Paternity leave: A systematic review of studies in education and psychology from 1990-2019

Paternity leave is integral to transition to parenting and father-children bonding, providing fathers the necessary time to take part in an equal share of household labour. Still, policy legislation on paternity leave from work for fathers is not prevalent; therefore, there exists no comprehensive review of their potential impacts and benefits to guide educational and psychological research in this area. This systematic review aims to acknowledge the extent to which different paternal leave for fathers is studied, focusing on the shifts in the trends of the inquiry of the fathers' leave based on time, study location, research context, and sampling by addressing this gap. Methods A systemic review of peer-reviewed literature retrieved from electronic databases was conducted. A total of 1993 abstracts were included for the study and selected 141 published papers from 1990 to 2019 on the use of paternal leave were reviewed. The main findings were coded and analysed through NVIVO 12. Results The synthesis of the results suggested that there has been growing interest in paid parental leave regarding fathers in particular over time. The findings showed that the focus was on the effects of paternity leave on the transition to parenting and gender equality.


Introduction
Parental leave policies are defined as the legislation for parents that permit employees to take time off work for pregnancy, birth, and adoption, personal illness, or care for family members, including children, parents, and spouses (Nandi, et al., 2018, p. 435). By 2013, all Organization for Economic Co-operation and Development (OECD) countries other than the United States offered some form of national paid leave policy for parents. For example, the range of parental leave is between 14 and 17 weeks, with pay at 100% in developed countries such as Greece, Israel, the Netherlands, New Zealand, Spain, and Switzerland (OECD, 2016). In other countries, policymakers have also worked to increase women's labour force participation by facilitating work-life balance through childcare and parental leave policies (Burgess, Gregg, Propper, & Washbrook, 2008, p. 169). However, those policies are still inadequate at satisfying the needs of fathers to involve in caregiving and household labour (Ruppander, 2010, p. 965); as a result, creating gender inequalities (Kotsadam & Finseraas, 2011, p. 1611. Even though a shift in fathers' roles in children's lives can be observed in many cultures (O'Brien, Berit, & Elin, 2007, p. 377) and men are not seen as solely breadwinners but responsible for sharing care with their partners; mothers are still acknowledged as the primary caregivers (Huerta, et al., 2014, p. 2). This might explain the reasons for unsatisfying policy arrangements for fathers. However, due to the influences of these changes in gender roles in marriage in modern societies, research focus has shifted to the gendered division of household tasks and involvement of men in family life (Almqvist & Duvander, 2014;Schober & Zoch, 2018). Parenting roles that fathers recently were taken, and the responsibilities of employment also compel men to find a new balance in their lives (Johansson, 2011).
Many studies claim that family-friendly policies, particularly paternity leave-taking, is positively associated with father involvement in housework and care activities (e.g., Hosking, Whitehouse, & Baxter, 2010;Tanaka & Waldfogel, 2007). By having more time to spend at home, fathers also fulfil an active role in caring for the infants, helping them develop better bonds with their children (Almqvist & Duvander, 2014;. According to Rostgaard (2002, p. 344), by offering gender equality, paternal leave policies can encourage better relationships between children and fathers; therefore, advancing children's well-being outcomes. Furthermore, father leave policies can help mothers to return to their job and lead them to participate in the labour market; as a result of that, gender inequalities in labour force participation might be lessened (Nandi et al., 2018;Dearing, 2016). Based on Bratberg and Naz's (2014, p. 508) findings, there is also a relationship between fathers' use of paternity leave and the reduced use of mothers' sickness absence, leading to a change in the employers' notions about hiring women. On the other hand, job-protected paid leave policies can allow parents to contribute to household income and savings that may reduce the financial burden after a new-born comes to the family (Nandi et al., 2018, p. 436).
