Contemporary uses of erythropoietin in pregnancy: a literature review

Recombinant erythropoietin for the treatment of iron deficiency anemia in pregnancy: A systematic review

BACKGROUND

Treatment options for severe, refractory iron deficiency anemia are limited in pregnancy.

OBJECTIVE

To review the available literature on the use of recombinant erythropoietin in the treatment of iron deficiency anemia in pregnancy.

SEARCH STRATEGY

An electronic search of seven databases from inception to March 2022 was performed using a combination of keywords.

SELECTION CRITERIA

We included all randomized controlled or observational studies of pregnant patients with iron deficiency anemia who received recombinant erythropoietin or control. The primary outcome was a change in hematologic parameters (hemoglobin or hematocrit) after treatment. Studies were appraised using the criteria outlined in the Cochrane Handbook for Systematic Reviews of Interventions.

DATA COLLECTION AND ANALYSIS

Data were summarized using narrative synthesis and descriptive statistics as appropriate. This study was registered with PROSPERO, CRD42022313328.

MAIN RESULTS

Of 234 studies screened, five studies met the inclusion criteria and had sufficient data for analysis (n = 103 recombinant erythropoietin and n = 104 controls). All patients in the intervention group received iron supplementation (intravenous or oral) in addition to recombinant erythropoietin. All patients in the control group received iron supplementation (intravenous or oral) alone. As the result of variance between studies in inclusion criteria, the timing of repeat blood draws, and data reporting, a meta-analysis could not be performed. Three studies found that serial recombinant erythropoietin combined with iron supplementation was more effective at raising hematologic laboratory parameters (hemoglobin or hematocrit) than iron alone. One study reported no difference in hemoglobin or hematocrit levels between groups at day 28. However, patients in this study only received one dose of recombinant erythropoietin, whereas those in the other studies received serial doses. Another study also found no difference in hemoglobin levels by day 28, but patients in the recombinant erythropoietin group had lower hemoglobin levels at baseline and a more rapid rise in hemoglobin than iron alone. This is demonstrated by a more significant rise in hemoglobin at day 11 in the recombinant erythropoietin group than in the control group.

CONCLUSIONS

Serial recombinant erythropoietin administration and iron supplementation may be more effective at treating refractory iron deficiency anemia in pregnancy than iron supplementation alone.

Anemia in Pregnancy With CKD

Chronic kidney disease (CKD), anemia, and iron deficiency are global health issues affecting individuals in both high-income and low-income countries. In pregnancy, both CKD and iron deficiency anemia increase the risk of adverse maternal and neonatal outcomes, including increased maternal morbidity and mortality, stillbirth, perinatal death, preterm birth, and low birthweight. However, it is unknown to which extent iron deficiency anemia contributes to adverse outcomes in CKD pregnancy. Furthermore, little is known regarding the prevalence, pathophysiology, and treatment of iron deficiency and anemia in pregnant women with CKD. Therefore, there are many unanswered questions regarding optimal management with oral or i.v. iron and recombinant human erythropoietin (rhEPO) in these women. In this review, we present a short overview of the (patho)physiology of anemia in healthy pregnancy and in people living with CKD. We present an evaluation of the literature on iron deficiency, anemia, and nutritional deficits in pregnant women with CKD; and we evaluate current knowledge gaps. Finally, we propose research priorities regarding anemia in pregnant women with CKD.

Breast cancer during pregnancy: epidemiology, phenotypes, presentation during pregnancy and therapeutic modalities

