The phenomenon of declining fertility rates has emerged as a major demographic challenge across the globe, particularly in developing nations such as Iran [1, 2]. Over the past few decades, many countries have witnessed a substantial decline in birth rates, leading to concerns about population aging, workforce shortages, and potential economic stagnation [3]. In Iran, the total fertility rate (TFR) has dropped from approximately 6.5 children per woman in the early 1980s to around 1.8 in recent years [4]. This dramatic decline raises critical questions about the underlying factors influencing couples' decisions to have children and the implications for future population dynamics [1, 2]. Several factors contribute to the decline in fertility rates, including increased access to education and employment opportunities for women, urbanization, and changing societal norms regarding family size and child-rearing [5, 6]. As women gain higher education and participate more actively in the workforce, their priorities often shift towards career development and personal fulfillment, which can lead to delayed marriage and childbearing [7]. Additionally, urbanization tends to correlate with smaller family sizes, as urban living often entails higher living costs and limited living space, prompting couples to reconsider their childbearing intentions [8, 9]. The transition from traditional to modern lifestyles has also played a crucial role in shaping reproductive behavior [10]. In many societies, the traditional family model, characterized by larger family sizes and early childbearing, is being replaced by a model that values smaller families and delayed parenthood [8, 11, 12]. This shift is often accompanied by changing gender roles, where women increasingly prioritize their careers and personal aspirations over early marriage and childbearing [13]. As a result, many couples are opting to have fewer children or delaying childbearing until they feel more financially secure and established in their careers [10, 11].

Understanding the factors that influence childbearing intentions is crucial for policymakers and social planners [14, 15]. Fertility intentions are shaped by a complex interplay of individual, social, cultural, economic, and governmental factors [15, 16]. Identifying these determinants can help develop targeted interventions and policies that address the barriers to childbearing, thereby promoting family growth and stability [10, 17, 18]. Moreover, understanding these factors can aid in predicting future demographic trends, which is vital for planning healthcare, education, and social services [19, 20]. Individual factors such as age, education level, and socio-economic status significantly impact fertility intentions. Younger couples with higher educational attainment often express a greater desire for children, while those with lower educational levels may have different priorities or face economic constraints that influence their decisions [21, 22]. Demographic factors, including marital status and family structure, also play a significant role [15, 23]. Couples who are married and have supportive family networks are generally more inclined to have children than those who are single or lack familial support [18, 24].

Cultural norms and values are critical in shaping childbearing intentions [25]. In many societies, traditional beliefs regarding family size and the role of children influence couples' decisions to have children [18, 26, 27]. For instance, in cultures that emphasize the importance of large families, couples may feel societal pressure to conform to these expectations [19, 28, 29]. Conversely, exposure to modernity and globalization can lead to shifts in attitudes towards smaller family sizes, particularly among younger generations [30]. Social factors, including peer influences and community support, also significantly affect childbearing intentions [19, 31]. Couples who perceive strong social support from family and friends are more likely to express a desire for children, highlighting the importance of community in fertility decisions [18, 24, 32].

Economic stability is another crucial determinant of childbearing intentions. High costs associated with raising children, coupled with financial insecurity, often lead couples to postpone or forgo having children altogether [33-35]. Economic policies that provide financial support for families can positively influence fertility intentions, as they alleviate some of the financial burdens associated with child-rearing [36-38].

Health-related factors, such as access to healthcare and perceived health risks associated with pregnancy, can also influence childbearing intentions [39-42]. Couples who have concerns about their health or the health of their potential children may delay or avoid having children [11, 43, 44]. Furthermore, governmental policies aimed at encouraging childbearing, such as parental leave and financial incentives, have shown mixed effectiveness. Some policies have successfully promoted higher fertility rates, while others have not adequately addressed the underlying concerns of couples [45-48]. Recent evidence also highlights that educational and counselling-based interventions can positively influence reproductive attitudes and decision-making. For example, information-based counselling has been shown to enhance individuals' knowledge, perception, and motivation regarding childbearing [49]. This underscores the importance of understanding individual, demographic, cultural, social, economic, and governmental determinants for developing effective policies and interventions that can support couples in their childbearing decisions [9,50-53]. Despite extensive systematic and scoping reviews examining determinants of fertility intentions in specific populations, there remains a lack of comprehensive evidence that integrates these multifactorial influences within the global context of fertility decline. This review aims to fill this gap by synthesizing existing literature on factors affecting childbearing intentions across diverse contexts. It provides a comprehensive overview of how demographic, economic, social, and cultural elements shape reproductive choices and inform policies that support couples' childbearing intentions amid global fertility decline. Accordingly, this review aims to answer the following research questions: what key factors influence childbearing intentions worldwide, how do these determinants shape reproductive decisions, and what implications do these findings have for the development of effective policies and interventions to address declining fertility rates?