Positive father involvement brings great advantages to children (O'Brien, 2009;Romero-Baisas, 2015), to men as fathers (Smith, 2011), to the whole family (Cools, 2015;Rehel, 2014) and the society (Dermott, 2001). Despite the importance and growing attention to fathers' use of paternity leave, parental leave is such a rare case for many countries, and there is still significant variation in allowances and benefits and outcomes in different settings (Kaufman, 2017, p. 2). For instance; according to the latest OECD policy brief report (2016), only 12 OECD countries (i.e., Korea, Japan, France, Luxembourg, Portugal, Belgium, Iceland, Sweden, Norway, Finland, Germany, and Austria) offer at least two months of paid paternity leave that can only be taken by the father. Meanwhile, the UK, Australia, Denmark, Estonia, Poland, Slovenia, and Spain limit father-specific leave to two weeks (OECD, 2016). As seen from this variation and examples, the importance of paternal leave is not well understood by the authorities, and a considerable proportion of fathers still face obstacles and economic or social consequences for taking leave (Ray, Gornick, & Schmitt, 2010, p. 197).
As indicated above, there is an upward trend about the inclusion of fathers to the parenting process through remediation of paternity policies; however, research on father involvement in parenting during pregnancy and after childbirth is insufficient. Contrary to European countries, developing countries such as Turkey have limited national paternity leave policy giving fathers the right to take paid time off work following a child's birth (Kurucirak & Kulakac, 2014). Moreover, there is a lack of information and awareness on this issue within their contexts. As of our knowledge, this is one of the first studies on the fathers' parental leave comparing a range of countries involving developed, developing, and underdeveloped countries. Previous systematic review studies have mainly concentrated on the effects of paternity or parental leave on health outcomes, and none of them looked at fathers' leave from the point of psychology and education. Therefore, this review can lead us to understand what researchers in these areas mainly work on and the gaps in the literature to see what needs to be studied in the future. Thus, for this review, we summarise the evidence on the trends and focus of papers related to paternity leave delivered in different countries. Additionally, we examined the effects of paternity leave policies in various settings. Therefore, this systematic review aims to evaluate the empirical literature concerning the impacts of paternity leave and show the evidence for the necessity of fathers' leave.

Methods
Various methods have been utilised to capture paternity leave for fathers in various contexts to assess subjects related to father-child bonding, gender equality, the transition to fathering, the social and economic outcomes, and its relation to health issues. These different studies employ a wide range of methods in a variety of contexts and researching various topics in the fields of education and psychology; however, there are limited review studies to our knowledge that analyse the place of paternity leave in the world (e.g., Andres, Baird, Bingenheimer, & Markus, 2016;Humphries et al., 2017;Nandi et al., 2018) and none of them looks for the nature of the papers in these disciplines. In this regard, we rely on that a more comprehensive review of existing studies on paternity leave in psychology and education can be conducted based on the specific titles, keywords, and abstracts. Accordingly, this review aims to carry out a thorough review of paternity leave to understand the shifts of studies on paternal leave policies over time, research context, sampling, and research settings that selected papers are placed through utilising a systematic review.
We began with analysis to form a frame for research on paternity leave policies by looking for the figures and trends based on time and study locations. In the following step, we analysed the selected papers in detail to present an understanding related to the methodology used in the articles, sample characteristics, and subject area. As our focus was to put paternity leave into a frame of the shift in existing literature over time regarding studies in psychology and education, we conducted this review to retrieve literature published in English using the databases ProQuest, PsycInfo, Web of Science, Science Direct, Medline, ERIC, British Education Index, and Education Research Complete from 1990 to 2019. Multiple search terms involved "paternity leave," parental leave," "paternal leave," "fathers leave," "family leave," and "paid leave" integrated with terms narrowing the searches to papers acknowledging the effect of these policies on paternal leave.