Although it is uncommon in general, breast cancer is the most commonly diagnosed cancer during pregnancy. While treatment for pregnant patients should adhere to treatment guidelines for non-pregnant patients, there exist specific considerations concerning diagnosis, staging, oncological treatment, and obstetrical care. Imaging and staging are preferably performed using breast ultrasound and mammography. Other ionizing radiation imaging modalities, including computed tomography (CT) and Positron Emission Tomography/ Computed Tomography (PET/CT), can be selectively performed when the estimated benefit for the mother outweighs the risks to the foetus, e.g., when the results will change clinical management. MRI is appropriate to stage for distant disease on the indication. Breast cancer during pregnancy is less often hormone receptor-positive and more frequently triple-negative breast cancer compared to age-matched controls. The basic principle is that women should receive state-of-the-art oncological treatment without delay if possible and that the pregnancy should be maintained as long as possible. Treatment strategy should be multidisciplinary defined, carefully weighing the selection, sequence, and timing of treatment modalities depending on patient-, tumour-, and pregnancy-related characteristics, as well as patient preferences. Initiating cancer treatment during pregnancy often decreases the risks of early delivery and prematurity. Breast cancer surgery is possible during all trimesters. Radiotherapy is possible during pregnancy in the first half of pregnancy. Chemotherapy can be safely administered starting from 12 weeks of gestational age, but endocrine and HER2 targeted therapy are contraindicated throughout the whole pregnancy. Importantly, foetal growth should be monitored and long-term follow-up of the children is encouraged in dedicated centres.

An evidence-based definition of anemia for singleton, uncomplicated pregnancies

Background

The definition for anemia in pregnancy is outdated, derived from Scandinavian studies in the 1970’s to 1980’s. To identity women at risk of blood transfusion, a common cause of Severe Maternal Morbidity, a standard definition of anemia in pregnancy in a modern, healthy United States cohort is needed.

Objective

To define anemia in pregnancy in a United States population including a large county vs. private hospital population using uncomplicated patients.

Materials and methods

Inclusion criteria were healthy women with the first prenatal visit before 20 weeks. Exclusion criteria included preterm birth, preeclampsia, hypertension, diabetes, short interval pregnancy (<18 months), multiple gestation, abruption, and fetal demise. All women had iron fortification (Ferrous sulfate 325 mg daily) recommended. The presentation to care and pre-delivery hematocrits were obtained, and the percentiles determined. A total of 2000 patients were included, 1000 from the public county hospital and 1000 from the private hospital. Each cohort had 250 patients in each 2011, 2013, 2015, and 2018. The cohorts were compared for differences in the fifth percentile for each antepartum epoch. Student’s t-test and chi-squared statistical tests were used for analysis, p-value of ≤0.05 was considered significant.

Results

In the public and private populations, 777 and 785 women presented in the first trimester while 223 and 215 presented in the second. The women at the private hospital were more likely to be older, Caucasian race, nulliparous, and present earlier to care. The fifth percentile was compared between the women in the private and public hospitals and were clinically indistinguishable. When combining the cohorts, the fifth percentile for hemoglobin/hematocrit was 11 g/dL/32.8% in the first trimester, 10.3 g/dL/30.6% in the second trimester, and 10.0 g/dL/30.2% pre-delivery.

Conclusions

Fifth percentile determinations were made from a combined cohort of normal, uncomplicated pregnancies to define anemia in pregnancy. Comparison of two different cohorts confirms that the same definition for anemia is appropriate regardless of demographics or patient mix.

Iron Deficiency Anemia in Pregnancy

Anemia is defined as a low red blood cell count, a low hematocrit, or a low hemoglobin concentration. In pregnancy, a hemoglobin concentration of less than 11.0 g/dL in the first trimester and less than 10.5 or 11.0 g/dL in the second or third trimester (depending on the guideline used) is considered anemia. Anemia is the most common hematologic abnormality in pregnancy. Maternal anemia is associated with adverse fetal, neonatal and childhood outcomes, but causality is not established. Maternal anemia increases the likelihood of transfusion at delivery. Besides hemodilution, iron deficiency is the most common cause of anemia in pregnancy. The American College of Obstetricians and Gynecologists recommends screening for anemia with a complete blood count in the first trimester and again at 24 0/7 to 28 6/7 weeks of gestation. Mild anemia, with a hemoglobin of 10.0 g/dL or higher and a mildly low or normal mean corpuscular volume (MCV) is likely iron deficiency anemia. A trial of oral iron can be both diagnostic and therapeutic. Mild anemia with a very low MCV, macrocytic anemia, moderate anemia (hemoglobin 7.0-9.9 g/dL) or severe anemia (hemoglobin 4.0-6.9 g/dL) requires further investigation. Once a diagnosis of iron deficiency anemia is confirmed, first-line treatment is oral iron. New evidence suggests that intermittent dosing is as effective as daily or twice-daily dosing with fewer side effects. For patients with iron deficiency anemia who cannot tolerate, cannot absorb, or do not respond to oral iron, intravenous iron is preferred. With contemporary formulations, allergic reactions are rare.

