Effect of a Training Intervention Based on the Theory of Planned Behavior on the Pregnancy Intention in Women with One Child: A Training Trial

Background: Having an only child has positive and negative consequences for the health of the child, mother, and family. However, when one-child families become the norm, the risks of negative long-term impacts increase. In Iran, couples now prefer to have one child. This paper reports on an investigation into the effectiveness of training based on the theory of planned behavior (TPB) on the pregnancy intention in women with one child. Methods: The trial was conducted in 2019 with 102 women with one child, who was supported by the Health Centers in Qom, Iran. They were randomly divided into two groups: TPB theory-based training (n = 52) and control (routine healthcare training, n = 50) groups. ANCOVA was used to compare the groups' post-training pregnancy intention and its theoretical antecedents. Results: Three months post-training, participants in the TPB group had higher pregnancy intention (η² = .4, P<0.001), attitude to having a second child (η² = .41, P<0.001), subjective (perceived) norm for having a second child (η² = .08, P<0.004), and perceived control for having a second child (η² = .35, P<0.001). The TPB-based training intervention increased women's awareness of the consequences of having an only child significantly more than routine training (P<0.001). Conclusion: Health center training can increase women's intention to have a second child. In this trial, theory-based training resulted in stronger pregnancy intention than participation in routine training. As health centers in Iran update their programs, this trial highlights the value of course design based on established theory.