Hematological Profiles of Preterm Infants and the Impact of Antenatal Steroids

Hematological Profiles of Preterm Infants: Can it be Effected by Antenatal Steroids?

The goal of this observational study is to investigate the impact of antenatal corticosteroids (ANS) administration on haematological parameters in premature infants born to women exposed to ANS.

The primary objective is to assess whether ANS administration in pregnant women during pregnancy alters haematological parameters in preterm neonates; The secondary objectives are: (1) to evaluate changes in haematological parameters in preterm infants in relation to the time interval between ANS administration and delivery, and (2) to assess alterations in haematological parameters according to different maternal ANS dosage regimens.

A total of 524 mother-infant pairs were included in the study. Participants were allocated into six groups based on the time interval between antenatal corticosteroid administration and delivery.

Study Overview

• Status: Completed
• Conditions: Haematology
• Intervention / Treatment: Drug: Antenatal Corticosteroid Exposure; Drug: Antenatal corticosteroids

Detailed Description

Antenatal corticosteroids (ANS) have been widely used since 1972, when Liggins and Howie first demonstrated their beneficial effects on neonatal outcomes. Over time, the recognized benefits of ANS have extended beyond neonatal respiratory support in preterm infants. Current international guidelines recommend administering ANS to pregnant women at risk of imminent preterm delivery before 34 weeks of gestation. ANS therapy has been shown to reduce both morbidity and mortality among preterm neonates.

Glucocorticoid exposure promotes the maturation of multiple fetal organ systems, with a primary emphasis on accelerating lung development and reducing the risk of respiratory distress syndrome (RDS). The optimal therapeutic effect of ANS is observed within a window of 24 hours to 7 days following administration.

However, the potential adverse effects of corticosteroid therapy should not be overlooked and warrant careful consideration. First, corticosteroids may have negative effects on the developing brain, potentially leading to psychosomatic and neurodevelopmental disturbances, owing to the high density of glucocorticoid receptors in brain regions involved in behavioral regulation and endocrine control. Second, several studies have suggested that ANS may increase the risk of neonatal hypoglycemia and disrupt thyroid hormone homeostasis.

In addition, a study conducted by Romejko et al. demonstrated that ANS administration is associated with alterations in hematological parameters among women exposed to prenatal steroids.

Considering that anemia is a common condition among preterm infants, it is crucial to analyze additional factors that may influence hematological test results and complicate diagnostic evaluation. Therefore, reliable assessment of hematological parameters at birth is particularly important in this population.

The primary objective is to assess whether ANS administration in pregnant women during pregnancy alters haematological parameters in preterm neonates.

The secondary objectives are: (1) to evaluate changes in haematological parameters in preterm infants in relation to the time interval between ANS administration and delivery, and (2) to assess alterations in haematological parameters according to different maternal ANS dosage regimens.

• Study Type: Observational
• Enrollment (Actual): 1048

Contacts and Locations

Study Locations

• Poland
  • Warsaw, Poland, 00-315
    • Department of Obstetrics and Gynecology, Warsaw, Medical University of Warsaw, Poland
  • Warsaw
    • Warsaw, Warsaw, Poland, 00-315
      • Department of Obstetrics and Gynecology, Department of Neonatology and Neonatal Intensive Care, Warsaw, Medical University of Warsaw, Poland

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child
• Accepts Healthy Volunteers: No

• Sampling Method: Probability Sample

Study Population

We planned to recruit all consecutive pairs: pregnant women and their preterm infants admitted >24 and ≤ 36 weeks of gestation.

Description

Inclusion Criteria:

• gestational age 24 weeks - <36 weeks

Exclusion Criteria:

• gestational age <24 and⩾36
• major congenital or chromosomal abnormalities
• intrauterine foetal demise
• women with active or suspected cancer
• women underwent surgery or chemotherapy during pregnancy
• women whose pregnancy was prematurely terminated due to maternal indications
• women who received ANS outside of our hospital
• lack of parental consent.

Study Plan

How is the study designed?