Anaemia in chronic kidney disease pregnancy

AIM

To review the incidence and management of anaemia and outcomes in pregnancies in a cohort of Australian women with chronic kidney disease.

METHODS

A retrospective audit of 63 pregnancies in 52 women with chronic kidney disease.

RESULTS

Sixty-eight percent of chronic kidney disease pregnancies were complicated by haemoglobin less than 100 g/L. Iron stores were measured in only 62% of all pregnancies. Serum ferritin was less than 100 ng/ml in 95% of those tested. Erythropoietin-stimulating agents were used in 24 pregnancies (38%). Intravenous iron was used in only nine non-dialysis pregnancies.

CONCLUSION

Greater awareness of the importance of regular measurement of iron stores and appropriate levels for repletion in chronic kidney disease pregnancies amongst health professionals involved in obstetric care may result in earlier detection and treatment of iron deficiency, and potentially improve maternal and fetal outcomes.

End-Stage Kidney Disease and Dialysis in Pregnancy

End-stage kidney disease is associated with low fertility, with rates of conception in women on dialysis estimated at 1/100th of the general population. However, live birth rates are increasing over time in women on hemodialysis, whereas they remain lower and static in women on peritoneal dialysis. Intensification of hemodialysis, targeting a serum blood urea nitrogen <35 mg/dL or 36 hours of dialysis per week in women with no residual kidney function, is associated with improved live birth rates and longer gestational age. Even in intensively dialyzed cohorts, rates of prematurity and need for neonatal intensive care are high, upwards of 50%. Although women on peritoneal dialysis in pregnancy do not appear to be at increased risk of delivering preterm compared with those on hemodialysis, their infants are more likely to be small for gestational age. As such, hemodialysis has emerged as the preferred dialysis modality in pregnancy. Provision of specialized nephrology, obstetric, and neonatal care is necessary to manage these complex pregnancies and family planning counseling should be offered to all women with end-stage kidney disease.

Intrapartum Management of Sickle Cell Anemia With Rare Antibody and Minimal Blood Availability

Sickle cell disease (SCD) can pose serious maternal and fetal risk in pregnancy. Transfusion, both during and outside of pregnancy, can improve patient morbidity and mortality but carries risk of alloimmunization, complicating future management. This case describes a 29-year-old gravida 1, para 0 woman with sickle cell anemia and rare red blood cell alloantibody (anti-Rh46) who presented with severe vaso-occlusive crisis at 29 weeks with hemoglobin of 7.6 g/dL. Only one unit of compatible blood existed in the country. Planning for transfusion with least-incompatible blood was made. She ultimately underwent cesarean section at 31 weeks and 2 days for abnormal fetal testing. This case highlights that blood products should be utilized judiciously because their adverse effects, like alloimmunization, can increase patient morbidity and mortality.

Management of patients with rare blood groups in maternity

We report on our experiences since 2010 with pregnant women with rare blood types. The lack of compatible blood is a challenge for the anaesthetist whose priority is to prevent and treat anaemia in late pregnancy in order to avoid immunisation after transfusion of incompatible blood. In our hospital, the blood type is checked during the first obstetric consult, which is variable, starting from the fourth month of pregnancy. Rare blood types are most often diagnosed in an advanced stage of pregnancy (30 weeks of gestation: WG) due to the late inscription for obstetrics consult, resulting in even later anaesthetic visit. In our 13 patients, the most common blood systems are Duffy, MNS, and RH. 61.5% of the patients have associated antibodies (anti-MNS5). The majority of patients received iron with significant increase of ferritin (17.24 ± 12.95 μg/L versus 262.2 ± 404.4 μg/L, p = .033). Six of the patients had 2-3 injections of EPO between 29 - 36 + 1 WG. There were no transfers for paediatric management of haemolytic disease in the newborn following the birth. Overall, this treatment of patients with a rare blood group has also changed our practices for the follow-up of other pregnant women, and ferritin is more regularly prescribed.Impact statementWhat is already known on this subject? For rare blood groups, the frequency in the general population is less than 1/4000. The most common antibodies at risk of haemolytic disease and 'hydrops fetalis' are anti-D, anti-E, anti-C, and anti-K. The survey of pregnant women with a rare blood type takes into account the maternal risk of 'transfusion deadlock' and haemolytic disease of the newborn.What do the results of this study add? Rare blood types are most often diagnosed in an advanced stage of pregnancy (30 WG) due to the late inscription for obstetrics consults at Maternity. The most common blood systems are Duffy, MNS, RH, and 61.5% of the patients have associated antibodies (anti-MNS5). The most efficient treatment of prenatal anaemia was iron perfusions who allowed significant increase of ferritin and a maternal haemoglobin concentration of 12.1±1.46 g/dL in the ninth month of pregnancy.What are the implications of these findings for clinical practice and/or further research? A pregnant woman with a rare blood group is a situation that requires a technical platform specialised in haemorrhagic risk and a multidisciplinary team, including a blood bank as well as anaesthetic and obstetrical teams, with excellent interdisciplinary coordination.

