Iron stores in pregnant women with sickle cell disease: a systematic review

Society for Maternal-Fetal Medicine Consult Series #68: Sickle cell disease in pregnancy

Pregnant individuals with sickle cell disease have an increased risk of maternal and perinatal morbidity and mortality. However, prepregnancy counseling and multidisciplinary care can lead to favorable maternal and neonatal outcomes. In this consult series, we summarize what is known about sickle cell disease and provide guidance for sickle cell disease management during pregnancy. The following are Society for Maternal-Fetal Medicine recommendations.

Adverse pregnancy, fetal and neonatal outcomes in women with sickle cell disease in a Middle Eastern country

BACKGROUND

Sickle cell disease in pregnancy is associated with high maternal and fetal mortality. However, studies reporting pregnancy, fetal, and neonatal outcomes in women with sickle cell disease are extremely limited.

OBJECTIVES

The objectives of the study are to determine whether women with sickle cell disease have a greater risk of adverse pregnancy, fetal, and neonatal outcomes than women without sickle cell disease and identify the predictors of adverse pregnancy, fetal, and neonatal outcomes in women with sickle cell disease.

DESIGN

A retrospective pair-matched case-control study was conducted to compare 171 pregnant women with sickle cell disease to 171 pregnant women without sickle cell disease in Muscat, Sultanate of Oman.

METHODS

All pregnant Omani women with sickle cell disease who delivered between January 2015 and August 2021 at Sultan Qaboos University Hospital and Royal Hospital, who were either primipara or multipara and who had a gestational age of 24-42 weeks, were included as patients, whereas women who had no sickle cell disease or any comorbidity during pregnancy, who delivered within the same timeframe and at the same hospitals, were recruited as controls. The data were retrieved from electronic medical records and delivery registry books between January 2015 and August 2021.

RESULTS

Women with sickle cell disease who had severe anemia had increased odds of (χ2 = 58.56, p < 0.001) having adverse pregnancy outcomes. Women with sickle cell disease had 21.97% higher odds of delivering a baby with intrauterine growth retardation (χ2 = 17.80, unadjusted odds ratio = 2.91-166.13, p < 0.001). Newborns born to women with sickle cell disease had 3.93% greater odds of being admitted to the neonatal intensive care unit (χ2 = 16.80, unadjusted odds ratio = 1.97-7.84, p < 0.001). In addition, the children born to women with sickle cell disease had 10.90% higher odds of being born with low birth weight (χ2 = 56.92, unadjusted odds ratio = 5.36-22.16, p < 0.001). Hemoglobin level (odds ratio = 0.17, p < 0.001, 95% confidence interval = 0.10-3.0), past medical history (odds ratio = 7.95, p < 0.001, 95% confidence interval = 2.39-26.43), past surgical history (odds ratio = 17.69, p < 0.001, 95% confidence interval = 3.41-91.76), and preterm delivery (odds ratio = 9.48, p = 0.005, 95% confidence interval = 1.95-46.23) were identified as predictors of adverse pregnancy, fetal, and neonatal outcomes in women with sickle cell disease.

CONCLUSION

As pregnant women with sickle cell disease are at increased risk for pregnancy, fetal, and neonatal adverse outcomes; improved antenatal surveillance and management may improve the outcomes.

A comprehensive view of pregnancy in patients with sickle cell disease in high-income countries: the need for robust data and further decline in morbidity and mortality

Sickle cell disease is a major public health concern due to its prevalence and associated morbidities. In high-income countries, diagnosis and treatment advancements have extended patient's lives and enabled women to embrace motherhood. Although the provision of care in specialist centres has reduced maternal-fetal complication rates, the mortality rate among pregnant women with sickle cell disease remains disproportionately high. Complications arise from vaso-occlusive events, worsening organ damage, thrombotic risks, infections, and pregnancy-related issues, such as pre-eclampsia, premature birth, small-for-gestational-age, and pregnancy loss. Effective management during pregnancy includes preconception planning, genetic counselling, education, and collaborative care. There is no consensus on the overall approach to managing pregnant women with sickle cell disease; however, fostering a collaborative relationship between health-care professionals and researchers is crucial for advancing the understanding and management of this illness. The disparities in health-care outcomes associated with ethnicity and economic insecurity affect patients with sickle cell disease but have not been examined extensively. Hence, health-care personnel need sufficient training to address these issues alongside broader societal efforts to confront racism and discrimination. Comprehensive national and global action plans are required to address the multifaceted challenges of sickle cell disease.

Pregnancy and sickle cell disease: an overview of complications and suggested perinatal care

INTRODUCTION

Pregnancy in women with sickle cell disease (SCD) has been identified as high risk owing to increased incidence of materno-fetal complications across various studies and reports. These complications include consequences related to the underlying hemoglobinopathy; chronic anemia/associated inflammation, and pregnancy related including the risk for thromboembolism, bleeding and maternal mortality. Outcomes of neonates born to women with SCD has been suboptimal over the years with recent improvement due to strict monitoring, preventive and therapeutic measures. Much is yet to be unraveled regarding the optimal management of women with SCD during pregnancy, identifying target hemoglobin, delivery mode or timing among others.

AREAS COVERED

This review includes a summary of available data of the maternal and fetal outcomes; in addition to current recommendations for monitoring and management of women with SCD during pregnancy.

EXPERT OPINION

To have a successful pregnancy, women should be closely monitored, and interventions provided as needed to guarantee adequate management of anemia, as well as prevention, diagnosis and management of disease. They should also be educated regarding their reproductive health, emphasizing that pregnancy is possible, and achieving optimal results depends on providing adequate care in a health care facility with expertise in high-risk pregnancies and SCD.

Iron Metabolism in Normal and Pathological Pregnancies and Fetal Consequences

Iron is required for energy production, DNA synthesis, and cell proliferation, mainly as a component of the prosthetic group in hemoproteins and as part of iron-sulfur clusters. Iron is also a critical component of hemoglobin and plays an important role in oxygen delivery. Imbalances in iron metabolism negatively affect these vital functions. As the crucial barrier between the fetus and the mother, the placenta plays a pivotal role in iron metabolism during pregnancy. Iron deficiency affects 1.2 billion individuals worldwide. Pregnant women are at high risk of developing or worsening iron deficiency. On the contrary, in frequent hemoglobin diseases, such as sickle-cell disease and thalassemia, iron overload is observed. Both iron deficiency and iron overload can affect neonatal development. This review aims to provide an update on our current knowledge on iron and heme metabolism in normal and pathological pregnancies. The main molecular actors in human placental iron metabolism are described, focusing on the impact of iron deficiency and hemoglobin diseases on the placenta, together with normal metabolism. Then, we discuss data concerning iron metabolism in frequent pathological pregnancies to complete the picture, focusing on the most frequent diseases.