Anemia in pregnancy: pathophysiology, diagnosis, and treatment

Impact of Race/Ethnicity and Insurance Status on Obstetric Outcomes: Secondary Analysis of the NuMoM2b Study

OBJECTIVE

 This study aimed to investigate the impact of race/ethnicity and insurance status on obstetric outcomes in nulliparous women.

STUDY DESIGN

 Secondary analysis of the Nulliparous Pregnancy Outcomes Study Monitoring Mothers-To-Be. Obstetric outcomes included the development of a hypertensive event during pregnancy, need for a cesarean section, delivery of a preterm neonate, and postpartum hemorrhage.

RESULTS

 Of 7,887 nulliparous women, 64.7% were non-Hispanic White (White), 13.4% non-Hispanic Black (Black), 17.8% Hispanic, and 4.1% were Asian. Black women had the highest rates of developing new-onset hypertension (32%) and delivering preterm (11%). Cesarean deliveries were the highest in Asian (32%) and Black women (32%). Individuals with government insurance were more likely to deliver preterm (11%) and/or experience hemorrhage after delivery. In multivariable analyses, race/ethnicity was associated with hypertension and cesarean delivery. More important, the adjusted odds ratios for preventable risk factors, such as obesity, diabetes, and severe anemia were greater than the adjusted odds ratios for race/ethnicity in terms of poor maternal outcome.

CONCLUSION

 Although disparities were observed between race/ethnicity and obstetric outcomes, other modifiable risk factors played a larger role in clinical differences.

KEY POINTS

· Race or insurance alone had mixed associations with maternal morbidities.. · Race and insurance had low associations with maternal morbidities.. · Other, modifiable risk factors may be more important.. · Both social and biological factors impact health disparities..

Structures and coordination chemistry of transporters involved in manganese and iron homeostasis

A repertoire of transporters plays a crucial role in maintaining homeostasis of biologically essential transition metals, manganese, and iron, thus ensuring cell viability. Elucidating the structure and function of many of these transporters has provided substantial understanding into how these proteins help maintain the optimal cellular concentrations of these metals. In particular, recent high-resolution structures of several transporters bound to different metals enable an examination of how the coordination chemistry of metal ion-protein complexes can help us understand metal selectivity and specificity. In this review, we first provide a comprehensive list of both specific and broad-based transporters that contribute to cellular homeostasis of manganese (Mn2+) and iron (Fe2+ and Fe3+) in bacteria, plants, fungi, and animals. Furthermore, we explore the metal-binding sites of the available high-resolution metal-bound transporter structures (Nramps, ABC transporters, P-type ATPase) and provide a detailed analysis of their coordination spheres (ligands, bond lengths, bond angles, and overall geometry and coordination number). Combining this information with the measured binding affinity of the transporters towards different metals sheds light into the molecular basis of substrate selectivity and transport. Moreover, comparison of the transporters with some metal scavenging and storage proteins, which bind metal with high affinity, reveal how the coordination geometry and affinity trends reflect the biological role of individual proteins involved in the homeostasis of these essential transition metals.

Antenatal Optimization of Maternal Anemia Leads to Decreased Risks of Maternal Morbidity

Purpose of Review

Our review focuses on the appropriate use of intravenous iron to increase the likelihood of achieving target hemoglobin levels prior to delivery to reduce maternal morbidity.

Recent Findings

Iron deficiency anemia (IDA) is a leading contributor to severe maternal morbidity and mortality. Prenatal treatment of IDA has been demonstrated to reduce the likelihood of adverse maternal outcomes. Recent investigations of intravenous iron supplementation have demonstrated superior efficacy and high tolerability for the treatment of IDA in the third trimester, compared against oral regimens. However, it is unknown whether this treatment is cost-effective, available to clinicians, or acceptable to patients.

Summary

Intravenous iron is superior to the oral treatment of IDA; however, its use is limited by the lack of implementation data.

Correlation between serum ferritin in early pregnancy and hypertensive disorders in pregnancy

Objective

To explore the correlation between serum ferritin (SF) in early pregnancy and the risk of hypertensive disorders in pregnancy (HDP).

