(2024) 24:526
Gad et al. BMC Pediatrics
https://doi.org/10.1186/s12887-024-04980-z

BMC Pediatrics

RESEARCH

Open Access

Associations between maternal bacteremia
during the peripartum period and early‑onset
neonatal sepsis: a retrospective cohort study
Ashraf Gad1,2*, Mahmoud Alkhdr1, Rayan Terkawi3, Hafsa Alsharif4, Marwa Ibrahim4, Rasha Amin4,
Elmunzir Algibali4, Prem Chandra5, Manal Hamed6, Hawabibee Mahir Petkar6 and Mohammad A. A. Bayoumi1

Abstract
Introduction Early-onset neonatal sepsis (EONS) significantly impacts neonatal morbidity and mortality, with maternal bacteremia during the peripartum period being a potential risk factor. This study aims to explore the association
between peripartum maternal bacteremia and EONS.
Methods A retrospective cohort study at the Women’s Wellness and Research Center in Doha, Qatar (2015–2019)
compared women with and without bacteremia, based on blood cultures taken from up to seven days before to 48 h
after delivery, examining the association with EONS.
Results Among the 536 maternal blood cultures analyzed, 102 (19.0%) were positive. The most prevalent organisms were Group B streptococcus (GBS) (39.2%), followed by Escherichia coli (14.7%) and anaerobes (10.8%). Neonatesfrom bacteremic mothers had lower birth weights (2913 ± 86 g vs. 3140 ± 745 g; MD 227.63 g; 95% CI 61.72 − 393.55;
p = 0.007), required more resuscitation (27.5% vs. 13.2%; OR 2.48; 95% CI 1.48 − 4.17; p < 0.001), and received antibiotics
for ≥ 7 days more frequently (41.2% vs. 16.6%; OR 3.51; 95% CI 2.20 − 5.62; p < 0.001) compared to those from nonbacteremic mothers. Maternal Gram-positive (GP) organisms were more commonly isolated in term gestation (67.9%)
compared to Gram-negative (GN) (22.2%) and anaerobic bacteremias (9.9%). During intrapartum, GP bacteremia
was predominant (67.1%) vs. GN (21.4%) and Anaerobes (11.4%), with GN bacteremia being more common in postpartum samples. Culture-proven EONS occurred in 0.75% of the cohort, affecting 3.9% of infants from bacteremic
mothers vs. none in controls (OR 2.34; 95% CI 1.27 − 4.31; p < 0.001). Culture-negative EONS appeared in 14.7%
of infants from bacteremic mothers vs. 7.8% in controls (OR 2.02; 95% CI, 1.05 − 3.88; p = 0.03). Among 40 casesof maternal GBS bacteremia, culture-proven GBS EONS occurred in 3 neonates (7.5%), all from mothers with negative
GBS screening, compared to none in the control group. A strong association was found between EONS and maternal
bacteremia due to any organism (aOR 2.34; 95% CI, 1.24 − 4.41; p = 0.009), GP bacteremia (aOR 3.66; 95% CI, 1.82 − 7.34;
p < 0.001), or GBS (aOR 5.74; 95% CI, 2.57 − 12.81; p < 0.001). Bacteremia due to GN and Anaerobic organisms were
not associated with EONS. Chorioamnionitis and antepartum fever were independent predictors for EONS associatedwith significant bacterial isolates.
Conclusion This study underscores the significant impact of maternal GP bacteremia, particularly from GBS,
on EONS. The strong association highlights the need for vigilant monitoring and interventions in pregnancies complicated by bacteremia to reduce adverse neonatal outcomes.
*Correspondence:
Ashraf Gad
agad2@hamad.qa
Full list of author information is available at the end of the article© The Author(s) 2024. Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0
International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as longas you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if
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Gad et al. BMC Pediatrics(2024) 24:526

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Keywords Neonatal sepsis, Newborn, Sepsis, Neonatal bacteremia, Maternal bacteremia, Chorioamnionitis,
Pregnancy, Infection

Introduction
Early onset neonatal sepsis (EONS) is a serious andpotentially life-threatening condition that can cause morbidity and mortality in neonates [1–5]. The incidenceof EONS ranges from 1 to 5 cases per 1,000 live births,
with the most common causative agents being group B
Streptococcus (GBS), Escherichia coli (E.coli) and otherGram-negative (GN) bacteria [6, 7]. Maternal bacteremia during the peripartum period is considered a significant risk factor for EONS [8, 9]. While improvements inperinatal care and screening have led to a decline in theincidence of maternal bacteremia in recent years, EONS
remains a critical concern for neonatal health [10, 11].
Understanding this association is crucial for developing
effective strategies to prevent and manage EONS.
Studies have shown that neonates born to women withany type of perinatal infection or colonization of the vaginal tract with known pathogens during pregnancy havean increased risk of culture-proven sepsis, which further increases if signs of infection are present in either
the mother or the newborn [12–14]. Identifying bacterial pathogens associated with maternal bacteremia and
EONS can inform the choice of appropriate antibiotic
therapy and improve neonatal outcomes [15]. A recent
study found that neonates born to mothers with bacteremia often have the same organism in the blood when
admitted to the NICU for sepsis evaluation. Therefore,
timely detection and treatment of such mothers canimprove fetal and neonatal outcomes [16].
This study aims to fill this knowledge gap by examining
EONS cases linked to positive maternal blood cultures
over five years, providing insights that could enhance theprevention and management of EONS.
Methods
Study setting and period

This retrospective study was conducted over five years,
from 1st January 2015 to 31st December 2019, on
women and their neonates born at the Women’s Wellness and Research Center (WWRC) and the former
Women’s Hospital, both part of Hamad Medical Corporation (HMC) in Doha, Qatar. The former Women’s
Hospital was operational until mid-2018, after which
all maternity facilities moved to the WWRC. The study
was approved by the WWRC Medical Research Center
under protocol number MRC-01–21-427. During thestudy period, 82,860 deliveries occurred, establishing

this centre as one of Qatar’s largest tertiary care facilities. All mothers delivering babies of any GA were
included. Throughout the study period, women meeting national guidelines (based on universal screening of
all pregnant women) for Group B Streptococcus (GBS)
prophylaxis received intrapartum antibiotic prophylaxis [17]. Also, we routinely obtain blood culturesfrom neonates whose mothers have bacteremia or aresuspected to have sepsis. However, the decision to initiate antibiotic therapy varies among physicians.
Microbiology data collection

We retrospectively searched the Microbiology laboratory information management system (LIMS) to identify all women from our maternity facilities who had
blood cultures taken during the study period. Information on positive blood cultures, including organisms
isolated, their significance and the antimicrobial susceptibility patterns were then extracted from the LIMS.
We evaluated 1,212 women presenting to labour anddelivery, who had blood cultures drawn for sepsis evaluation in the labour and delivery (Fig. 1).
Inclusion and exclusion criteria

