Background: Unwanted pregnancies cause some type of stress in women, which negatively impacts their way of life. It is important to recognize this type of stress and consider potential interventions. We aimed to comprehend the factors influencing married and parous women’s fertility decisions facing pregnant unintentionally, to provide a reference point for health care, and policy development. Methods: 44 married and parous women with unintended pregnancies who visited a tertiary hospital in Suzhou from May 2021 to July 2021 were chosen using a combination of purposive and theoretical sampling techniques for semi-structured, open-ended interviews. The Lazarus stress-coping model was used to construct the central theme of the analysis, which was “stress-coping style for fertility decision-making among married and parous women with unwanted pregnancy”. The model is divided into three stages: identifying re-fertility stressors, assessing re-fertility coping skills, and making decisions. Results: It takes the combined efforts of society, healthcare, families, and couples to ensure that married and parous women feel secure about having another child. Social support, medical care, and family sharing are all significant factors in the decision to have a child with an unwanted pregnancy. Conclusions: To increase people’s internal motivation to have more children and to support balanced population development, we must first create a healthy and favorable environment for fertility in society.