Number of groups / cohorts

6

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
1.Optimal window (24hours-7days) group; Pregnant women who delivered 24 hours to 7 days after the last dose of antenatal steroids.	Drug: Antenatal Corticosteroid Exposure; Administration of ANS to pregnant women at risk of preterm delivery, according to standard clinical practice and existing obstetric guidelines. Corticosteroids were administered for fetal lung maturation. Exposure was categorized based on the interval between corticosteroid administration and delivery (24 hours to 7 days, less than 24 hours, more than 7 days), completeness of dosing (one dose only), or absence of exposure due to insufficient time before delivery or lack of clinical indication. This was an observational, exposure-based intervention.; Drug: Antenatal corticosteroids
2.Out-of-window (>7days) group; Pregnant women who delivered more than 7 days after antenatal steroid administration.	Drug: Antenatal Corticosteroid Exposure; Administration of ANS to pregnant women at risk of preterm delivery, according to standard clinical practice and existing obstetric guidelines. Corticosteroids were administered for fetal lung maturation. Exposure was categorized based on the interval between corticosteroid administration and delivery (24 hours to 7 days, less than 24 hours, more than 7 days), completeness of dosing (one dose only), or absence of exposure due to insufficient time before delivery or lack of clinical indication. This was an observational, exposure-based intervention.; Drug: Antenatal corticosteroids
3.Suboptimal (<24 hours) group; Pregnant women who delivered less than 24 hours after antenatal steroid administration.	Drug: Antenatal Corticosteroid Exposure; Administration of ANS to pregnant women at risk of preterm delivery, according to standard clinical practice and existing obstetric guidelines. Corticosteroids were administered for fetal lung maturation. Exposure was categorized based on the interval between corticosteroid administration and delivery (24 hours to 7 days, less than 24 hours, more than 7 days), completeness of dosing (one dose only), or absence of exposure due to insufficient time before delivery or lack of clinical indication. This was an observational, exposure-based intervention.; Drug: Antenatal corticosteroids
4.One-dose group; Pregnant women who received only the first dose of antenatal steroids before delivery.	Drug: Antenatal Corticosteroid Exposure; Administration of ANS to pregnant women at risk of preterm delivery, according to standard clinical practice and existing obstetric guidelines. Corticosteroids were administered for fetal lung maturation. Exposure was categorized based on the interval between corticosteroid administration and delivery (24 hours to 7 days, less than 24 hours, more than 7 days), completeness of dosing (one dose only), or absence of exposure due to insufficient time before delivery or lack of clinical indication. This was an observational, exposure-based intervention.; Drug: Antenatal corticosteroids
5.No steroids - lack of time; Pregnant women who did not receive antenatal steroids due to insufficient time before delivery.
6.No steroids - no recommendation; Pregnant women who did not receive antenatal steroids because therapy was not recommended.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Hemoglobin concentration [g/dl] in preterm infants <36 weeks of gestational age, measured in the first 24 hours of life	Blood samples obtained within the first 24 hours of life; measured parameters will be compared between groups stratified by maternal ANS dosing regimen and interval between corticosteroid administration and delivery.	the first 24 hours of life
Hematocrit level [%] in preterm infants <36 weeks of gestational age, measured within the first 24 hours of life.	Blood samples obtained within the first 24 hours of life; measured parameters will be compared between groups stratified by maternal ANS dosing regimen and interval between corticosteroid administration and delivery.	the first 24 hours of life
Red blood cell count (×10⁶/µL) in preterm infants <36 weeks of gestational age, measured within the first 24 hours of life.	Blood samples obtained within the first 24 hours of life; measured parameters will be compared between groups stratified by maternal ANS dosing regimen and interval between corticosteroid administration and delivery.	the first 24 hours of life

Collaborators and Investigators

• Sponsor: Princess Anna Mazowiecka Hospital, Warsaw, Poland
• Investigators: Study Chair: Ewa Romejko-Wolniewicz, Prof., M.D., Department of Obstetrics and Gynecology, Medical University of Warsaw, Poland

Publications and helpful links

General Publications

• Hasanbegovic E, Cengic N, Hasanbegovic S, Heljic J, Lutolli I, Begic E. Evaluation and Treatment of Anemia in Premature Infants. Med Arch. 2016 Dec;70(6):408-412. doi: 10.5455/medarh.2016.70.408-412.
• Romejko-Wolniewicz E, Oleszczuk L, Zareba-Szczudlik J, Czajkowski K. Dosage regimen of antenatal steroids prior to preterm delivery and effects on maternal and neonatal outcomes. J Matern Fetal Neonatal Med. 2013 Feb;26(3):237-41. doi: 10.3109/14767058.2012.733758. Epub 2012 Oct 18.
• Daskalakis G, Pergialiotis V, Domellof M, Ehrhardt H, Di Renzo GC, Koc E, Malamitsi-Puchner A, Kacerovsky M, Modi N, Shennan A, Ayres-de-Campos D, Gliozheni E, Rull K, Braun T, Beke A, Kosinska-Kaczynska K, Areia AL, Vladareanu S, Srsen TP, Schmitz T, Jacobsson B. European guidelines on perinatal care: corticosteroids for women at risk of preterm birth. J Matern Fetal Neonatal Med. 2023 Dec;36(1):2160628. doi: 10.1080/14767058.2022.2160628.
• Battarbee AN, Ros ST, Esplin MS, Biggio J, Bukowski R, Parry S, Zhang H, Huang H, Andrews W, Saade G, Sadovsky Y, Reddy UM, Varner MW, Manuck TA; Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Genomics and Proteomics Network for Preterm Birth Research (GPN-PBR). Optimal timing of antenatal corticosteroid administration and preterm neonatal and early childhood outcomes. Am J Obstet Gynecol MFM. 2020 Feb;2(1):100077. doi: 10.1016/j.ajogmf.2019.100077. Epub 2019 Dec 17.

Study record dates

Study Major Dates

• Study Start (Actual): January 2, 2011
• Primary Completion (Actual): December 30, 2013
• Study Completion (Actual): December 30, 2013

Study Registration Dates

• First Submitted: November 27, 2025
• First Submitted That Met QC Criteria: January 15, 2026
• First Posted (Actual): January 22, 2026

Study Record Updates

• Last Update Posted (Actual): January 22, 2026
• Last Update Submitted That Met QC Criteria: January 15, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: pregnancy; preterm infant; haematological values; antenatal steroids
• Additional Relevant MeSH Terms: Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Obstetric Labor, Premature; Obstetric Labor Complications; Pregnancy Complications; Premature Birth
• Other Study ID Numbers: ANS-HemProfiles

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: All of the individual participant data collected during the trial will be available. The study protocol will also be available.
• IPD Sharing Time Frame: november 2025-April 2026
• IPD Sharing Access Criteria: documents will be accessible to anyone who provides proposal following publication.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No