Pregnant and postpartum women were included in
the study if they had blood cultures taken from 7 days
before to 48 h after delivery, respectively. The timingof maternal blood cultures was categorized as antepartum (1–7 days before delivery), intrapartum (day ofdelivery), or early postpartum (up to 48 h after delivery). The clinical indications for drawing blood culturesencompassed fever (temperature ≥ 38.0 °C (100.4°F),
signs of chorioamnionitis (maternal fever, maternaltachycardia (heart rate > 100 bpm), or fetal tachycardia (heart rate > 160 bpm for 10 min or longer), elevated C-reactive protein (CRP) or white blood (WBC)counts, premature rupture of membranes (PROM) or
preterm labour which might suggest intra-amniotic
infection, fetal death, and additional clinical signs ofsepsis as identified by attending obstetricians. Exclusions involved 676 women with cultures taken outside
the 7-day antepartum to the 48-h postpartum window (n = 643), contaminated culture results (n = 28),
and 5 women with neonates suspected of congenital
anomalies.

Gad et al. BMC Pediatrics(2024) 24:526

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Fig. 1 Flow diagram of inclusion criteria, and bacteremia status

Definitions

Mothers with positive blood cultures drawn from up toseven days before to 48 h after delivery were defined asbacteremic (cases), while those with negative cultures
were referred to as non-bacteremic (control). Neonatal
bacteremia was referred only to those neonates with significantly positive blood cultures in the first three days oflife and excluded contaminated cultures. EONS is identified by either a positive blood or cerebrospinal fluid(CSF) culture obtained in the first three days of age followed by a minimum of seven days of antibiotic therapy
or in cases of culture-negative sepsis, by elevated CRP
levels ≥ 45 mg/L [18, 19] within 72 h coupled with one ormore signs of infection; these signs include unexplained
respiratory support needs, lethargy or feeding difficulties,
infections such as meningitis (defined as a positive CSF
culture or, in the case of culture-negative meningitis, as
any of the following: a corrected WBC count > 26 cells/µL for preterm infants or > 23 cells/µL for term infants,
and a corrected CSF protein level > 150 mg/dL for preterm infants or > 118 mg/dL for term infants), pneumonia, cellulitis, or conjunctivitis, a SNAPPE II score > 20,
unexplained low platelet count (< 100 × ­103/µL), absolute
neutrophil count (ANC) < 1500/µL, or any other symptoms deemed by the neonatologist to be indicative ofsepsis, also requiring a minimum seven-day course ofantibiotics.
Blood culture contamination was defined as the isolation of an organism commonly associated with contamination, e.g., Coagulase-negative Staphylococcus,

diphtheroids, Propionibacterium acnes and reported
as a contaminant by the laboratory based onclinical correlation undertaken by a consultant
Microbiologist.
Significant positive blood culture was defined as theisolation of a pathogen from the blood, reported by thelaboratory based on clinical correlation undertaken bya consultant Microbiologist. The following organisms
were always considered significant: GBS, E.coli, Klebsiellapneumoniae, Streptococcus pyogenes, Staphylococcus
aureus, Haemophilus influenzae, Listeria monocytogenes,
Streptococcus gallolyticus, Streptococcus canis, Streptococcus anginosus, Streptococcus dysgalactiae and Enterococcus faecalis. Anaerobes were considered significant
in the context of chorioamnionitis. For the other organisms, they were considered pathogens or likely pathogens
where the patient had signs of sepsis and the same organism was isolated from another site e.g. high vaginal swab,
placenta, urine or the patient had signs of sepsis and noother organism was isolated from any other site.
Clinical data and outcomesWe retrospectively gathered and analyzed extensive clinical data from both maternal and neonatal records, focusing on indicators and outcomes related to infections andsepsis. Obstetric and neonatal data were collected fromthe organization’s electronic patient records. Maternal
data included demographics, maternal blood timing andresults, anaesthesia, mode of delivery, duration of ruptureof membranes, presence of chorioamnionitis, maternal

Gad et al. BMC Pediatrics(2024) 24:526

WBC count, CRP levels, temperature, GBS status, andpregnancy outcomes at birth (miscarriage, stillbirth,preterm or term delivery). Neonatal data were collectedfrom birth and included NICU admission, WBC counts,
CRP levels, antibiotic treatment duration, as well as clinical data such as high or low temperature, need for respiratory support, activity, feeding problems, presenceof other infections such as meningitis, pneumonia, andScore for Neonatal Acute Physiology and SNAP Perinatal
Extension (SNAPPE II score).
Blood was cultured using the BD BACTEC™ FX (Beckton Dickinson, Franklin Lakes, U.S.A) blood culture
system. Positive bottles were subcultured onto blood(aerobic and anaerobic), chocolate and MacConkey
agar plates. Blood and chocolate agar plates were incubated at 35–37 °C in 5–10% CO2 for 24- 48 h, anaerobic blood agar plates were incubated at 35–37 °C in ananaerobic cabinet for 48 h, and MacConkey agar plates
were incubated at 35–37 °C in the air for 24 h. Identification and susceptibility testing were performed using the
BD Phoenix™ automated identification and susceptibility
testing system (Beckton Dickinson, Franklin Lakes, New
Jersey, U.S.A). For fastidious organisms, identification
was done using the matrix-assisted laser desorption/ionisation-time of flight (MALDI-TOF) mass spectrometry(Bruker, Billerica, Massachusetts, U.S.A), with manualsusceptibility testing by ETEST® (bioMérieux, Marcyl’Étoile, France) to determine minimum inhibitory
concentrations against the antibiotic. Testing and interpretation were done using the Clinical and Laboratory
Standards Institute (CLSI) document [20]. PerformanceStandards for Antimicrobial Susceptibility Testing (themost current edition when the isolate was tested).
Laboratory methods

Statistical analysis

In our statistical analysis, we focused on comparing
two distinct cohorts: pregnant and postpartum womenwith bacteremia, serving as the case group, and a control group comprising women without bacteremia. We
conducted descriptive analyses to examine the dataset,assessing inter-group differences using Fisher’s exact
test or the Chi-square test for categorical variables andthe t-test for continuous variables. Categorical variables
were depicted as percentages, with their relationships
expressed in terms of odds ratios, whereas continuous
variables were summarized by means and standard deviations, along with mean differences. Univariate logistic
regression was utilized to investigate the relationships
between various exposures and EONS. Multivariate
regression was then applied to adjust for potential confounders and to identify organism groups associatedPage 4 of 13

with EONS. Statistical significance was determined at a
two-tailed p-value < 0.05. All statistical procedures wereconducted using SPSS for Windows (version 29.0, IBM
Corp., Armonk, NY, USA).