The inclusion criteria for the studies were to be published in peer-review journals and reported and evaluated the relationship between parental leave and father involvement. As we focused on specifically paternity leave for fathers and how it is approached in education and psychology, we did not analyse articles related to other fields such as those with medical outcomes. We also employed several criteria for exclusion. Initially, we excluded articles related to sickness-related absences from work, medical leave policies, maternity/maternal leave, and family illness, which did not take place in the scope of paternity leave. Then, we excluded theses/dissertations and nonpeer-reviewed or grey literature. 1993 articles were identified for a research title/abstract review on the final articles after removing duplicates, which, then, was followed by a full-text review to make the final decision for included articles (Figure 1). Those articles for the title/abstract review were assigned randomly to 2 reviewers for reliability purposes and decided papers for full-text review. Then, we reviewed full-text articles to clarify the title-abstract review and shared our arguments before concluding for inclusion and exclusion for the article. All eligible studies were classified into five groups: Years, countries, methodology, sampling, and subject area. They were then separated into subcategories through the NVIVO 12 program based on the similarities and differences of the codes extracted from the data. We divided the 'years' section into seven subgroups to draw a picture of variations of the number of papers in 5years periods: 1990-1994, 1995-1999, 2000-2004, 2005-2009, 2010-2014, and 2015-2019. 'Methodology' codes were classified as quantitative, qualitative, mixed methods, and review. When we finished analyzing the selected articles, we also gathered data sampling information in the chosen articles together, which then created groups as fathers, both parents, both parents and children, children, and others. Similarly, we finalised subject areas of the papers as the transition to parenting, gender equality, policy, financial issues, childcare, and others (reasons, the impact of education, religion, law, and employment).

Findings
The findings of the study were presented in two sub-sections. We begin with the bibliometric analysis of articles included in this review to form a frame for paternity leave, focusing on the shifts over time and study locations. The systematic review results were then discussed with particular attention given to sample characteristics who participated in the relevant studies or the focus of the research on these samples, subject areas, and methodology approached in those articles with a comprehensive understanding.

Bibliometric results
Bibliometrics, as a method for quantitative analysis, is applied to evaluate research performance, particularly journal articles (Cobo, Martinez, Gutierrez-Salcedo, Fujita, & Herrera-Viedma, 2015). Hence, in this study, to produce a general overview of the phenomenon and acquire a better picture of the shifts in paternity leave research, the articles published in paternity or parental leave between 1990 and 2019 were included a bibliometric analysis. This would further lead to interpret how fathers' leave has been affected by the changes in laws, policies, and sociocultural positions in different cultures. psychology and education, especially over the last decade. When we look at Figure 2, which shows the number of articles produced in years, it can be noted that the interest in fathers' leave began to increase from 2006. This rise might be related to the emergence of parental leave in many countries happening much later than maternity leave, which was merely for women workers. For instance, the European Union recognised parental leave -for both parents -by 1996, despite the UK's opposition (Kamerman & Moss, 2009, p. 2). Besides, this rise might be explained with the enhancement of the legislation. Australia can be seen as an illustration of this legislation developed in 2005 with the Family Provisions Test Case, which provides employees with a variety of 'new' rights such as shifting 52 weeks of unpaid leave to 2 years and the implementation of 8 weeks parental leave for both mothers and fathers to use simultaneously (Brennan, 2009, p. 21). Thus, it was essential to look at the countries in these papers published individually to comprehend the varied number of articles. Study locations were disclosed through the coding of all settings in selected articles related to parental or paternity leave. Looking at Figure 3, it is apparent that paternity leave gains importance worldwide, ranging from more developed countries such as Sweden and the US A to developing countries such as Nigeria. Researchers' interest might be more visible in countries where policy supports fathers' leave and protect their jobs when they are on leave since fathers tend to use paternity and parental leave more when they are well-paid (O'Brien & Moss, 2010). It can be regarded from the analysis that a substantial number of papers originated from the United States, Sweden, and the UK, followed by Norway and Canada. Although these results represent an emerging trend in paternity leave, papers examined for this review show the researchers' attention on this topic, particularly comparing different arrangements for fathers and parents in different countries to suggest a beneficial policy for both parents and children. Among those countries, Sweden was the first to allow fathers to take paid paternity leave in 1974, which directly impacted issues such as gender equality, facilitating transmission to parenting and childcare (Mansdotter, Fredlund, Hallqvist, & Magnusson, 2010). In contrast, the United States is one of the few countries throughout the world in which even mothers are ineligible for paid leave after childbirth (Zagorsky, 2017). However, it is essential to show that even in leading countries for applying paternal leave policies, more research on this topic needs to be undertaken to assess the outcomes of those policies.  