During pregnancy, the maternal organism undergoes profound physiological changes, which directly affect the biochemical, hematological, and serological profile. The identifying and monitoring of these changes are imperative to ensure maternal well-being and healthy fetal development.

To undertake a theoretical investigation of the primary laboratory modifications observed during pregnancy, drawing upon national and international scientific literature.

This is a descriptive and qualitative narrative literature review. A comprehensive review of the literature was conducted on the subject of physiological and pathological laboratory alterations in pregnant women. The review included articles published between 2010 and 2023 in Portuguese, English, and Spanish. The descriptors employed included: The following terms are relevant to the study:: “pregnancy,” “biochemical profile,” “hematological profile,” “pregnancy serology,” and “prenatal care.”

As demonstrated in extant literature, during the course of pregnancy, there is an expansion of plasma volume, which leads to what is referred to as physiological anemia of pregnancy. This condition is, characterized by hemodilution and a relative reduction in hemoglobin levels. From a biochemical perspective, alterations are observed in levels of urea, creatinine, blood glucose and liver enzymes. These alterations should be interpreted in light of gestational adaptations. In terms of serology, it is essential to screen for vertically transmitted infections such as HIV, syphilis, toxoplasmosis, hepatitis B and C, and rubella as pose significant risks to fetal health. The presence of IgG and IgM antibodies indicates previous exposure or active infection, which is crucial for proper clinical management during prenatal care.

A comprehensive understanding of the physiological laboratory changes associated with pregnancy enables the discernment of pathological conditions necessitating clinical intervention. Misinterpretation of these tests may result in unintended consequences or detrimental omissions. The review highlights the need for health professionals engaged in prenatal care to receive training in the critical evaluation of laboratory data, taking into account gestational age, the clinical condition of the pregnant woman, and the protocols recommended by national guidelines.

The theoretical approach to the biochemical, hematological, and serological profile of pregnant women contributes to the understanding of expected laboratory parameters during pregnancy and underscores the importance of continuous monitoring. Interdisciplinary action, in conjunction with ongoing professional education, is essential to ensure the provision of qualified, safe, and evidence-based prenatal care.