Results
We identified 1,212 pregnant women with significant
positive blood cultures who visited the labour and delivery wards during the study period. Blood cultures werecollected outside the peripartum window in 643 cases.
Twenty-eight blood cultures were identified as contaminants, the majority of which were coagulase-negative
Staphylococci, as well as two cases of Bacillus species.
Additionally, five neonates were excluded for congenital
anomalies. Following the application of exclusion criteria, 102 women (19%) with bacteremia matched with acontrol group of 434 women (81%) were included in ourstudy. Figure 1 represents the study design flowchart.
Table 1 presents demographic, clinical, and obstetric characteristics associated with maternal peripartum
bacteremia. Women with bacteremia were found to beslightly older with an average age of 32.2 years comparedto 31 years in the non-bacteremic group, mean difference(MD) 1.24; (95% Confidence interval (CI), 0.07 to 2.42;
p = 0.04), and exhibited a higher incidence of postpartum
fever (17% vs. 6.0%, Odds Ratio (OR), 3.19; 95% CI, 1.66
to 6.16; p < 0.001). They also showed elevated CRP values before/during labour (53.7 ± 53.9 vs. 38.9 ± 33.6 mg/
dl; MD, 14.83; 95% CI, 4.01 to 25.64; p = 0.01) and postdelivery (146.5 ± 113 vs. 82.2 ± 73 mg/dl, MD, 64.21;
95% CI, 40.11 to 88.31; p < 0.001). Moreover, bacteremic
mothers were less likely to receive epidural analgesia(60.4% compared with 74.4%; OR, 0.52; 95% CI, 0.33 to
0.82; p = 0.01). Additionally, the incidence of PROM waslower in the bacteremic group (17.3% vs. 27.3%, OR, 0.56;
95% CI, 0.31 to 0.99; p = 0.04). The majority of maternal blood cultures (79.9%) were collected during labour,while the rest were obtained from antepartum (12.8%)
and postpartum (7.3%), highlighting the critical periodof labour for the occurrence of bacteremia in the studied
population.
Table 2 presents a detailed comparison of neonatal demographics and clinical variables associated withmaternal peripartum bacteremia. Neonates of bacteremic mothers had a higher incidence of low birth weight(LBW) (BW < 2500 g) (19.6% vs. 11.1%; OR: 1.96, 95% CI:
1.10 to 3.48, p = 0.02) and preterm birth (19.8% vs. 11.4%;
OR: 1.92, 95% CI: 1.08 to 3.41, p = 0.02). The averagebirth weight was 2913 g compared to 3140 g in neonatesborn to mothers without bacteremia (MD: -227.63, 95%
CI: -393.55 to -61.72, p = 0.007). They also had higher
rates of Apgar scores < 7 at 1 and 5 min (OR: 1.97, p = 0.04
and OR: 1.61, p = 0.002, respectively) and a greater need

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Table 1 Demographic, clinical, and obstetric profiles of pregnant and puerperal women: a comparison between cases withbacteremia and controls without bacteremia
Controls(N = 434)

Cases(N = 102)

Mean Difference/
Odds Ratio (95% CI)p

31 ± 5.25

32.2 ± 6.1

1.24a [0.07 to 2.42]

0.04

74 (17.1%)

19 (18.6%)

1.09 [0.61 to 1.94]

0.76

Antepartum

37 (8.6%)

14 (13.7%)

1.69 [0.88 to 3.27]

0.11

Intrapartum

255 (58.8%)

63 (61.8%)

1.13 [0.72 to 1.76]

0.56

Postpartum

26 (6.0%)

17 (17.0%)

3.19 [1.66 to 6.16]< 0.001

Epidural analgesia, N (%)

320 (74.4%)

61 (60.4%)

0.52 [0.33 to 0.82]

0.01

PROM, N (%)

112 (27.2%)

17 (17.3%)

0.56 [0.31 to 0.99]

0.04

Chorioamnionitis, N (%)

322 (84.7%)

77(78.6%)

0.66 [0.37 to 1.15]

0.14

Vaginal delivery, N (%)

176 (40.6%)

48 (47.1%)

1.30 [0.84 to 2.01]

0.23

Peripartum highest WBC (103 /uL), Mean ± SD

18.3 ± 6.3

19.3 ± 6.9

0.97a [-0.40 to 2.36]

0.17

Antepartum/Intrapartum highest CRP (mg/L), Mean ± SD

38.9 ± 33.6

53.7 ± 53.9

14.83a [4.01 to 25.64]

0.01

Postpartum highest CRP (mg/L), Mean ± SD

82.2 ± 73

146.5 ± 113

64.2a [40.11 to 88.31]< 0.001

Antepartum

56 (12.9%)

13 (12.7%)

0.98 [0.51 to 1.88]

0.96

Intrapartum

358 (82.5%)

70 (68.6%)

0.46 [0.28 to 0.75]

0.002

Postpartum

20 (4.6%)

19 (18.6%)

4.73 [2.42 to 9.26]< 0.001

Maternal age (years), Mean ± SDb

Positive GBS status , N (%)
Maternal fever, N (%)

Timing of blood culture, N (%)

Data are presented as n (%) or mean ± standard deviation unless otherwise indicated. Statistical significance is defined as p values < 0.05. P values are determinedusing a two-sample t-test
Missing values: Anesthesia (n = 5), Chorioamnionitis (n = 58); PROM (n = 14); peripartum CRP (n = 194); postpartum CRP (n = 277)
GBS Group B Streptococci, PROM premature rupture of membranes, WBC white blood count, CRP C-reactive protein. Data are presented as n (%) or mean ± standard
deviation, unless otherwise specified. Statistical significance defined as P < 0.05
aMean differenceb

