The significance of adverse childhood experiences (ACEs) on individuals' health has been widely acknowledged (Shonkoff et al., 2009). ACEs, including neglect, abuse, divorce or death of parents, among others, are potentially harmful events that may occur during an individual’s childhood (Almuneef et al., 2017; Lê-Scherban et al., 2018; Schickedanz et al., 2019). Research indicates that at least 50 % of American adults have suffered from ACEs before the age of 18 (Godoy et al., 2021). ACEs potentially increase the risk of chronic diseases in adulthood, with higher pitfalls of suffering from diabetes, hypertension, coronary heart disease, obesity, frequent headaches, and cardiovascular disease. Increased disease severity can in turn accelerate the hazard of premature death (Bremner, 2003; Anda et al., 2010; Almuneef et al., 2016; Sonu et al., 2019; Ittoop et al., 2020).

ACEs can adversely affect mental health and promote unhealthy behaviors. The degree of an individual’s adulthood depression can be augmented by an increase in reported ACEs (Anda et al., 2002). Compared to respondents without ACEs, those who reported even one ACE had significantly amplified probabilities of mental illness, depression, or anxiety. Those reporting four or more ACEs had an increased probability of mental illness of more than four times (Almuneef et al., 2016). ACEs have been implicated in unhealthy behaviors such as alcohol abuse (Anda et al., 2002; Rothman et al., 2008; Almuneef et al., 2014; Allem et al., 2015), and could remarkably boost health expenditures and the risk of debt (Schickedanz et al., 2019).

The life course theory states that an individual’s life course is developed by social context and personal interactions. Individuals are remarkably affected by life events involving others with whom they have certain social relationships (Elder, 1998). Life course perspectives share four key fundamental principles: long-term temporal patterns, the intersection of biography and history, linked lives, and human agency (George, 2007; Cooke, 2009). For the purposes of this study, we will focus on long-term temporal patterns and linked lives. Long-term temporal patterns accentuate the examination of temporality over extended periods of time, often covering decades or longer (Barker, 2003; Haas, 2008). Key assumptions of life course perspectives are that lives unfold over time in long-term pathways or trajectories, and that the present cannot be understood without knowledge of the past (George, 2007).

“Linked lives” indicates that individuals' life-course trajectories do not evolve on their own, but are configured by individuals' ties, relationships, obligations, and exchanges with important others such as partners and children. As dynamics of family relationships such as fertility vary with family members' life stages (Elder and Giele, 2009), maternal ACEs appeared in their teenage stage and this adversity can have long-term negative effects through intergeneration transmission. Given the features of long-term temporal patterns and linked lives, we consider that they can aid in our understanding of maternal ACEs and children's health.

In essence, the impact of maternal ACEs on children can be divided into two consecutive phases: “mothers' childhood to adulthood” phase of ACEs' transmission and “mothers' impact on their children” phase. When girls become mothers, progressive impact of ACEs will be unfolded. Long-term temporal patterns emphasize that maternal ACEs can engender disadvantages during adulthood in terms of socioeconomic status and physical health (De Silva and Sumarto, 2018; Schickedanz et al., 2019). While, linked lives further attest that mothers could deliver cumulative disadvantages to their children through interactions (Seabrook and Avison, 2019), thereby negatively impacting their offspring’s health and growth.

The relevance of ACEs to individuals' offspring has not been examined as much as the impact on individuals themselves. There has been concern that the negative impact could transmit intergenerationally, influencing the behavior, academic performance, health, and medical care of children whose parents suffered ACEs (Lê-Scherban et al., 2018; McDonald et al., 2019; Shah et al., 2020; Stargel and Easterbrooks, 2020). However, only a few studies have confirmed a substantial relationship between ACEs of parents and the health of their children (Dowd, 2019; Forke et al., 2019; Doi et al., 2020). Children whose parents suffered from ACEs had much higher probabilities of poor health and asthma (Lê-Scherban et al., 2018), as well as worse mental health in adulthood (Seteanu and Giosan, 2022). Children whose parents had childhood trauma were more likely to encounter trauma (Farina et al., 2020).

