Pregnancy, childbirth, and becoming a mother are challenging experiences that require adaptive responses from the mother in order to maintain mental health, establish a relationship with the infant, and adapt to a new role [1]. According to Mercer (2004), maternal role adaptation is characterized by “an event in which the mother becomes attached to the infant and feels harmony, self-confidence, competence, pleasure, and satisfaction from performing the tasks related to child care and the creation of maternal identity” [2]. The first year after childbirth is the most challenging period in the process of adaptation to the maternal role, especially for new mothers [3], and during this period, a woman begins to attach the maternal role to her personality [4].

Maternal role is influenced by many factors including variables related to the mother, the child, and the social environment. Furthermore, the mother's problems in balancing her roles as a wife, a mother, or even an employee, are related to her general sense of incompetence, and role conflict is the most important predictor of maternal role acquisition in this regard [5]. Given the close relationship between a child's physical and psychological health and the mother's health, promotion of the mother's mental health can have an effective role in protecting the health of family and the community [6]. For mothers who do not have proper adaptation with their role, they will have reduced maternal function, especially with regard to their attachment to the child, and thus the risk of exposing the child to developmental delays increases accordingly [7]. Since infant development is sensitive to the quality of mother-infant interaction, infancy (0–12 months) is a good time for health care providers to assess and improve maternal role adaptation [8]. The implementation of interactive and reciprocal interventions by health care professionals is one of the most important ways to foster maternal role acquisition [9].

Although it is argued that parenting interventions as initial preventive interventions are ineffective for children with mild behavioral problems [10], a review article showed that parent training programs have positive effects on the psychosocial wellbeing and empowerment of parents in terms of developing secure attachment, enhancing parental reflective functioning during infancy and toddlerhood, and co-parenting relationship [11]. In this regard, previous studies have revealed that training and counseling have an important effect on promoting motherhood and the process of caring for the baby [12,13], and some studies have provided evidence for the impact of using such methods as self-efficacy and self-confidence promotion strategies on the improvement of maternal role adaptation [14,15].

In recent years, promoting mental health in non-clinical settings has become an urgent need, and mindfulness has been introduced as a good option to achieve it [16]. Mindfulness-based intervention (MBI) is also effective in increasing muscular relaxation, psychological adaptation, self-compassion, and quality of sleep [17,18]. The goal of mindfulness training is to maintain full attention to self-thoughts, feelings, and emotions. It also helps the individual to focus on the present moment and to assume a receptive and non-judgmental attitude [19]. Mindfulness-based cognitive therapy (MBCT) is a form of meditation rooted in Eastern religious rites. This method entails special behavioral and cognitive strategies which help the individual to focus on the attention process. It prevents the creation of negative moods, thoughts, and the tendency to have anxious responses, leading to the formation of pleasant feelings and emotions. This type of cognitive therapy includes a variety of meditations, stretching yoga, body scan, and cognitive therapy exercises [20].

It is widely accepted that adaptation to any new role, including the transition to parenthood, is often accompanied by stress, and this stress can bring about specific difficulties in adjusting to the new roles [11,21]. Previous studies have reported that MBI has beneficial effects in reducing anxiety, stress, and promoting psychological well-being in mothers during pregnancy, childbirth, postpartum, and the whole perinatal period in clinical settings [22]. In addition to promoting maternal mental health, mindfulness can enhance social and psychological development and regulate infant stress. However, few studies have focused on the use of MBI in promoting mental health in non-clinical settings [16]. The findings of two previous studies supported the positive effect of mindfulness on enhancement of self-confidence and self-esteem in breastfeeding mothers [23], improvement of mothers' mental health, and reduction of problems related to mother-infant interaction [24]. In another study, findings showed no difference between the results of using mindfulness as a preventive intervention in a non-clinical setting and a curative intervention in a clinical setting aimed at reducing parental stress or children's problems [16]. MBIs tailored to the perinatal period can be implemented in various ways, and length of the sessions and the duration of the exercises are shorter than those in other standard methods such as MBCT [25].

Given the several benefits of mindfulness in promoting mental health, the purpose of this study was to investigate the effect of MBI on maternal role adaptation and its domains among first-time mothers.