English 
Italian I cambiamenti fisiologici dell’ematopoiesi e patologie associate in gravidanza
Physiological changes in hematopoiesis during pregnancy and associated pathologies
AUTORI
1Laboratorio Analisi Chimico-Cliniche, Dipartimento Medicina di Laboratorio e Trasfusionale, Ospedale San Donato, Arezzo
2Laboratorio di Chimica Clinica, Ospedale Maggiore Carità, Dipartimento di Scienze della Salute, Università del Piemonte Orientale, Novara
3Medicina di Laboratorio, IRCCS Ospedale Policlinico San Martino, Genova
ABSTRACT
Physiological changes in hematopoiesis during pregnancy and associated pathologies
Pregnancy is a state characterized by multiple changes at haematological level as a consequence of the physiological adaptation of the organism. This review describes both the physiological modifications that can be observed during pregnancy and the associated pathological conditions as well. The main physiological changes consist in the increa-se of the plasma volume, in the leukocyte and immunological function, in the onset of mild thrombocytopenia and in changes in the coagulation and fibrinolysis systems. During pregnancy, the white blood cell count is increased by 36% compared to the values found in non-pregnant women. In normal pregnancies, the number of neutrophils in all three trimesters is significantly higher than the lymphocyte count, while pregnant women who develop preeclampsia have a lower neutrophil to lymphocyte ratio (NLR) caused by the increase in lymphocytes. Both the increase in plasma volume (approximately 50%), the delayed production and the shorter lifespan of red blood cells cause physiological decreases in hemoglobin and hematocrit, resulting in what is known as “physiological anemia”. Given the increased physiologi-cal demand, the most frequent causes of anemia in pregnancy are those from nutritional deficiencies of iron, folate and vitamin B12. Mean platelet counts decreased during pregnancy in all the women, beginning in the first trimester and continuing throughout pregnancy, with the nadir occurring at the time of delivery. Thrombocytopenia in pregnant patients is due to a number of causes. The clinical laboratory plays a fundamental role in monitoring physiological pregnancy and for detecting pathological conditions that can arise from conception to childbirth.