Life course studies concentrated on the biological and psychosocial responses of humans in health over time and explained the applicability of the phenomenon of becoming a mother (Black et al., 2009). Other scholars have utilized life course selection bias to examine the cumulative disadvantages of a father's absence in the life course (Sánchez, 2022). The concept of the life course has been embedded in a broader perspective on lifespan development (Alwin, 2012), with enlarging emphasis on intergenerational influences of “life events”.

Comparatively, little is known about the impact of maternal ACEs on their offspring’s health. Some scholars have considered both fathers' and mothers' ACEs (Dowd, 2019; Shah et al., 2020), while other scholars have been more inclined to center around maternal ACEs (Doi et al., 2020). Mothers play an important role in their offspring’s growth (Podesta, 2014), and so maternal ACEs were our focus in this study. Related research defined that maternal ACEs had a greater impact on their children's behavioral health than paternal ACEs (Schickedanz et al., 2018). ACEs of mothers increased their risk of depression in adulthood and reduced their level of mental health overall (Anda et al., 2002; Hughes et al., 2016), which would significantly affect their offspring’s health (Propper et al., 2007).

Additionally, it is unclear whether maternal ACEs have effects on the health of both daughters and sons. Increased vulnerability of female fetuses to maternal stress responses during pregnancy persists until adolescence (Quarini et al., 2016). It is a more vulnerable period for girls from late childhood to early adolescence during which they appear to be more susceptible to developing symptomology than for boys, particularly when exposed to maternal depression (Connelly and Connell, 2022). But some scholars held opposite views that children's gender did not have a moderating role in the relationship between maternal childhood abuse, mental health, and the offspring’s psychopathology (Miranda et al., 2013). These debates motivate us to examine the children's gender differences in the impact of maternal ACEs.

There are different perspectives about the influencing mechanisms of parental ACEs on children's health, with some explanations derived from biology and physiology. Several studies have considered that ACEs induced epigenetic changes and that DNA methylation (DNAm) subsequently connected parental ACEs with the health outcome of their offspring (Merrill et al., 2021). Other studies have argued that maternal ACEs can decrease women's ability to deal with stress during the perinatal period and increase their pain in pregnancy (Chung et al., 2009; Madigan et al., 2017; Racine et al., 2018). This could consequently disturb fetal and infant brain development and affect future childhood behavior and emotional maturity (Monk et al., 2019; Dachew et al., 2021).

Maternal education status, physical health, as well as mental health may even play more direct roles than biology in the relationship between the ACEs of mothers and the health of their offspring. ACEs produced worse mental health, lower physical health status, and disadvantaged economic and educational outcomes in adulthood (Almuneef et al., 2016; Bouvette-Turcot et al., 2017; Houtepen et al., 2020), which constituted structural forces accompanying adults to become parents. Lower maternal education levels facilitated inferior care for children (Egyir et al., 2016; De Silva and Sumarto, 2018), eventually deteriorating the children's health during adolescence (Choi et al., 2019). Equally, maternal unhealthy mental status enticed neglect for children, which provoked accidents, injuries, and medical delays that damaged children's health (Propper et al., 2007). However, it is unclear how maternal physical health, mental health, and education factors mediate the effect of maternal ACEs on the health of offspring. To this end, we tried to construct the theoretical framework for this research on the ground of the three aforementioned pathways.