Drugs in renal disease and pregnancy

This review aims to summarise historic and the latest evidence of commonly used drugs in pregnant women with chronic kidney disease (CKD). Data regarding safety of drugs in breastfeeding are also described. Practical recommendations are made on the use of newer agents that have limited information of use in pregnant women with CKD. Pharmacokinetic and dynamic issues are outlined, and general principles for prescribing drugs in pregnant women with CKD are listed. Resources to investigate drug safety are presented.

The Levels of Hepcidin and Erythropoietin in Pregnant Women with Anemia of Various Geneses

AIM:

The purpose of the present research was to study the content of erythropoietin and hepcidin in serum in pregnant women with iron deficiency anaemia and anaemia of chronic inflammation.

METHODS:

The authors examined 98 pregnant women who were observed in LLP (Regional obstetric-gynaecological centre) in Karaganda. The including criteria for pregnant women in the study was the informed consent of the woman to participate in the study. Exclusion criteria were oncological diseases, HIV-infection, tuberculosis, severe somatic pathology, mental illness, drug addiction. The design of the study was by the legislation of the Republic of Kazakhstan, international ethical norms and normative documents of research organisations, approved by the ethics committee of the Karaganda State Medical University.

RESULTS:

As a result of the study, it was determined that the content of erythropoietin and hepcidin in pregnant women with anemias of different genesis varies ambiguously. In the main group of pregnant women with IDA, the erythropoietin content rises, and the hepcidin level decreases. In pregnant women with ACI, on the contrary, the level of hepcidin increases, and in one subgroup it is significant. However, in pregnant women and with IDA and anemia of chronic inflammation, there is a subgroup of women in whom erythropoietin is either comparable with hepcidin, or their changes are of opposite nature.

CONCLUSION:

The authors concluded that the obtained data indicate ambiguous changes in the level of erythropoietin and hepcidin in pregnant women with anaemias of various origins. In all likelihood, there are still unaccounted factors affecting the content of these protein-regulators of iron metabolism, which require further definition and interpretation in anaemia of pregnant women.

Applying a weight of evidence approach to the evaluation of developmental toxicity of biopharmaceuticals

Toxicity studies in pregnant animals are not always necessary for assessing the human risk of developmental toxicity of biopharmaceuticals. The growing experience and information on target biology and molecule-specific pharmacokinetics present a powerful approach to accurately anticipate effects of target engagement by biopharmaceuticals using a weight of evidence approach. The weight of evidence assessment should include all available data including target biology, pharmacokinetics, class effects, genetically modified animals, human mutations, and a thorough literature review. When assimilated, this weight of evidence evaluation may be sufficient to inform risk for specific clinical indications and patient populations. While under current guidance this approach is only applicable for drugs and biologics for oncology, the authors would like to suggest that this approach may also be appropriate for other disease indications. When there is an unacceptable level of uncertainty and a toxicity study in pregnant animals could impact human risk assessment, then such studies should be considered. Determination of appropriate nonclinical species for developmental toxicity studies to inform human risk should consider species-specific limitations, reproductive physiology, and pharmacology of the biopharmaceutical. This paper will provide considerations and examples of the weight of evidence approach to evaluating the human risk of developmental toxicity of biopharmaceuticals.