Among all patients, including 117 cases with unknown GBS status

for resuscitation at birth (27.5% vs. 13.2%; OR: 2.48, 95%
CI: 1.48 to 4.17, p < 0.001). Moreover, they had higher
SNAPPE II scores (7.87 vs. 2.94; MD: 4.93, 95% CI: 2.94
to 6.92, p < 0.001) and a marginal increase in the needfor respiratory support in the NICU (34.7% vs. 25.1%;
OR: 1.58, 95% CI: 0.98 to 2.53, p = 0.05). Of note, level III
NICU admissions rates were lower in the neonates of thebacteremic group (65.9% vs. 82.9%; OR: 0.394, 95% CI:
0.243 to 0.637, p < 0.001). However, no significant differences were observed in the rates of stillbirth/miscarriage,
small for gestational age (SGA), multiple gestation, gender, or hypoglycemia symptoms in these neonates.
Figure 2 presents organisms identified positive blood
cultures collected from pregnant and postpartum mothers, with the majority of cases caused by GBS (39.2%),
followed by E.coli (14.6%), and anaerobes (10.8%). In thisstudy, 58.8% of bacteremia cases were due to Gram-positive (GP) organisms, with GBS being the cause in twothirds of those cases, followed by GN organisms at 30.4%,
and anaerobes representing 10.8%. A total of 11 GN isolates identified as extended-spectrum β-lactamase producers (ESBL) included E.coli (8 out of 12, accounting for53.3% of all E.coli cases) and K.pneumoniae (3 out of 7,

accounting for 42.9% of all K.pneumoniae cases). Amongthe maternal cases of ESBL producers, two neonates born
to women with ESBL-producing E.coli developed culture-negative sepsis and received treatment for ten days.
In three cases, GBS was isolated from both maternal
and neonatal blood cultures, with one case only demonstrating GBS infection in the placental tissue. However, overall analysis revealed no significant correlation
between the organisms identified in maternal placental
cultures and those found in neonatal blood cultures.
Significant differences were observed in the gestational
distribution and timing of bacteremias about the typeof isolate groups (GP, GN, and anaerobes) among peripartum women. Maternal GP bacteremia was prevalent
in cases with normal BW (≥ 2500 g) and term gestation(≥ 37 weeks), accounting for 67.9% of all cases, compared
to 22.2% for GN bacteremia and 9.9% for anaerobic infections. Conversely, maternal GN bacteremia was moreprevalent in low LBW and preterm gestation (61.9%)of all cases, compared to 23.8% for GP bacteremia and14.3% for anaerobic infections.
During the intrapartum period, maternal blood cultures were predominantly GP organisms, (67.1%). In

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Table 2 Demographic and clinical profiles of neonates from bacteremic (Cases) and non-bacteremic (Control) pregnant andpuerperal womenControls(N = 434)

Cases(N = 102)

Mean Difference/
Odds Ratio (95% CI)

p

GA (weeks), Mean ± SD

38.2 ± 3.84

37.4 ± 4.41

-0.82a [-1.67 to 0.02]

0.06

Preterm, N (%)

48 (11.4%)

20 (19.8%)

1.92 [1.08 to 3.41]

0.02

Term, N (%)

374 (88.4%)

81 (80.2%)

0.53 [0.29 to 0.49]

0.03

Stillborn, N (%)

12 (2.8%)1(1%)

0.34 [0.04 to 2.70]

0.29

BW (grams), Mean ± SD

3140 ± 745

2913 ± 860-227.63a [-393.55 to –61.72]

0.007

LBW (groups), N (%)

48 (11.1%)

20 (19.6%)

1.96 [1.10 to 3.48]

0.02

SGA, N (%)

34 (7.8%)

12 (11.8%)

1.56 [0.78 to 3.14]

0.20

Multiple gestation, N (%)

12 (2.8%)

4 (3.9%)1.43 [0.45 to 4.54]

0.54

Female, N (%)

206 (48.1%)

53 (52%)

1.16 [0.75 to 1.79]

0.49

Apgar scores (< 7), N (%)
Apgar 1 min

32 (8.0%)

15 (14.7%)

1.97 [1.02 to 3.80]

0.04

Apgar 5 min

4 (1%)

6 (5.9%)6.15 [1.70 to 22.24]

0.002

SNAPPE II, Mean ± SD

2.94 ± 6.59

7.87 ± 16.17

4.93a [2.94 to 6.92]< 0.001

DR resuscitation, N (%)

56 (13.2%)

28 (27.5%)

2.48 [1.48 to 4.17]< 0.001

NICU admission, N (%)

350 (82.9%)

67 (65.7%)

0.39 [0.24 to 0.63]< 0.001

Respiratory support, N (%)

106 (25.1%)

34 (34.7%)

1.58 [0.98 to 2.53]

0.05

Hypoglycemia 24 h, N (%)

82 (19.4%)

26 (25.7%)

1.43 [0.86 to 2.38]

0.16

Data are presented as n (%) or mean ± standard deviation unless otherwise indicated. Statistical significance is defined as p values < 0.05. P values are determinedusing a two-sample t-test
Missing values: APGAR scores (n = 36); Delivery Room Resuscitation (n = 10); NICU admission (n = 12); Respiratory Support (n = 16); Hypoglycemia (n = 13)
GA Gestational Age, Preterm less than 37 weeks’ gestation, BW Birth Weight, LBW Low Birth Weight (< 2500 g), SGA, Small for Gestational Age, SNAPPE II Score for
Neonatal Acute Physiology and SNAP Perinatal Extension, DR Delivery Room, NICU Neonatal Intensive Care Unita

Mean difference

Fig. 2 *Prevotella bivia (3); Prevotella disiens (1); Prevotella species (1); Veillonella montpellierensis (1); Atopobium vaginae (1); Atopobium species (1);unidentified Gram-negative anaerobic bacillus (1); Peptoniphilus harei (1); Peptoniphilus lacrimalis (1). #Oligella urethralis (1); Moraxella species (1);
Leclercia adecarboxylata (1); Chryseobacterium species (1); Pantoea agglomerans (1); Gardnerella vaginalis (1); Listeria monocytogenes (1); Granulicatella
elegans (1); Enterococcus faecalis (1); Aerococcus species (1); Streptococcus dysgalactiae (1); Streptococcus canis (1)Gad et al. BMC Pediatrics(2024) 24:526

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contrast, GN organisms and anaerobes were less common, representing 21.4% and 11.4% of cultures, respectively, p = 0.01. On the other hand, in the postpartum
period, there was a higher prevalence of GN organisms (57.9%) of positive cultures, while GP organisms
accounted for 36.8%, and anaerobes were relatively rare
at 5.3%, p = 0.01. Additionally, there were no significant
differences in bacterial isolates when maternal cultures
were collected antepartum.
In cases of chorioamnionitis, GP organisms accounted
for 62.3% of the cases, as opposed to GN organisms at
23.4% and anaerobes at 14.3% (p = 0.012). It is noteworthy that all positive anaerobic cultures were associatedwith chorioamnionitis, suggesting a short of significant
association (p = 0.06).
Table 3 presents a detailed comparison of laboratory
and microbiology variables in the neonates of womenwith and without peripartum bacteremia. Neonates bornto bacteremic mothers exhibited elevated CRP levels,with 18.1% having CRP levels ≥ 25–44 mg/L compared to
9.6% in the control group (OR, 2.09; 95% CI, 1.018 − 4.09;
p = 0.03). Moreover, 16.7% of neonates from bacteremic
mothers had CRP levels ≥ 45 mg/L, while only 8.8% in
the control group reached this threshold (OR, 2.08; 95%
CI, 1.12 − 43.87; p = 0.02). The overall highest CRP values
in this group were 24.1 ± 25.5 mg/L, significantly higher

