Maternal and Perinatal Morbidity and Mortality Associated With Anemia in Pregnancy

OBJECTIVE To estimate the incidence of anemia in pregnancy and compare the maternal and perinatal outcomes of women with and without anemia. METHODS We conducted a population-based retrospective cohort study on all pregnant women in British Columbia who had a live birth or stillbirth at or after 20 weeks of gestation between 2004 and 2016. Women were diagnosed with anemia based on two criteria: third-trimester hemoglobin value or a delivery admission diagnosis of anemia (made before delivery). Anemia was categorized into no anemia (hemoglobin 11 g/dL or greater), mild (9-10.9 g/dL), moderate (7-8.9 g/dL), severe (less than 7 g/dL), or anemia of unspecified severity (with diagnosis made before delivery). Logistic regression was used to estimate adjusted odds ratios (aOR) and 95% CIs expressing the association between anemia and maternal and perinatal outcomes. RESULTS Of 515,270 women in the study population, 65,906 (12.8%) had anemia: 11.8%, 0.43%, and 0.02% had mild, moderate, and severe anemia, respectively, and 0.58% had anemia of unspecified severity. Anemic women had longer hospitalization duration and more antenatal admissions, and rates of preeclampsia, placenta previa and cesarean delivery were higher among women with anemia. The intrapartum-postpartum blood transfusion rate was 5.1 per 1,000 among women without anemia, and higher among women with anemia (aOR 2.45, 95% CI 1.74-3.45 for mild anemia; 21.3, 95% CI 12.2-37.3 for moderate anemia; not analyzable for severe anemia; and 48.3, 95% CI 6.60-353.9 for anemia of unspecified severity). Anemia was associated with preterm birth (mild anemia, aOR 1.09, 95% CI 1.05-1.12; moderate anemia, aOR 2.26, 95% CI 2.02-2.54; anemia of unspecified severity, aOR 2.27, 95% CI 2.06-2.50), small-for-gestational-age live birth, low 5-minute Apgar score, neonatal death, and perinatal death. CONCLUSION Maternal anemia in pregnancy represents a common and potentially reversible risk factor associated with antepartum, intrapartum, and postpartum maternal morbidity and perinatal morbidity and mortality.

[1]  Joshua I. Rosenbloom,et al.  Expectant Management of Hypertensive Disorders of Pregnancy and Future Cardiovascular Morbidity. , 2019, Obstetrics and gynecology.

[2]  K. Joseph,et al.  Maternal and Perinatal Morbidity and Mortality Associated With Anemia in Pregnancy , 2019, Obstetrics and gynecology.

[3]  Erkan Kalafat,et al.  Cardiovascular System in Preeclampsia and Beyond , 2019, Hypertension.

[4]  H. Kehlet,et al.  International consensus statement on the peri‐operative management of anaemia and iron deficiency , 2017, Anaesthesia.

[5]  M. Metra,et al.  Insights into cardiac alterations after pre‐eclampsia: an echocardiographic study , 2017, Ultrasound in obstetrics & gynecology : the official journal of the International Society of Ultrasound in Obstetrics and Gynecology.

[6]  M. Metra,et al.  Endothelial dysfunction and vascular stiffness in women with previous pregnancy complicated by early or late pre‐eclampsia , 2017, Ultrasound in obstetrics & gynecology : the official journal of the International Society of Ultrasound in Obstetrics and Gynecology.

[7]  A. Biler,et al.  Can anemia predict perinatal outcomes in different stages of pregnancy? , 2016, Pakistan journal of medical sciences.

[8]  L. De‐Regil,et al.  Daily oral iron supplementation during pregnancy. , 2015, The Cochrane database of systematic reviews.

[9]  F. Jamali,et al.  Impact of Preoperative Anaemia and Blood Transfusion on Postoperative Outcomes in Gynaecological Surgery , 2015, PloS one.

[10]  Lily S Lee,et al.  Validating the British Columbia Perinatal Data Registry: a chart re-abstraction study , 2015, BMC Pregnancy and Childbirth.

[11]  M. Metra,et al.  Elastic properties of ascending aorta in women with previous pregnancy complicated by early‐ or late‐onset pre‐eclampsia , 2015, Ultrasound in obstetrics & gynecology : the official journal of the International Society of Ultrasound in Obstetrics and Gynecology.

[12]  W. Fawzi,et al.  Anaemia, prenatal iron use, and risk of adverse pregnancy outcomes: systematic review and meta-analysis , 2013, BMJ.

[13]  P. Austin,et al.  Surgical outcomes and transfusion of minimal amounts of blood in the operating room. , 2012, Archives of surgery.

[14]  I. Adam,et al.  Severe anaemia is associated with a higher risk for preeclampsia and poor perinatal outcomes in Kassala hospital, eastern Sudan , 2011, BMC Research Notes.

[15]  O. Miettinen.  Up from Clinical Epidemiology & EBM , 2011 .

[16]  G. Lindmark,et al.  Risks for preterm delivery and low birth weight are independently increased by severity of maternal anaemia. , 2009, South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde.

[17]  Z. Li,et al.  Low first‐trimester hemoglobin and low birth weight, preterm birth and small for gestational age newborns , 2007, International journal of gynaecology and obstetrics: the official organ of the International Federation of Gynaecology and Obstetrics.

[18]  J. Bailit,et al.  Repeated hematocrit measurements in low-risk pregnant women. , 2007, The Journal of reproductive medicine.

[19]  K. Joseph,et al.  Socioeconomic Status and Receipt of Obstetric Services in Canada , 2006, Obstetrics and gynecology.

[20]  P. Elliott,et al.  Hemoglobin concentration in pregnancy and perinatal mortality: a London-based cohort study. , 2005, American journal of obstetrics and gynecology.

[21]  Robert W Platt,et al.  Regression models for clustered binary responses: implications of ignoring the intracluster correlation in an analysis of perinatal mortality in twin gestations. , 2005, Annals of epidemiology.

[22]  R W Platt,et al.  A new and improved population-based Canadian reference for birth weight for gestational age. , 2001, Pediatrics.

[23]  D. Pelletier,et al.  An analysis of anemia and pregnancy-related maternal mortality. , 2001, The Journal of nutrition.

[24]  J. Concato,et al.  A simulation study of the number of events per variable in logistic regression analysis. , 1996, Journal of clinical epidemiology.

[25]  P. Steer,et al.  Relation between maternal haemoglobin concentration and birth weight in different ethnic groups , 1995, BMJ.

[26]  R. Newcombe,et al.  RELATION OF HAEMOGLOBIN LEVELS IN FIRST AND SECOND TRIMESTERS TO OUTCOME OF PREGNANCY , 1986, The Lancet.

[27]  S. Zeger,et al.  Longitudinal data analysis using generalized linear models , 1986 .

[28]  D. Bereczki,et al.  The Cochrane Database of Systematic Reviews , 2003 .

[29]  C. Weinberg,et al.  Use and misuse of population attributable fractions. , 1998, American journal of public health.

[30]  J. Selby,et al.  Anemia and spontaneous preterm birth. , 1991 .

[31]  Drs Du Buisson,et al.  Iron deficiency anaemia. , 1973, Nursing times.