Management of Iron Deficiency Anemia in Pregnancy in India

Iron deficiency anemia (IDA) continues to be the commonest etiology of anemia in pregnancy. The prevalence of iron deficiency (ID) in pregnant Indian women is amongst the highest in the world. Untreated iron deficiency (ID) has significant adverse feto-maternal consequences. Plethora of investigations are available for diagnosis of IDA, each having specific advantages and disadvantages when used in the pregnancy setting. Therapy for ID includes dietary modification, oral iron supplementation, intravenous iron and blood transfusion. Newer parenteral iron preparations are safe and there is mounting evidence to suggest their use in frontline settings for pregnancy associated IDA in the second and third trimester. Through this review, we suggest an algorithm for diagnosis and treatment of IDA in pregnancy depending on the severity of anemia and period of gestation suited for widespread use in resource limited settings. Also, we recommend ways for increasing public awareness and tackling this health issue including the observance of "National Anemia Awareness and Treatment Day."

Treatment of gynecological cancers diagnosed during pregnancy

Because of a notable increase in age at delivery, the incidence of malignancy diagnosed during pregnancy has substantially increased. This review aims to summarize the literature and expert knowledge on gynecologic cancers diagnosed in pregnancy regarding epidemiology, examination and staging procedures, description of treatment modalities and management of gynecological malignancies with special interest in cervical and ovarian cancer. Thorough attention is paid to the surgery and chemotherapy administration for early-stage cervical cancer diagnosed during pregnancy.

Efficacy and safety of adjuvant recombinant human erythropoietin and ferrous sulfate as treatment for iron deficiency anemia during the third trimester of pregnancy

PURPOSE

Gestational anemia increases the incidence of maternal and fetal complications. Adjuvant recombinant human erythropoietin (rHuEPO) has been used in patients who refuse blood transfusions, have a low response to treatment with iron sulfate, have limited time before birth, or have other illnesses that complicate the anemia. We demonstrated that the use of adjuvant rHuEPO with iron sulfate reduces the anemia time period and is innocuous to the fetus.

METHOD

An experimental longitudinal prospective study; 100 pregnant women in their third trimester were included. Group 1 (n=50) was set as control for prevalence of anemia and establish hematological maternal and fetal parameters at delivery for our population; 50 women diagnosed with iron deficiency anemia were randomly assigned to treatment groups. Group 2 (n=25) third trimester women with a hemoglobin of <11g/dL were treated with iron sulfate, 600mg administered orally daily for 4 weeks, evaluating the hematologic response for the mother weekly and for both mother and fetus at birth; Group 3 (n=25) women similar to group 2, treated in addition with adjuvant rHuEPO, 4000 units subcutaneously, three times a week, for 4 weeks evaluating the same parameters.

RESULTS

Group 2 and 3 showed a corrected anemia before delivery (mean 11.1 vs 11.4g/dL), but Group 3 showed a statistically broader and more rapid increase in hemoglobin (1.22 vs 1.92g/dL, p value 0.013) with an rHuEPO dose of 4000 units, three times a week for 1 month. No clinical or hematologic difference or changes in growth were observed in the fetus.

CONCLUSIONS

Erythropoietin is safe and effective for both mother and fetus, although an ideal pregnancy dose has not yet been established.

Best practices on pregnancy on dialysis: the Italian Study Group on Kidney and Pregnancy

BACKGROUND

Pregnancy during dialysis is increasingly being reported and represents a debated point in Nephrology. The small number of cases available in the literature makes evidence-based counselling difficult, also given the cultural sensitivity of this issue. Hence, the need for position statements to highlight the state of the art and propose the unresolved issues for general discussion.

METHODS

A systematic analysis of the literature (MESH, Emtree and free terms on pregnancy and dialysis) was conducted and expert opinions examined (Study Group on Kidney and Pregnancy; experts involved in the management of pregnancy in dialysis in Italy 2000-2013). Questions regarded: timing of dialysis start in pregnancy; mode of treatment, i.e. peritoneal dialysis (PD) versus haemodialysis (HD); treatment schedules (for both modes); obstetric surveillance; main support therapies (anaemia, calcium-phosphate parathormone; acidosis); counselling tips.

