Background: Diaphragmatic hernia (DH) is extremely rarely described during pregnancy. Due to the rarity, there is no diagnostic or treatment algorithm for DH in pregnancy. Aim: To summarize and define the most appropriate diagnostic methods and therapeutic options for DH in pregnancy based on scarce literature. Methods: Literature search of English-, German-, Spanish-, and Italian-language articles were performed using PubMed (1946-2021), PubMed Central (1900-2021), and Google Scholar. The PRISMA protocol was followed. The search terms included: Maternal diaphragmatic hernia, congenital hernia, pregnancy, cardiovascular collapse, mediastinal shift, abdominal pain in pregnancy, hyperemesis, diaphragmatic rupture during labor, puerperium, hernie diaphragmatique maternelle, hernia diafragmática congenital. Additional studies were identified by reviewing reference lists of retrieved studies. Demographic, imaging, surgical, and obstetric data were obtained. Results: One hundred and fifty-eight cases were collected. The average maternal age increased across observed periods. The proportion of congenital hernias increased, while the other types appeared stationary. Most DHs were left-sided (83.8%). The median number of herniated organs declined across observed periods. A working diagnosis was correct in 50%. DH type did not correlate to maternal or neonatal outcomes. Laparoscopic access increased while thoracotomy varied across periods. Presentation of less than 3 days carried a significant risk of strangulation in pregnancy. Conclusion: The clinical presentation of DH is easily confused with common chest conditions, delaying the diagnosis, and increasing maternal and fetal mortality. Symptomatic DH should be included in the differential diagnosis of pregnant women with abdominal pain associated with dyspnea and chest pain, especially when followed by collapse. Early diagnosis and immediate intervention lead to excellent maternal and fetal outcomes. A proposed algorithm helps manage pregnant women with maternal DH. Strangulated DH requires an emergent operation, while delivery should be based on obstetric indications.