Pregnancy is a natural and pleasant event for many females. Pregnancy and the course of becoming parents involve many life changes that might embrace vulnerable phases of psychological well-being problems. In some females, there may be a mental obstruction, such as depression, anxiety, tension, and other emotional instabilities. This chapter scrutinizes the psychosocial prognosticators of mental well-being among pregnant females and their newborns’ birth weight. The study used the State-Trait Inventory for Cognitive and Somatic Anxiety (STICSA), the Pain Catastrophizing Scale (PCS), the Relationship Assessment Scale (RAS), the Childbirth Attitudes Questionnaire, the Karachi Domestic Violence Screening Questionnaire, the Multidimensional Scale of Perceived Social Support, and the Pakistan Anxiety and Depression Scale upon a sample of 136 pregnant females for constructs measurement. Findings revealed that anxiety proneness was positively associated with childbirth fear and depression; however, they had no link with newborns’ weight at birth. Pain catastrophizing plus domestic violence were positively allied with childbirth fear plus depression, although they were negatively allied with the birth of newborns. Matrimonial satisfaction plus social support had a negative alliance with childbirth fear and depression but had a positive link with newborns’ weight at birth. Regression scrutiny showed that anxiety proneness was the significant prognosticator of high childbirth fear and depression. Pain catastrophizing and domestic violence were significant predictors of high childbirth dread and depression, but they forecasted low newborns’ weight at birth. Matrimonial satisfaction and social support were substantial predictors of low childbirth fear and depression, while they were positive prognosticators of newborns’ weight at birth.