MAIN RESULTS

Timing of dialysis start is not clear, considering also the different support therapies; successful pregnancy is possible in both PD and HD; high efficiency and strict integration with residual kidney function are pivotal in both treatments, the blood urea nitrogen test being perhaps a useful marker in this context. To date, long-hour HD has provided the best results. Strict, personalized obstetric surveillance is warranted; therapies should be aimed at avoiding vitamin B12, folate and iron deficits, and at correcting anaemia; vitamin D and calcium administration is safe and recommended. Women on dialysis should be advised that pregnancy is possible, albeit rare, with both types of dialysis treatment, and that a success rate of over 75% may be achieved. High dialysis efficiency and frequent controls are needed to optimize outcomes.

Maternal inflammation at delivery affects assessment of maternal iron status

Pregnant adolescents (aged ≤ 18 y, n = 253) were followed from ≥ 12 wk of gestation to delivery to assess longitudinal changes in anemia and iron status and to explore associations between iron status indicators, hepcidin, and inflammatory markers. Hemoglobin, soluble transferrin receptor (sTfR), ferritin, serum iron, erythropoietin (EPO), hepcidin, C-reactive protein, interleukin-6 (IL-6), folate, and vitamin B-12 were measured, and total body iron (TBI) (milligrams per kilogram) was calculated using sTfR and ferritin values. Anemia prevalence increased from trimesters 1 and 2 (3-5%, <28 wk) to trimester 3 (25%, 33.2 ± 3.7 wk, P < 0.0001). The prevalence of iron deficiency (sTfR > 8.5 mg/L) doubled from pregnancy to delivery (7% to 14%, P = 0.04). Ferritin and hepcidin concentrations at delivery may have been elevated as a consequence of inflammation because IL-6 concentrations at delivery were 1.6-fold higher than those obtained at 26.1 ± 3.3 wk of gestation (P < 0.0001), and a positive association was found between IL-6 and both hepcidin and ferritin at delivery (P < 0.01). EPO was consistently correlated with hemoglobin (r = -0.36 and -0.43, P < 0.001), ferritin (r = -0.37 and -0.32, P < 0.0001), sTfR (r = 0.35 and 0.25, P < 0.001), TBI (r = -0.44 and -0.37, P < 0.0001), and serum iron (r = -0.22 and -0.16, P < 0.05) at mid-gestation and at delivery, respectively. EPO alone explained the largest proportion of variance in hemoglobin at 26.0 ± 3.3 wk of gestation (R(2) = 0.13, P = 0.0001, n = 113) and at delivery (R(2) = 0.19, P < 0.0001, n = 192). Pregnant adolescents are at high risk of anemia. EPO is a sensitive indicator of iron status across gestation, is not affected by systemic inflammation, and may better predict risk of anemia at term. The trial was registered at clinicaltrials.gov as NCT01019902.

A pilot study on peak systolic velocity monitoring of fetal anemia after administration of chemotherapy during pregnancy

OBJECTIVES

To monitor fetal anemia during administration of chemotherapy to the fetus's mother.

STUDY DESIGN

Between 2007 and 2012 six patients with malignancy diagnosed during pregnancy were included in our prospective study. For evaluation of fetal anemia, peak systolic velocimetry (PSV) of the middle cerebral artery is considered the best method. The patients were repeatedly examined one day before and on the third day after the administration of chemotherapy. At least three measurements were performed and the highest value was used as appropriate. Multiples of the median (MoM) were calculated using the website http://www.perinatology.com/calculators/MCA.htm. When the MoM reached 1.29, moderate anemia was diagnosed.

RESULTS

The women's average age was 30 years. The average gestational age at diagnosis was 20.7 weeks of pregnancy. Borderline fetal anemia was detected in only in one patient. After delivery newborns were examined by standard pediatric evaluation and blood count was provided. There was no evidence of any newborn anemia.

CONCLUSIONS

Chemotherapy administered during pregnancy is becoming more frequent due to increasing knowledge and data on such cases. Close monitoring of the fetus should be performed in specialized centers. For detection of chemotherapy-induced anemia, PSV measurement should be employed.