Table 1 provides the results obtained from a more detailed analysis of articles selected for this review by illustrating the time period of different categories of methodology, sample characteristics, and subject area. What stands out in the table is that there is only a minor difference in using the methods in researching paternity leave except for mixed-methods. However, the scope of the article was the investigation of the trends related to fathers' leave in the fields of education and psychology; therefore, illustrating a limited research area does not reflect a preference for one specific method. As the following step, after the completion of the analysis based on the trends in used methodology, we looked for sample characteristics in related papers. These sample characteristics were either those who participated in the studies or whom the review papers depended on (the intended audience). However, in some policy papers, there were no specific groups referenced; indeed, in some studies, the intended audience was broad such as politicians, fathers, parents, lawyers, and they discussed paternal leave in general without any particular references. Therefore, we put these research sampling into the closest one in the sample characteristics group or the 'others' categorisation. For instance, if the article discusses paternity leave from the point of lawyers, we reviewed the whole paper to look for whether it relies on fathers or both parents: paternity leave or parental leave. Based on this analysis of sample characteristics, it is revealed that the papers primarily were based on fathers' perceptions, their experiences, and how they interpret the period to become a father as expected. This trend gradually increased over time, beginning in earlier research in the 1990s till 2019. It is followed by the studies related to both parents -mothers and fathers-and a few studies were interested in children's experiences and others such as academics, students, or managers. Perhaps, the most interesting aspect of this is that although we selected papers from educational and psychological journals and studies, almost 3% of studies looked for the relationship between paternity leave and its effects on children. This is an unexpected result meaning that there needs to be more research on this subject.

Systematic review results
In the final part of the systematic analysis of selected papers, we looked for the aims of the studies and identified subject areas. We concluded with six categories under this theme and a separate class named 'others' to identify those that did not fit into any groups. The first and most studied category was revealed as 'transition to parenting,' related to the papers based on fatherchildren relationships and fathers' transition to becoming a parent. The proportion of the articles falling into this category gradually increased by this time. Gender equality, as the second subject area, was mostly based on the perception of fathers' and mothers' roles in the household and childcare along with fathers' bonding with their children. Table 1 above shows that the interest in the relationship between paternal leave and gender equality gradually increased, similar to the transition to parenting. Policy reviews and articles related to the policy area were categorised as the third group, and policy research increased until 2014; a small decrease can be seen in Table 1 after this date. The relationship between paternal leave and financial factors, childcare, law, and others did not get attention as much as the first three categories in education and psychology.

Discussion and conclusion
Based on our findings, the majority of papers on paternity leave were published in the U.S.A., Sweden, and the UK, followed by Norway and Canada. According to , fathers in the US A do not have a right to paid paternity leave assured by the laws. However, a large proportion of studies were conducted in the US A when compared with others. Although there might be several factors increasing fathers' involvement in housework and childcare activities such as extended women labour force, developing diversity in family, and shifts in attitudes towards employment and care activities (Huerta, et al., 2014), the substantial amount of research can be explained by the necessity of family-friendly leave policies for fathers in the USA. Considering economic conditions in the USA, which can be seen as advanced and their place as one of the most developed countries in the world (Shin, 2020), the reason for discussing the country's insufficient policies to meet parents' needs and to provide basic rights of workers who have a child or children becomes clear. Yet, there needs to be more studies in this field in order to lead the policymakers to act. On the other hand, there is a positive attitude in OECD countries where father-friendly arrangements for work and care have long been presented, beginning with Sweden (OECD, 2019).
