Background: The diagnosis of hemophagocytic lymphohistiocytosis (HLH) in pregnancy is challenging due to its rarity. There is currently no consensus on the treatment of HLH during pregnancy. We aim to analyze and summarize the clinical characteristics of HLH in pregnancy, and to discuss effective diagnostic and treatment options.Methods: Thirteen patients with HLH during pregnancy who were diagnosed and treated at the Peking Union Medical College Hospital of the Chinese Academy of Medical Sciences from January 2000 to December 2019 were studied retrospectively. We collected data on treatment regimens and on maternal and pregnancy outcomes.Results: All patients had a singleton pregnancy, with a median age of 28 years (range, 22–33 years) and a median gestational age of 23 weeks (7–36 weeks). There were underlying associated diagnoses in six patients; of the patients, 12 (92.3%, 12/13) were treated with corticosteroids, and a good efficiency was achieved in 5 (41.7%, 5/12) of them. Two patients who were treated with dexamethasone and etoposide after termination of pregnancy achieved CR. Two patients attained remission after termination of pregnancy. Four pregnant women died, and the mortality rate was 30.77% (4/13). Fetal or neonatal death up to 1 week after delivery occurred in eight (61.54%) pregnancies, and there were four cases of miscarriage, two of stillbirth, and two of neonatal death. Complications included premature birth (57.14% of neonates), small for gestational age (SGA, 7.70%), premature rupture of membranes (15.38%), and fetal stress (15.38%).Conclusion: Early diagnosis and treatment are important for maternal survival, and corticosteroids are the first choice for most patients with HLH during pregnancy. For patients who do not respond to corticosteroids, etoposide, and termination of pregnancy may be life- saving.