than the control group’s 14.7 ± 20.9 mg/L (MD 9.36; 95%
CI, 4.12 − 14.59; p < 0.001). Additionally, neonates bornto bacteremic mothers had a higher rate of neutropenia(5.9% vs. 1.4%; OR, 4.46; 95% CI, 1.41 − 14.12; p = 0.01).
The overall incidence of culture-proven EONS in theentire cohort is 0.75%, and 9.89% for any EONS, including culture-negative cases. The latter was higher in neonates of bacteremic mothers (18.6% vs. 7.8%; OR, 2.69;
95% CI, 1.46 − 4.95; p = 0.001) than those born to nonbacteremic mothers. Four neonates with culture-proven
EONS were identified in the study groups (three casesof GBS and one case of Acinetobacter baumannii, compared to none in the control group; OR, 2.34; 95% CI,
1.27 − 4.31; p < 0.001). Among 40 cases of maternal GBS
bacteremia, culture-proven EONS occurred in only 3
neonates (7.5%), whereas there were no cases of GBS sepsis in neonates born to the control group (p < 0.001).
The cases of EONS due to GBS occurred in termneonates born to mothers with GBS bacteremia. Thesemothers had negative GBS screening results within
3 weeks before delivery and did not receive GBS antibiotic prophylaxis. In contrast, the case of Acinetobacterbaumannii sepsis occurred in a 2.5 kg neonate who wasborn at home. The mother’s blood culture grew Granulicatella elegans, while the placenta culture revealed
Staphylococcus aureus and Streptococcus anginosus.

Table 3 Laboratory and clinical outcomes of neonatal sepsis and antimicrobial treatment of newborns from bacteremic (Cases) andnon-bacteremic (Control) pregnant and puerperal womenControls(N = 434)

Cases(N = 102)

Mean Difference/
Odds Ratio (95% CI)p
0.96

Platelets (< 100 × 103)b, N (%)

4 (0.9%)1 (1.0%)1.06 [0.11 to 9.26]

ANC < 1500/uLc, N (%)

6 (1.4%)6 (5.9%)4.45 [1.40 to 14.12]

0.01

CRP ≥ 45 mg/Ld, N (%)

38 (8.8%)

17 (16.7%)

2.08 [1.12 to 3.86]

0.02

CRP 25-44 mg/Ld, N (%)

34 (9.6%)

15 (18.1%)

2.08 [1.07 to 4.04]

0.03

CRP (mg/L)d, Mean ± SD

14.7 ± 20.9

24.1 ± 25.5

9.35a [4.12 to 14.59]< 0.001

Meningitise, N (%)

2 (0.5%)2 (2.0%)4.24 [0.59 to 30.46]

0.12

Pneumonia, N (%)

4(0.9%)

2 (2.0%)2.15 [0.38 to 11.90]

0.36

Other infectionf, N (%)

2 (0.5%)0(0.0%)

0.80 [0.77 to 0.84]

0.49

BC collected, N (%)

366 (84.3%)

92 (90.2%)

1.43 [0.86 to 2.38]

0.13

EONS (all cases), N (%)

34 (7.8%)

19 (18.6%)

2.69 [1.46 to 4.95]

0.001

Culture-proven sepsis, N (%)

0 (0.0%)4 (3.9%)0.18 [0.15 to 0.22]< 0.001

Culture-negative sepsis, N (%)

34 (7.8%)

15 (14.7%)

2.02 [1.05 to 3.88]

0.03

Duration of antibiotics, Mean ± SD

3.9 ± 2.9

5.3 ± 4.5

1.77a [1.06 to 2.47]< 0.001

Antibiotics duration (≥ 7 days), N (%)

72 (16.6%)

42 (41.2%)

3.51 [2.20 to 5.62]< 0.001

ANC Absolute Neutrophil Count, CRP C-reactive Protein, BC Blood Culture, EONS Early-Onset Neonatal Sepsis. The data are presented as n (%) or mean ± standard
deviation unless otherwise specified. Statistical significance is defined as p values < 0.05. The P value was determined using a two-sample t-testaMean differenceb

Platelet values missing for the control group (n = 78) and bacteremic group (n = 19)c

ANC values missing for the control group (n = 66) and bacteremic group (n = 13)d

CRP values missing for the control group (n = 65) and bacteremic group (n = 13)eMeningitis values missing for the control group (n = 8) and bacteremic group (n = 0)f

Bacterial Conjunctivitis

Gad et al. BMC Pediatrics(2024) 24:526

Page 8 of 13

A higher percentage of neonates born to bacteremic mothers were on antimicrobials for at least sevendays (41.2% vs. 16.6%, OR, 3.52; 95% CI, 2.20 − 5.62;
p < 0.001). Blood cultures were obtained from 458 neonates in the study, accounting for 85.44% of the total
population. Notably, the subject group had a slightly
higher rate of blood culture collection (90.2% vs. 84.3%)
compared to the control group, although this difference
was not statistically significant (p = 0.13).
Regarding antibiotic treatment duration, neonates inthe subject group received antimicrobials for an average of 5.3 ± 4.5 days, which was significantly longer
than the control group’s average of 3.5 ± 2.9 days (MD1.77; 95% 95% CI, 1.06 − 2.47; p < 0.001). In this study,
four neonates were diagnosed with meningitis, all withnegative CSF cultures. Among them, two cases wereborn to GBS-bacteremic women and were treated witha 21-day course of Penicillin G. Notably, only one neonate developed GBS bacteremia. The remaining two
neonates were born to non-bacteremic mothers; however, placental tissue cultures indicated positive GBS
results. Both of these infants received a 14-day Penicillin G treatment. No deaths were reported, and there

were no significant differences in the rates of congenital
pneumonia or other infections between the two groups.
In Table 4, the clinical characteristics of women whose
neonates developed EONS (n = 53) are compared with
controls whose neonates did not have EONS (n = 483).
Among the timing of fever, antepartum fever was significantly higher in mothers of neonates with EONS
(20.8% vs. 8.3%; OR: 3.88, 95% CI: 1.38 − 6.04, p = 0.003).
Although maternal age was slightly higher in the EONS
group, there was no statistical difference. Additionally, noother differences were found in the rates of GBS status,
maternal CRP and WBC count, PROM, chorioamnionitis, delivery mode, receiving an epidural, and timing ofblood cultures.
Regression analysis was conducted to investigate theassociation of EONS with maternal bacteremia, comparing groups of neonates with EONS (cases) and those without EONS (controls). The analysis aimed to separately
identify maternal bacterial isolates associated with EONS
while adjusting for significant peripartum predictors.
In Table 5, univariate analysis of the outcome EONS
showed positive associations with maternal bacteremia due to any organism, particularly GP organisms. A

