Building a family at advanced parental age: a systematic review on the risks and opportunities for parents and their offspring.

Study question: What is the existing empirical literature on the psychosocial health and wellbeing of the parents and offspring born at an advanced parental age (APA), defined as 40 years onwards?

Summary answer: Although the studies show discrepancies in defining who is an APA parent and an imbalance in the empirical evidence for offspring, mothers, and fathers, there is a drive towards finding psychotic disorders and (neuro-)developmental disorders among the offspring; overall, the observed advantages and disadvantages are difficult to compare.

What is known already: In many societies, children are born to parents at advanced ages and there is rising attention in the literature towards the consequences of this trend.

Study design size duration: The systematic search was conducted in six electronic databases (PubMed including Medline, Embase, Scopus, PsycInfo, CINAHL, and SocINDEX) and was limited to papers published between 2000 and 2021 and to English-language articles. Search terms used across all six electronic databases were: ('advanced parental age' OR 'advanced maternal age' OR 'advanced paternal age' OR 'advanced reproductive age' OR 'late parent*' OR 'late motherhood' OR 'late fatherhood') AND ('IVF' OR 'in vitro fertilization' OR 'in-vitro-fertilization' OR 'fertilization in vitro' OR 'ICSI' OR 'intracytoplasmic sperm injection' OR 'reproductive techn*' OR 'assisted reproductive technolog*' OR 'assisted reproduction' OR 'assisted conception' OR 'reproduction' OR 'conception' OR 'birth*' OR 'pregnan*') AND ('wellbeing' OR 'well-being' OR 'psycho-social' OR 'social' OR 'ethical' OR 'right to reproduce' OR 'justice' OR 'family functioning' OR 'parental competenc*' OR 'ageism' OR 'reproductive autonomy' OR 'outcome' OR 'risk*' OR 'benefit*').

Participants/materials setting methods: The included papers were empirical studies in English published between 2000 and 2021, where the study either examined the wellbeing and psychosocial health of parents and/or their children, or focused on parental competences of APA parents or on the functioning of families with APA parents. A quality assessment of the identified studies was performed with the QATSDD tool. Additionally, 20% of studies were double-checked at the data extraction and quality assessment stage to avoid bias. The variables sought were: the geographical location, the year of publication, the methodological approach, the definitions of APA used, what study group was at the centre of the research, what research topic was studied, and what advantages and disadvantages of APA were found.

Main results and the role of chance: A total number of 5403 articles were identified, leading to 2543 articles being included for title and abstract screening after removal of duplicates. This resulted in 98 articles included for a full-text reading by four researchers. Ultimately, 69 studies were included in the final sample. The key results concerned four aspects relevant to the research goals. (i) The studies showed discrepancies in defining who is an APA parent. (ii) There was an imbalance in the empirical evidence produced for different participant groups (mothers, fathers, and offspring), with offspring being the most studied study subjects. (iii) The research topics studied underlined the increased risks of neuro-developmental and psychotic disorders among offspring. (iv) The observed advantages and disadvantages were varied and could not be compared, especially for the offspring of APA parents.

Limitations reasons for caution: Only English-language studies, published between 2000 and 2021, found in the above-mentioned databases were considered for this review.

Wider implications of the findings: More research is necessary to understand the risks and benefits of building a family at an APA for the offspring when they reach adulthood. Furthermore, studies that explore the perspective of older fathers and older parents from non-Western societies would be highly informative.

Study funding/competing interests: The writing of this manuscript was permitted by financial support provided by the Swiss National Science Foundation (Weave/Lead Agency funding program, grant number 10001AL_197415/1, project title 'Family Building at Advanced Parental Age: An Interdisciplinary Approach'). The funder had no role in the drafting of this manuscript and the views expressed therein are those of the authors. The authors have no conflicts of interest.

Registration number: This systematic review is registered in Prospero: CRD42022304564.