Though little is known about the intergenerational transmission of maternal education status due to ACEs, previous studies have confirmed that ACEs could induce worse educational outcomes (Houtepen et al., 2020). ACEs have been correlated with lower education levels in adulthood (Jaffee et al., 2018; Westermair et al., 2018; Houtepen et al., 2020). Children, whose mothers have less educational training, have fewer resources available for them (McLanahan, 2004). Less-educated women have a higher risk of being single motherhood due to income inequality, which in turn could decrease intergenerational economic mobility (McLanahan and Percheski, 2008). Whereas a higher maternal education level results in better health for offspring (Medrano et al., 2008; Chen and Li, 2009). A higher education level benefits mothers with more health information, thereby promoting the health and growth of their children (Egyir et al., 2016; Miller et al., 2017; Karaoğlan and Saraçoğlu, 2018).

The more ACEs an individual suffers, the worse their health is likely to be in adulthood (Wade et al., 2016), including the higher risk of chronic diseases, obesity, and heart disease (Almuneef et al., 2016; Almuneef et al., 2017; Ittoop et al., 2020). Some researchers measured maternal health and healthy behaviors by using the parents' BMI index, whether the parents smoked, and whether the mother had seen the doctor in the past 12 months, and found that these factors had a significant correlation with their children's health (Case and Paxson, 2002). Poor self-rated health (SRH) of mothers was also significantly correlated with the worsened health of their children (Propper et al., 2007). Hence, we prefer to verify whether mothers who had ACE exposure may propagate negative consequences on the physical health of their children.

Existing studies have predominantly focused on developed countries. Thus, empirical studies from developing countries are imperative, especially the rapidly transitioning nations such as China. On the one hand, the severity of ACEs in China may be beyond our anticipation. 66 %–88 % of the population underwent at least one ACE (Ho et al., 2018; Chang et al., 2019; Zhang et al., 2020; Yu et al., 2021). The prevalence of ACEs in China has its particular historical background including profound socio-economic reform, typical events (such as the Great Famine), and the rapid industrialization over the past few decades (Chen and Zhou, 2007; Wang and Wang, 2021; Xie and Zhu, 2022). China has made great strides in modernization and marketization, which further diminished family stability and massive social problems have appeared in the wake of the increasing number of single-parent households (Peng and Hu, 2015). On the other hand, Chinese parent-child interaction was correspondingly closer. Parents were highly involved in their children's lives and learning from infancy to adulthood (Hofstede, 1980). Intimate interactions and dependencies also allowed parents to have a greater impact on their children (Hofstede, 1980; Chao, 1994; Yuan et al., 2016).

At present, research on ACEs in China mainly focused on individual mental health (Chen et al., 2022; Jiang and Jiang, 2022), subjective well-being (Fu and Chen, 2022), entrepreneurial behaviors (Zhao and Li, 2022), and happiness (Huang et al., 2021). Population in the research mainly includes older adults (Fu and Chen, 2022), adolescents (Chen et al., 2022), adults (Zhao and Li, 2022), and college students (Huang et al., 2021). Wang et al. (2022) investigated associations of maternal ACEs with behavioral problems in preschool children. Generally, research on the intergenerational impact of ACEs in China is still scant.

In sum, we insist that to move forward with the intergenerational perspective of life course theory, there must be empirical testing of key postulates to determine which parts of the theory are supported. In general, some concerns must be clarified. Do maternal ACEs affect children's health? How do maternal ACEs influence children's health, and by what mediating mechanisms if the association was testified? To respond to these academic gaps and based on the previous literature review, we will empirically testify whether maternal ACEs negatively affect children's health (Hypothesis 1); whether maternal education level, maternal physical health status, and maternal mental health mediate the relationship between maternal ACEs and children's health (Hypothesis 2–4).

In line with this, we utilized relevant data from China and attempted to make contributions by exploring the relationship between ACEs of mothers and the health of their children, investigating the effect of maternal ACEs on daughters and sons, and clarifying the influence of maternal ACEs on children's health through the mediating variables of maternal education level, physical health, and mental health. Considering the large number of people harmed by ACEs, and the social obligation to curb the intergenerational transmission of hardship, we aim to provide insights for targeted policy intervention that might improve the outlook for future generations.