternal competence. The relationship between low maternal self-efficacy and postpartum depression has been extensively studied [28, 29]. Previous literature has highlighted that the feelings of incompetence, reflecting a mother’s perception of insecurity in her maternal role, seems to mediate the relationship between her interaction with the infant and depression [28, 61]. Our data provide additional information into the buffering role of maternal competence on other variables traditionally considered as risk factors for postpartum depression (i.e., external locus of control, non-adaptive emotional coping).

In our opinion, our results have important clinical implications for low-risk pregnant women. This study examined the influence of external locus of control and emotional coping on the occurrence of PPD in a longitudinal descriptive relationship-seeking study, from the beginning of pregnancy until four months after delivery. External locus of control combined with non-adaptive emotional coping are shown to be clear risk factors for PPD. According to the transactional model of stress and the cognitive diathesis-stress model of depression, psychological vulnerability factors such as perception and coping interact with stressful events to increase the likelihood and/or occurrence of depression [62, 63].

Of special relevance is the buffering role of the maternal competence against the negative effects of the aforementioned variables (e.g., ELoC, emotional coping). In clinical contexts, studies with pregnant women suggest that maternal identity integration is a protective factor for PPD. This is due to the observed relationship between depression and feelings of being a “bad mother”, stemming from perceptions of neglect and inadequate care toward their children [10]. One personal resource that may enable women to negotiate motherhood competently and adaptively is acquiring a repertoire of behaviors to regulate emotions such as guilt or frustration, and addressing cognitive factors that might interfere with infant care. From the theoretical framework of maternal role attainment [64, 65] our study underscores the importance of working on maternal competence through behavioral modification to mitigate the effects of PPD. From this perspective, various psychological interventions have focused on improving competency beliefs through techniques aimed at reducing maladaptive behaviors and promoting healthy ones [66, 67]. Therefore, implementing programs aimed at improving self-efficacy during pregnancy seem particularly relevant, with further research needed to explore optimal interventions and associated contextual variables, given insufficient results regarding the long-term efficacy of interventions for pregnant women predisposed to PPD [66, 67, 68]. In this regard, prenatal education programs can be useful in providing the knowledge on skills and risk factors that can help pregnant women prevent PPD. Bringing together midwives, nurses, and other health providers can facilitate the establishment of consistent procedures for assessing past and present psychosocial stressors that may affect women’s health from the first-trimester of pregnancy through the postpartum period.

The present study has certain limitations to be considered. Firstly, the small sample size and recruitment from a single hospital limit the generalization of the results obtained. Nevertheless, our research design, which incorporates measurements at three different points in time, allows us to explore various predictors of PPD across different stages of the perinatal period, although future research should incorporate additional variables. Secondly, the data obtained relies on self-report measures, which are subject to well-known limitations such as response biases influenced by the participants’ desire to present themselves favorably. Regardless, the measures used in our study demonstrate good psychometric properties. Lastly, the perception of maternal competence may be influenced by socio-demographic, ethnic, and cultural variables that were not included in this study. Regarding the sample size, the observed attrition may introduce bias in interpreting consistent results over time, although similar studies using the same methodology also reported similar sample losses [41, 42].

Despite the previous limitations, our results support the mediating effect of the use of non-adaptive coping strategies, in this case emotional, between the external locus of control and postpartum depression. Previous literature points out the relationship between external locus of control and depression, but research on the influential mechanisms is less abundant, especially in the case of maternal mental health. Thus, the detection and intervention of non-adaptive strategies during stressful situations such as pregnancy and motherhood appears to be a proactive approach in the promoting of maternal health. On the other hand, regarding protective factors, beliefs of competence as a mother play a clearly buffer the effects of external locus of control on postpartum depression through maladaptive coping. These results are of special relevance considering the prospective nature of the research and the finding that prenatal anxious-depressive symptoms (covariates) did not significantly influence the proposed moderated mediation model. Therefore, promoting maternal competence can serve as a positive resource for reducing postpartum depression and supports the transition to the maternal role as an integrated part of one’s own identity.

The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

LGH participated in conceptualization, data curation, investigation, methodology, resources writing—original draft, supervision and validation. PCM participated in conceptualization, methodology, resources, data curation; writing—original draft preparation. CÉG participated in conceptualization, methodology, resources, data curation; writing—original draft preparation. CPP participated in conceptualization, data curation, formal analysis, investigation, methodology, writing—original draft, writing review and editing. All authors read and approved the final manuscript. All authors have participated sufficiently in the work and agreed to be accountable for all aspects of the work.

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. The study was approved by the Bioethics Committee of Fuenlabrada University Hospital in Madrid, Spain. Written informed consent was obtained from all participants.

The authors gratefully acknowledge all the participants for their collaboration and enthusiasm. We thank Dr. Dolores Marín for her invaluable collaboration in the initiation of this research.

This work was supported by the Health Research Fund (Fondo de Investigaciones Sanitarias, FIS), Instituto de Salud Carlos III (Spain) (Reference PI07/0571).

The authors declare no conflict of interest.