Elizabeth O'Brien centres Mexico and highlights clinical knowledge produced by Mexican women, bodies, and health care providers. She says the modern claim about fetal personhood is rooted in surgical force against marginalized and racialized women and that it is the key to understanding obstetric violence and obstetric racism today. O'Brien adds to the historical literature on the medicalized commodification of women's bodies by showing obstetric violence lies at the heart of claims about fetal souls, maternal work, and marginalized groups in national projects in Mexico. She is inspired by the feminist scholarly tradition of writing history through the body.

O'Brien connects the religious origins of caesarean operations in Latin America to modern developments and a chronological broadening of understanding 'meaning-making' in obstetric surgery. There is an emphasis on the theological origins of ideas that add to modern reproductive healthcare tradition that explores how authorities under distinct governments conceived social interventions as pathways to salvation and regeneration.

The book is organized into five chronological sections that address surgery. Each section contains two chapters that historicize reproductive surgery: in theory, policy, and clinical practice. O'Brien is focused on Mexico City because of her source base which draws from a range of religious, medical, and state-based sources such as theological tomes, ecclesiastical records, mission records, and writings by medical students, clinicians, and public health officials.

She uses the word 'experiential' to refer to various procedures. She knows her designations are not straightforward but she does not believe surgery is inherently harmful and does not pass moral judgement on the historical subjects. Women of all racial and social classes are featured in the book because "surgery was a fault line between inclusion, exclusion and embodied prejudice." O'Brien argues Surgeons' and obstetricians' aims were different. Though they both used eugenics to show their subjects were unfit. Surgery was the only way to see an in a womb and a fetus still with its mother.

Surgery and Salvation historicizes debates in one of the most surgically significant countries in the Global South. O'Brien asserts obstetric violence was not worse in the Global South than in the Global North. Mexico was predisposed to medical violence and the history of obstetrics should not fall into narratives about surgical backwardness.