Background
Infertility is defined by the World Health Organization as “the failure to achieve a clinical pregnancy after 12 months or more of regular unprotected sexual intercourse” [
1]. It is a public health problem affecting 9% of reproductive-aged couples throughout the world [
2]. A growing body of research suggests that both infertility and its treatment represent a negative psychological burden to affected couples and this can has a considerable impact on their quality of life (QoL), life satisfaction and well-being [
3,
4]. One of the most often-cited repercussions of infertility is depressive disorder, and increasing evidence indicates that this disorder is associated with poor QoL in people with infertility [
5‐
7].
Many of the phenomena studied by researchers in social and behavioral science are dyadic in nature (e.g., research on male-female dyads and parent-child dyads). The observations arising from such designs are not independent, but interdependent; however, in this case independence refers to independence from dyad to dyad [
8,
9]. Statistically, conventional parametric statistics developed for independent observations are not appropriate for non-independent observations. Instead, the non-independence due to the dyadic nature of data must be taken into account when relationships are investigated. One situation, in which “non-independence” is relevant, is that a characteristic or behavior of one person affects his or her partner’s outcomes; therefore, a model that takes non-independence into account is needed for an accurate analysis [
9]. The Actor–Partner Independence Model (APIM), an innovative dyadic analysis approach, simultaneously estimates the effects of one’s own characteristics and one’s partner’s characteristics on an outcome variable [
9]. The APIM approach uses the dyad, and not the individual, as the sampling unit and provides separate but simultaneous estimates of actor and partner effects [
9]. The actor effect assesses the degree to which one’s outcome is influenced by one’s own characteristics, whereas the partner effect assesses the degree to which a person’s outcome is influenced by characteristics of the partner.
Most studies evaluating the relationships between depression and QoL in infertile couples use the individual as the unit of analysis [
10,
11]. Although valuable, these studies provide no information on the impact that partner depression has on individual QoL. In addition, since infertility is a shared couple problem, examining the impact of partner depression is especially relevant [
12]. In other words, the male’s/female’s depression does not only influence his/her own QoL, but also his/her partner’s QoL. Thus, the current study aimed to: (a) evaluate whether there were differences in the levels of depression and QoL between male and female dyads experiencing infertility; (b) use the APIM approach to elucidate and differentiate actor effects and partner effects of depression on QoL. In this study, we examine the following research hypotheses: (1) There is a significant difference between males and females’ depression; (2) There is a significant difference between males and females’ QoL; (3) One’s level of depression is associated with his/her own level of QoL (actor effects); (4) One’s level of depression is associated with his/her spouse’s level of QoL (partner effects); (5) There is a significant difference between male and female actor effects of depression on QoL; (6) There is a significant difference between male and female partner effects of depression on QoL; (7) There is a significant difference between actor effect and partner effect separately for both males and females.
Discussion
To the best of our knowledge, this is the first study to apply the APIM approach to evaluate the impact of actor and partner depression on QoL in couples experiencing infertility. Although the majority of studies examining psychological distress and QoL both in infertile and fertile couples have focused on the impact of actor depression on QoL, there are growing calls to examine the partner effect of these variables.
As anticipated, females’ depression was higher than their husbands, suggesting that females tend to be more affected by infertility problem than males. This finding is in accordance with the results of previous studies [
18,
19]. However, in two studies conducted in Iran [
20] and Turkey [
21], depression was unrelated to sex. In keeping with previous studies [
22‐
27], females scored lower than their husbands on QoL. In other words, females’ QoL may be more considerably influenced by infertility problem than their husbands.
Based on correlational analysis, high correlation coefficients between males and females’ scores were observed. These confirm that male and female’s scores were adequately related to be deemed statistically non-independent, and so APIM approach would be more appropriate than conventional statistics.
Consistent with previous studies [
5‐
7], the present study showed the considerable actor effect of depression on QoL. In other words, the greater level of depression that is experienced by either males or females with infertility contributes to poorer QoL for each individual.
The key result of the present study was the link between an individual’s depression and his/her spouse’s QoL. In accordance with our expectation, we observed that male’s depression negatively impacted female’s QoL. Contrary to our expectation, our study does not demonstrate a strong partner effect of females’ depression on their husbands’ QoL, although this effect was marginally significant, with P = 0.070.
As mentioned, these results again indicate that infertility and its treatment is shared problem, and so assessing couples from a system perspective can improve the knowledge of psychosocial complexity of infertility and enable health care professionals to develop interventions that help infertile couple manage psychological and social barriers to infertility and its treatment.
Our findings show that both actor and partner effects of depression on QoL were similar for males and females. Although the levels of depression differed between males and females, the associations between depression and QoL were not substantially different between males and females. This finding may indicate that both members of infertile couples share a similar mechanism through which depression influences QoL.
The current study has several limitations that should be mentioned. First, the generalization of the results may be affected by the relatively small sample size and single-center study design. Second, these results were found in a sample of Iranian infertile couples, and therefore may not generalize to other populations with different cultural experience. Third, another limitation of this study is the presence of multicollinearity. The PHQ-9 and FertiQoL tools we have used are significantly correlated, so in some way we are measuring very similar psychological adjustment constructs. Fourth, interactions that might exist between variables were not included in the models. Fifth, because of the cross-sectional nature of the study design, causal inferences between QoL and depression cannot be made. Sixth, this study is based on self-reported data that may be prone to social desirability bias.
Conclusion
In spite of these limitations, the present study has yielded valuable information regarding the actors and partner effects of depression on QoL in male-female dyads experiencing infertility problems. The findings document that both actor and partner effects of depression on QoL are present in infertile couples, supporting the idea that a person’s depression can impact not only their own QoL but also his/her partner’s QoL. Moreover, interventions to reduce depression and to improve QoL should include both males and females. More complex studies in diverse populations and settings, particularly integrating mediation and/or moderation effects, are required to understand the relationship between depression and QoL.
Acknowledgements
The authors express their gratitude to the infertile couples who participated in this study and to the Royan Institute, Tehran, Iran for its kind cooperation in data collection.