Table 4 Demographic and clinical characteristics of women whose neonates have EONS and controls without EONSNo EONS(N = 483)

EONS(N = 53)

Mean Difference/
Odds Ratio (95% CI)

p31.1 ± 5.34

32.4 ± 6.0-1.3a [-2.84 to -0.24]

0.09

81 (21.4%)

12 (30%)1.57 [0.768 to 3.23]

0.21

Antepartum

40 (8.3%)

11 (20.8%)

2.88 [1.38 to 6.04]

0.003

Intrapartum

281 (58.2%)

37 (69.8%)

1.66 [0.90 to 3.07]

0.10

Postpartum

40 (8.4%)

3 (5.7%)0.65 [0.197 to 2.20]

0.49

Epidural analgesia, N (%)

346 (72.4%)

35 (66.0%)

0.74 [0.40 to 1.35]

0.33

PROM, N (%)

112 (24.5%)

17 (32.1%)

1.45 [0.78 to 2.69]

0.23

Chorioamnionitis, N (%)

350 (82.2%)

49 (94.2%)

3.54 [1.077 to 11.679]

0.27

Vaginal delivery, N (%)

205 (42.5%)

19 (35.8%)

0.75 [0.42 to 1.36]

0.35

Peripartum highest WBC (103 /uL), Mean ± SD

18.4 ± 6.2

19.11 ± 7.6

0.64a [-0.24 to 1.17]

0.48

Antepartum/Intrapartum highest CRP (mg/L), Mean ± SD

41.7 ± 38.6

37.9 ± 32.5

3.73a [-9.43 to 16.92]

0.577

Postpartum highest CRP (mg/L), Mean ± SD

96.0 ± 87.8

113.8 ± 96.2

-17.76a [-53.30 to 17.77]

0.32

Antepartum

59 (12.2%)

10 (18.9%)

1.67 [0.79 to 3.50]

0.17

Intrapartum

386 (79.9%)42 (79.2%)

0.95 [0.47 to 1.93]

0.90

Postpartum

38 (7.9%)

1 (1.9%)0.22 [0.03 to 1.67]

0.11

Maternal age (years), Mean ± SDb

Positive GBS status , N (%)
Maternal fever, N (%)

Timing of blood culture, N (%)

Data are presented as n (%) or mean ± standard deviation unless otherwise indicated. Statistical significance is defined as p values < 0.05. P values are determinedusing a two-sample t-test
Missing values: Anesthesia (n = 5), Chorioamnionitis (n = 58); PROM (n = 26); peripartum CRP (n = 194); postpartum CRP (n = 277)
GBS Group B streptococci, PROM premature rupture of membranes, WBC white blood count, CRP C-reactive protein. Data are presented as n (%) or mean ± standard deviation,
unless otherwise specified. Statistical significance = P < 0.05
aMean differencebComputation included 117 cases with unknown GBS status, including 96 in the no EONS group and 21 in the EONS groupGad et al. BMC Pediatrics(2024) 24:526

Page 9 of 13

Table 5 Univariate analysis of key perinatal covariates linked toearly onset neonatal sepsis outcome
Variablesa

EONS (N = 53)

OR [95% CI]

P

0.001

Any maternal bacterial IsolatesYes

19 (18.6)

2.69 [1.465 to 4.95]

No

34 (7.8)

1.0

Maternal bacterial Isolate groups
Gram-positive organisms   Yes16 (26.7)

4.28 [2.18 to 8.37]  No

37 (7.8)

1.0< 0.001

Gram-negative organisms   Yes1 (3.2)0.39 [0.05 to 2.96]  No

34 (7.8)

1.0

0.36

Anaerobic organisms   Yes2 (18.2)

2.61 [0.54 to 12.58]  No

34 (7.8)

1.0

0.23

Maternal bacterial Isolate species
GBS   Yes14 (35.0)

6.33 [3.02 to 13.25]  No

34 (7.8)

1.0< 0.001

Escherichia coli   Yes1 (6.7)0.84 [0.10 to 6.58]  No

34 (7.8)

1.0

0.86

Maternal age, years

32.4 ± 6.0

1.04 [0.99 to 1.09]

0.09

Median (IQR)

31.0 (28.5, 35)
0.009

Other predictors

Peripartum fever   Yes47 (11.9)

3.03 [1.27 to 7.27]  No

6 (4.3)1.0

Antepartum fever   Yes11 (21.6)

2.88 [1.38 to 6.04]  No

42 (8.7)

1.0

0.003

Chorioamnionitis   Yes49 (12.3)

3.54 [1.07 to 11.67]  No

3 (3.8)

1.0

0.03

SGA
   Yes1 (2.2)0.18 [0.02 to 1.38]  No

52 (10.6)

1.0

0.07

Categorical Data Values Are Presented in N (%) And Quantitative Data Values Are
Presented in Mean ± standard Deviation (SD)EONS Early-Onset Neonatal Sepsis, GBS Group B Streptococci, SGA Small for
Gestational Age, aOR Adjusted Odds Ratio, p values < 0.05 considered significant
aVariables Examined for Correlation with EONS In Univariate Analysis andShowed No Significant Correlation (P > 0.1): Maternal Factors Like GBS Status,
Fever Post-Delivery, Timing of Maternal Blood Culture; Epidural Use, PROM,
Delivery Method, Pre- and Post-Delivery CRP Levels, And WBC Count. Neonatal
Factors Lacking Significant Correlation Included Gestational Age, Birth Weight,
Prematurity, Low Birthweight, Gender, 1- And 5-Minute APGAR Scores, Score
for Neonatal Acute Physiology with Perinatal Extension II, And Cases of Multiple
Gestation

significant association was also found with GBS bacteremia alone. No significant associations were found withbacteremia due to GN organisms, E. coli, or Anaerobes.