To provide a better illustration of the interconnections among diverse factors influencing fertility intentions, the findings were categorized according to their level of influence: micro (individual and personal), meso (community and social), and macro (economic and policy-related) factors. Each theme is discussed in detail below.

The findings of this review showed that childbearing intentions are influenced by a complex interaction of demographic, economic, social, and personal factors. Demographic determinants such as age, marital status, and cultural preferences emerged as central themes. The findings indicate that women who delay childbearing to pursue education or career goals often show lower fertility intentions. Economic stability is another major factor, as couples facing financial insecurity are less inclined toward larger families. Social factors, including the availability of family and community support, substantially influenced childbearing decisions. Finally, personal motivations such as emotional fulfillment and life satisfaction were found to encourage couples toward parenthood. The identified determinants align closely with the policy strategies implemented in various countries that could serve as models. For instance, Sweden’s comprehensive family policy, which provides extended parental leave (allowing parents to share 480 days of paid parental leave, which can be used until the child is 12 years old), subsidized childcare, and flexible work arrangements, directly addresses the social and family support barriers revealed in this review by enabling both parents to share child-rearing responsibilities, consequently influencing couples’ willingness to have more children [57]. Similarly, France’s financial support and childcare policies have focused on removing financial barriers to childbirth through direct monthly family allowances, tax incentives, and a robust childcare system to reduce the financial pressures associated with raising children, aligning with this review’s evidence that economic insecurity discourages parenthood [73]. In Japan, the government has recently taken steps to address declining birth rates through the ‘Angel Plan’ and ‘New Angel Plan,’ which emphasize work-life balance and child-rearing support, and respond to the cultural and social dimensions identified in this review. The measures include increasing childcare facilities and promoting paternal involvement in childcare, aiming to shift cultural norms regarding gender roles [74]. While these successful programs have emerged in high-income contexts, their underlying principles provide valuable insights for developing countries like Iran, where fertility has declined in recent decades. Iran's strong family-oriented culture offers a foundation for social and intergenerational support similar to Sweden’s emphasis on shared caregiving. However, economic constraints and limited childcare infrastructure highlight the need for strategies closer to the French model, focusing on financial stability and affordable childcare services. Moreover, promoting gender equality in family roles and encouraging flexible work arrangements would benefit from adopting aspects of Japan's approach. Given the ineffectiveness of some current governmental policies, a comprehensive review and amendment of these strategies is essential. Policymakers should focus on addressing the most significant barriers to childbearing, such as economic insecurity and lack of social support, while also promoting positive cultural attitudes towards family growth [75-77]. Successful policies, a solid foundation, should be tailored to the specific needs and cultural contexts of different societies. For instance, in countries where traditional family values are strong, policies that emphasize the importance of large families and provide support for multiple children may be more effective [57, 74]. In contrast, in societies with more individualistic values, policies that focus on work-life balance and gender equality may be more appropriate [78-80]. It is also crucial for governments to collaborate with healthcare providers, educational institutions, and community organizations to ensure a comprehensive and coordinated approach to promoting childbearing intentions. Healthcare providers can offer pre-conception counseling and support services to help couples plan for pregnancy, while educational institutions can incorporate family planning and parenting education into their curricula [1, 64, 81, 82].

This scoping review synthesized existing evidence on the multifaceted factors influencing childbearing intentions and provided an integrated understanding of how demographic, economic, social, and personal determinants interact to shape fertility behavior. The review contributes to the field by offering a comprehensive framework that connects micro-, meso-, and macro-level influences. The findings underscore that financial security and robust social support systems are the most decisive drivers of fertility intentions. Policymakers should therefore prioritize strategies that enhance economic stability through family financial incentives and expand accessible childcare and parental support programs. These measures can foster an environment in which couples feel both capable and supported in their decision to have children. Future research should move beyond descriptive analyses toward mixed-methods designs to explore both statistical patterns and the underlying motivations, beliefs, and cultural norms that shape reproductive choices. These approaches can help uncover the “why” and “how” behind fertility-related behaviors, offering deeper insight into the socio-cultural dynamics that influence childbearing in diverse contexts.