Method

A retrospective cohort study was conducted on 43,421 pregnant women with singleton pregnancies who underwent antenatal checkups at Fujian Provincial Maternal and Child Health Hospital from January 2018 to December 2020. Based on pregnancy records, women were classified as non-hypertensive, having gestational hypertension, preeclampsia and preeclampsia with severe features according to the degree of the disease. General baseline data, and SF levels in the early (up to 12 gestational weeks) and late (after 28  weeks of gestation) stages of pregnancy were collected. The significance of the characteristic variables was assessed using a random forest algorithm, and the correlation between early pregnancy SF levels and the incidence of HDP was further analyzed using logistics regression adjusted for confounders. A generalized additive model (GAM) was fitted to a smoothed graph of the relationship between early pregnancy SF levels and HDP, and a threshold effect analysis was performed to find the threshold values of early pregnancy SF for iron supplementation therapy.

Result

A total of 30,703 pregnant women were included. There were 1,103 women who were diagnosed with HDP. Of them, 418 had gestational hypertension, 12 had chronic hypertension without SPE, 332 - preeclampsia and 341 women had preeclampsia with severe features. Levels of SF in early and late pregnancy were significantly higher (p < 0.001) in women with HDP compared to non-hypertensive women and the difference was more pronounced in early pregnancy. The random forest algorithm showed that early pregnancy SF was more effective in predicting HDP compared to late pregnancy SF levels and was also an independent risk factor for HDP (adjusted odds ratio (AOR) = 1.07, 95% CI [1.05,1.09]) after correction for confounding factors. Early pregnancy SF >64.22  mg/l was associated with higher risk of developing hypertensive disorders.

Conclusion

Risk of pregnancy-related hypertensive disorders increases with increasing early pregnancy SF levels. SF levels may therefore be used to further develop guidelines for iron supplementation therapy in pregnant women.

Iron Deficiency in the United States: Limitations in Guidelines, Data, and Monitoring of Disparities

Iron deficiency and the more severe sequela, iron deficiency anemia, are public health problems associated with morbidity and mortality, particularly among pregnant women and younger children. The 1998 Centers for Disease Control and Prevention recommendations for prevention and control of iron deficiency in the United States is old and does not reflect recent evidence but is a foundational reference for many federal, clinical, and program guidelines. Surveillance data for iron deficiency are sparse at all levels, with critical gaps for pregnant women and younger children. Anemia, iron deficiency, and iron deficiency anemia are often conflated but should not be. Clinical guidelines for anemia, iron deficiency, and iron deficiency anemia give inconsistent recommendations, causing nonsystematic assessment of iron deficiency. Screening for iron deficiency typically relies on identifying anemia, despite anemia's low sensitivity for iron deficiency. In the National Health and Nutrition Examination Survey, more than 70% of iron deficiency is missed among pregnant women and children by relying on hemoglobin for iron deficiency screening. To improve assessment and diagnosis and strengthen surveillance, better and more complete data and updated foundational guidance on iron deficiency and anemia are needed that consider new evidence for measuring and interpreting laboratory results. (Am J Public Health. 2022;112(S8):S826-S835. https://doi.org/10.2105/AJPH.2022.306998).

Addressing the gaps in nutritional care before and during pregnancy

The present paper outlines current issues in the nutritional care of women during pregnancy and potential resources to address them. Globally, overnutrition, undernutrition and nutritional imbalances are widespread among women of reproductive age; increasing the risk of pregnancy complications and non-communicable diseases in both mothers and their children. Most women do not meet dietary guidelines for pregnancy. The World Health Organisation (WHO) recommends nutrition and weight counselling during pregnancy for all women. However, clinical practices focusing on nutrition vary and there is no consensus on which outcomes are most important for pregnancy nutrition interventions, with little consideration for the 'patient voice'. The International Federation of Gynaecology and Obstetrics (FIGO) nutrition checklist is a clinical practice tool that is available for healthcare professionals that will address this issue. The pregnancy nutrition core outcome set will also support advancement of antenatal nutrition by identifying the most critical nutrition-related outcomes from the perspective of healthcare professionals, researchers and women with experience of pregnancy. While poor nutrition can result in adverse outcomes across women of all weight categories, those with obesity may require specialist care to reduce their risk. Obesity is a chronic, progressive, relapsing disease that has high individual variability in its prognosis. The use of obesity staging systems, which consider mental, physical and functional health, can stratify individuals into risk categories and aid in treatment prioritisation in pregnancy. As the prevalence of obesity continues to rise, an obesity staging approach may support clinicians, especially those in limited resource settings.