This study aims to evaluate the effectiveness of transtheoretical model (TTM)-based training provided to women with risky lifestyle behaviors during the preconceptional period. The preconceptional period is a critical time for women to modify health behaviors, as addressing these risks early can prevent adverse obstetric outcomes. TTM conceptualizes behavior change as a process and identifies distinct stages individuals progress through during this process. The study examines the impact of TTM-based interventions on improving unhealthy lifestyle behaviors in women before pregnancy.

The preconceptional period is defined as 3 months before pregnancy or at least 1-2 years before the start of unprotected sexual intercourse. Many women enter the pregnancy period with risky living conditions and behaviours including pre-existing physical and behavioural health problems, exposure to teratogenic drugs or adverse environmental conditions, genetic disorders, substance use, unhealthy diet, obesity and domestic violence. It is not possible to correct these risky behaviours which cause many adverse obstetric outcomes in the early periods when pregnancy is not yet noticed. Therefore, many modifiable risky behaviours that may adversely affect outcomes during pregnancy and are difficult to change in the short term should be addressed in the pre-pregnancy period. It is recommended that educational interventions for changing behaviour should be model-based. In this way, it is easier to determine the main factors affecting behaviour, the relationships between these factors and the elements that need to be focused on more. One of the prominent theories that can be taken as a basis for behaviour modification training is the transtheoretical model. The transtheoretical model assumes that individuals go through some stages in the process of changing their health behaviours and maintaining these changes. According to this model, behaviour change is considered as a process rather than a result. One of the prominent theories that can be taken as a basis for behaviour change training is the transtheoretical model. The transtheoretical model assumes that individuals go through some stages in the process of changing their health behaviours and maintaining these changes. According to this model, behaviour change is considered as a process rather than an outcome. This model, developed by Prochaska and DiClemente (1982), basically divides the stage at which the individual is in the change of unhealthy behaviour into five stages temporally. According to this model, people change from people who have no intention to change in adopting new behaviours (pre-planning) to people who think-design to change (planning), to activists who adopt the behaviour but have not yet changed the behaviour regularly (preparation), and to maintainers who have changed the behaviour (action) and continue this behaviour regularly (maintenance). The aim of this study was to determine the effectiveness of transtheoretical model-based training given to women with risky life behaviours in the preconceptional period.

Inclusion Criteria:

Volunteering to participate in the research

• Being between the ages of 18-49 and not going through menopause
• Not having problems in speaking and understanding Turkish
• To be able to read and write
• Being sexually active
• Thinking about becoming pregnant in the next 2 years
• Having the risk score determined from the 'Preconceptional Risky Life Behaviours in Women Diagnostic Scale' to be developed by the researchers

Exclusion Criteria:

• Psychiatric illness
• Having chronic diseases (diabetes, hypertension, hypothyroidism, etc.)