According to Tanaka and Waldfogel (2007), family-friendly policies allow both parents to clear obstructions and maximise their parent-children bonding opportunities. Further arrangements for specifically fathers' leave are developed, which enables them to present around childbirth, observe their children's growing up and support them at this time, share responsibilities with mothers, and support women in housework (Rehel, 2014, p. 112). Our findings support these arguments by presenting the transition to parenting and gender equality as the most-researched subject areas in selected papers. The importance put on the transition to parenting shows a particular interest in the relationship between paternity leave and its strong connection to fatherhood, followed by 'gender equality.' Based on their study with 100 Australian fathers, Brady et al. (2017, p. 69) found that for fathers, spending the first six to eight months with their new-born child could boost their early paternal bonding. Also, Haas and Hwang (2008) conducted a study with fathers from large companies in Sweden. They found out that paternity leave enhances fathers' participation in childcare and their fulfilment with their relationship with children.
Fathers might still face some challenges they need to address once they use paternity leave (Doucet, 2009). To illustrate, being a father for the first time is a unique experience for fathers, and they may not know how to manage this new role (Reimer, 2017). Yet, mothers may have some expectations from the fathers such as sharing chores, responsibilities of new-born, and caring duties (Miller, 2013). In this case, parental leave policies influence parental behaviours for especially fathers who need to be more receptive to internalise parenting roles such as sharing duties with their partners in the house and child-related issues. Therefore, effective paternity leave policies lead to a natural consequence: promoting gender equality.
Finally, particularly, mothers' paid leave is supported in many countries (Kamerman S. B., 2005), except in the USA (Zagorsky, 2017); however, there is no specific regulations or a limited one for fathers' parental leave in many countries such as South Africa (Smit, 2011), Canada (Ball & Daly, 2012), Japan (Nakazato, 2017), Israel (OECD, 2019) and Switzerland (Valarino & Gauthier, 2016). For example, while in Europe, the average of paternal leave is about two weeks, in the Slovak Republic, there is no such right for parents (Gerbery, 2018). There was a lack of evidence about the role of the policies, and it is noticeable that all countries have their own policies (Karu & Tremblay, 2017). Though this variation is argumentative, it is essential to consider the countries' culture, economic development, and social structure. It should be acknowledged that there are countries where women still face challenges with finding a place in working life (Sidani & Al Hakim, 2012), and their main role is to take care of the household (Nicolete & Almeida, 2018). Besides those developing countries, our study demonstrates that there are several studies related to the importance of parental leave as encouraging gender equality and fatherchildren relationship in a number of developed countries. However, only a few of these countries applied paid paternal leave policies for fathers. These results show us that paternal leave for fathers still needs to be developed. Furthermore, the role of fathers in childcare needs to be emphasised. As pointed out in previous studies, the fathers' role is important to early childhood (Lynch, 2019). However, there is a lack of studies on child education and their development, which can provide evidence to support the role of fathers leave on children's later academic lives.

Limitations
The findings discussed in this paper offered considerable insights about fathers' right to paternal leave and the development of research related to this area. We attended to frame a big picture of global studies. However, there are a few limitations that are common in systematic reviews. A great effort was made to ensure that mistakes were minimised, such as inaccurate classification of data or missing materials; from the beginning of the research as identifying keywords to search in databases and limiting databases to several ones; to the final part of discussing the findings. Yet, several factors should be considered for future research. Although the current study included search terms on father, paternity, and paternal leave, our findings claimed that mostly research combining fathers' leave with gender equality, transmission to parenting, and family policies. It was noticeable that there is a significant gap in the relationship between the influence of fathers' leave on whole family interaction, specifically children's social, emotional, psychological, and educational development. To obtain a clear picture of the relationship between fathers' leave and children's development, it might be beneficial to conduct more longitudinal studies. Additionally, relevant confounders (e.g., the number of siblings, the child's position in the family, and caregivers) should also be included to further elucidate this complicated relationship.
Supplementary Materials: The following are available online at https://osf.io/hwfuz/