Other potential predictors of any EONS found in the univariate analyses (p values ≤ 0.10) were chorioamnionitis,
peripartum fever, antepartum fever, maternal age, andSGA. These variables were included in the multivariate
regression presented in Table 5.
The regression analysis for the "Culture-Proven EONS"
model could not be executed due to the absence of GBS
EONS events in neonates of women without bacteremia.
However, as shown earlier, the 2 × 2 factorial design indicated statistical significance. No other maternal bacterial
isolate or peripartum predictors were found to have significant associations with culture-proven EONS. Other
nonsignificant peripartum variables that showed no independent association with EONS (p > 0.10) in the univariate analysis are listed in Table 5 legend.
In Table 6, a forward LR stepwise multivariate analysis
was performed to separately determine which group ofmaternal bacteremia or species is independently associated with EONS while accounting for other significant
predictors in the univariate analysis (maternal age, chorioamnionitis, peripartum fever, antepartum fever, and
SGA). A strong association was found between EONS
and maternal bacteremia with any organisms (adjusted
OR (aOR) 2.34; 95% CI, 1.24 − 4.41; p = 0.009), antepartum fever (aOR 3.67; 95% CI, 1.10 − 12.27; p = 0.03)
and chorioamnionitis (aOR 2.37; 95% CI, 1.11 − 5.07;
p = 0.02). Similarly, maternal GP bacteremia (aOR 3.66;
95% CI, 1.82 − 7.34; p < 0.001) and antepartum fever(aOR 3.05; 95% CI, 1.40 − 6.63; p = 0.005) were associated with any EONS. GN and anaerobic organisms were
not associated with EONS. Lastly, maternal GBS bacteremia strongly correlated with EONS (aOR 5.74; 95%
CI, 2.57 − 12.81; p < 0.001) as did antepartum fever (aOR
3.23; 95% CI, 1.42 − 7.33; p = 0.005), while chorioamnionitis showed a marginal association (aOR 4.27; 95% CI,
0.97 − 18.69; p = 0.054). Other predictor variables likematernal age, peripartum fever, and SGA showed no significant relationship with EONS.

Discussion
The study found that maternal bacteremia significantly
raises the risk of EONS in neonates who received antimicrobials and were admitted to the NICU. As reported by
Wilkie et al., their study found a 6.2% rate of proven sepsis [21]. In contrast, our results demonstrated a 3.9% rateof culture-proven sepsis and an overall incidence rateof 18.6% for EONS among neonates born to bacteremic
mothers.
In our study, we observed a 19% incidence of maternal bacteremia within the entire cohort, which is lower
than the 28.7% incidence reported by Easter et al. for allmaternal cultures taken due to suspected maternal infection [12]. In that study, 89% of neonates who developed

Gad et al. BMC Pediatrics(2024) 24:526

Page 10 of 13

Table 6 Multivariate analysis of key covariates linked to early
onset neonatal sepsis outcome across different bacterial isolates
PredictorsaOR [95% CI]

P

1. Any Maternal Bacterial Isolates
Any organisms  Yes

2.34 [1.24 to 4.41]

  No

1.0

0.009

Antepartum fever  Yes

2.37 [1.11 to 5.07]

  No

1.0

0.02

Chorioamnionitis  Yes

3.67 [1.10 to 12.27]

  No

1.0

0.03

2. Maternal Bacterial Isolate Groups
Gram-positive organisms  Yes

3.66 [1.82 to 7.34]

  No

1.0

< 0.001

Gram-negative organisms  Yes

0.29 [0.04 to 2.31]

  No

1.0

0.24

Anaerobes  Yes

1.78 [0.35 to 9.01]

  No

1.0

0.482

Antepartum fever  Yes

3.05 [1.40 to 6.63]

  No

1.0

0.005

3. Maternal Bacterial Isolate Species
GBS
  Yes

5.74 [2.57 to 12.81]

  No

1.0

< 0.001

Chorioamnionitis  Yes

4.27 [0.97 to 18.69]

  No

1.0

0.054

Antepartum fever  Yes

3.23 [1.42 to 7.33]

  No

1.0

0.005

The reference value for both the predictor (s) and outcome is "No."
Predictor(s) entered were Bacterial Isolate(s) of Interest, Maternal age,
Chorioamnionitis, Peripartum Fever, Antepartum Fever, and SGA
EONS Early-Onset Neonatal Sepsis, GBS Group B Streptococci, SGA Small for
Gestational Age, aOR Adjusted Odds Ratio, p values < 0.05 considered significant

bacteremia had the same organism in their blood as theirmothers, while in our study, this percentage was 75%.
However, Wilkie et al. found that only 35.5% of neonateswith the same type of organism as their mothers within
the first week of life had the same organism [21]. Differences in neonatal and postpartum observation timeframes could account for the lower incidence of sametype bacteremia reported by Wilkie et al. compared tothe other studies.

As indicated by the results, fever, particularly postpartum and elevated levels of CRP were present in womenwith bacteremia, suggesting an infectious cause of thesefindings; additionally, chorioamnionitis was independently associated with EONS in our study. GBS and E.
coli were the most common pathogens causing maternal
bacteremia. Notably, all three neonates who developed
GBS sepsis within three days of delivery had positive
maternal cultures collected intrapartum for the sameorganism. Consistent with published data, GBS is more
likely to be identified in septic neonates born to womenwith bacteremia during the intrapartum period. In comparison, bacteremia caused by GN organisms is more
likely to occur during the antepartum or postpartum
period [14, 21–23]. In contrast, the maternal blood culture of the neonate who developed Acinetobacter sepsis
was drawn on the first postpartum day. Although blood
cultures are usually taken when sepsis is suspected, thetiming of maternal blood culture was not found to be an
overall risk factor for EONS, as indicated by the regression analysis results.
Although we don’t have a long postpartum followup period in our study, above one-third of postpartum
women had GN bacteremia, consistent with the previous studies [21–23]. Our findings suggest that neonatesborn to bacteremic mothers, with lower Apgar scores,
required more resuscitation and more respiratory support at birth; displaying signs of sepsis, as also indicatedby higher CRP values. Furthermore, neonates of womenwith GBS bacteremia are more likely to grow GBS when
admitted to the NICU for sepsis evaluation as suggestedby the regression analysis results.
It’s noteworthy that despite a lower incidence, a significant number of culture-negative EONS cases wereobserved in neonates born to women without bacteremia.
This phenomenon may be attributed to various factors,
such as the effective elimination of bacteria in maternal
blood due to adequate administration of antimicrobials,
inadequate collection of blood culture samples, or thepresence of maternal infections not detectable throughblood cultures, like genitourinary infections or chorioamnionitis. The increased likelihood of blood culture collection for sepsis evaluation in these women during theperipartum period, driven by clinical symptoms like peripartum fever, PROM, and chorioamnionitis, further supports this notion. Such clinical presentations suggest ahigher prevalence of infectious processes or sepsis in thissubgroup, relative to the broader neonatal population [6,7], underscoring the importance of comprehensive evaluations in these scenarios.
Furthermore, in our study, maternal bacteremia wasmore prevalent in LBW and preterm infants, which isconsistent with findings from previous studies [24, 25].

Gad et al. BMC Pediatrics(2024) 24:526

The findings also align with those reported by O’Sullivan
et al., indicating high rates of prematurity and maternal
bacteremia occurring during intrapartum and postpartum periods associated with GBS and E. coli isolates,
respectively [1, 23, 26, 27].
The study highlights the significant impact of bacterial
isolates on the risk of EONS, with any bacterial presence
increasing the odds by approximately 2.6 times [10–14].
Notably, GP bacteria, especially GBS, are identified as
major contributors to EONS, reinforcing their established role in neonatal infections [6, 7, 10, 28, 29].
The occurrence of neonatal GBS sepsis in three neonates, despite their mothers testing negative for GBS
within three weeks before delivery and not receiving
GBS antibiotic prophylaxis, suggests that a negative GBS
screening result does not always accurately predict theabsence of maternal GBS bacteremia at the time of delivery. The lack of prophylaxis in these cases underscores a
critical gap in preventing neonatal GBS sepsis. Potential
explanations could include the transient nature of GBS
colonization or inaccuracies in the screening process.
This highlights the need for re-evaluating screening timing, considering additional or repeated testing closer todelivery, and exploring adjunctive strategies to identify
and manage at-risk pregnancies more effectively to prevent adverse neonatal outcomes [30, 31].
In contrast, GN bacteria were not significantly associated with a higher risk of EONS, possibly due to theirhigher incidence in the postpartum, which might limit
their impact on newborns compared to GP bacteriathat are more likely detected during the antepartum andintrapartum periods. Furthermore, maternal GP sepsis islinked to increased neonatal mortality compared to GN
sepsis, suggesting the severe impact of GP infections [32].
Maternal clinical infection, as indicated by a high incidence of antepartum fever and chorioamnionitis, wasconfirmed to significantly increase the risk of EONS in
our study, consistent with existing literature that underscores its role in neonatal sepsis development [33, 34].
Conversely, being SGA was not significantly associatedwith EONS, aligning with recent findings from a study in
Ethiopia [35].
Interestingly, while all positive Anaerobic cultures inthis study were linked to chorioamnionitis, Anaerobes
were not independently associated with EONS. Thisobservation is in line with previous research indicating
the common involvement of Anaerobes in chorioamnionitis but suggests their indirect role in EONS [36], highlighting the complex interplay of maternal infections andneonatal outcomes.
Finally, the management of infants born to mothers with bacteremia remains complex and encompasses
areas of uncertainty. A standardized approach to treating

Page 11 of 13

infants born to mothers with bacteremia might overlook
the complex interplay of microbial diversity, neonatal
immune responses, maternal health, and antimicrobial
stewardship. An individualized approach, guided by careful assessment of maternal and neonatal factors, could
provide more effective and judicious interventions, optimizing outcomes while minimizing potential harms [37].
This study has several limitations that should be taken
into consideration. Firstly, its retrospective nature inherently limits the ability to establish causal relationships
and might be subject to recall or documentation bias.
The study was not intended to address maternal sepsis
as a whole, as it requires broader clinical and laboratory
criteria than those explored here. Additionally, the study
did not correlate organisms isolated from other clinical samples from the mother where available with theneonatal blood culture as the main focus was on bacteremia associations. It is therefore possible that maternalacquisition, but not overt maternal bacteremia would still
have played a role in the development of EONS with orwithout neonatal bacteremia. Furthermore, this study
did not examine the interrelation between underlying
clinical diagnoses, effective antibiotic therapy, specificorganism isolates, and the occurrence of bacteremia inthese women. Therefore, the sources and mechanismsof bacteremia remain subjects for investigation in future
research. Moreover, cultures may have been obtained
more frequently from sick women, and we lacked dataon antenatal antimicrobial treatment or bacterial resistance patterns, which could have resulted in more positive
maternal and possibly neonatal cultures. Finally, despiteusing a high cutoff for CRP values, many NICUs do not
use CRP in the diagnosis of sepsis or use different cutoff
values. This variation could have led to an over-diagnosis
of culture-negative sepsis in our study.

Conclusion
Neonates born to bacteremic mothers, especially thosewith GP bacteria such as GBS, are at higher risk of developing EONS, underscoring the importance of prompt
detection and management. GP bacteremia, notably
GBS, is prevalent during labour and term gestationand can occur in mothers with negative GBS screening
results. This necessitates vigilant monitoring and timely
interventions for affected neonates. The 9.9% EONS ratein these neonates born to mothers evaluated for sepsis,
nearly doubling with confirmed maternal bacteremia,
highlights the need for further studies, including placental cultures and detailed maternal health assessments,
to deepen understanding of maternal-neonatal infection
dynamics. Moreover, further studies are needed to elucidate the distinct roles of various bacterial types in EONS.

Gad et al. BMC Pediatrics(2024) 24:526

Acknowledgements
Special thanks to the entire NICU and infection control teams in WWRC who
provide high-quality care to our newborns.
Authors’ contributions
AG conceptualized and designed the study, drafted the protocol, supervised
data collection, and drafted the first manuscript. MA submitted the study
protocol and supervised data collection. RT, HA, MI, RA, and AA collected thedata for the study. RT coordinated the data collection. PC and AG performed
the statistical analysis. MH and HP provided microbiology data and reviewed
the manuscript. MAAB critically reviewed and submitted the first draft of themanuscript. All authors have read and agreed to the published version of themanuscript.
Funding
This work was funded and supported by the Medical Research Center (MRC),
Hamad Medical Corporation, Doha, Qatar (Protocol number MRC-01–21-427).

Page 12 of 13

5.
6.

7.

8.

9.

Availability of data and materials
The datasets generated for this study are available on reasonable request to thecorresponding author. Data requests should be made to Agad2@hamad.qa.

10.

Declarations

11.

Ethics approval and consent to participate
This research study was approved by the Institutional Review Board (IRB)of the Medical Research Center, Hamad Medical Corporation, Doha, Qatar(MRC-01–21-427). A waiver for the requirement of informed consent from themothers whose records were analyzed was granted by the Chair of the Medical Research Center on the grounds of being a minimal-risk study. All methods
were performed following the relevant guidelines and regulations. Written
informed consent was obtained from the individuals for the publication of any
potentially identifiable images or data included in this article.
Consent for publication
Not applicable.
Competing interests
The authors declare no competing interests.
Author details
1
Neonatal Intensive Care Unit, Women’s Wellness and Research Center, Hamad
Medical Corporation, Doha, Qatar. 2 Pediatric Department, Weill Cornell
Medicine, Doha, Qatar. 3 Division of Pediatric Nephrology, University of Miami,
Miami, FL, USA. 4 Department of Medical Education, Hamad Medical Corporation (HMC), Doha, Qatar. 5 Medical Research Center, Hamad Medical Corporation (HMC), Doha, Qatar. 6 Microbiology Division, Department of Laboratory
Medicine and Pathology, Hamad Medical Corporation, Doha, Qatar.

12.
13.
14.
15.

16.
17.
18.
19.

Received: 18 October 2023 Accepted: 29 July 2024
20.

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