Maternal serum ferritin concentration in patients with preterm labor and intact membranes

High first trimester ferritin levels differ according to parity and are independently related to preterm birth: A prospective cohort study

INTRODUCTION

A considerable amount of neonatal morbidity and mortality worldwide is caused by preterm birth. To date, the underlying etiology of preterm birth has not been fully clarified. Previous studies demonstrate that inflammation is one of the pathological factors that might cause preterm birth, and that there is a difference between primiparous and multiparous women in immune response to pregnancy. The objective of this prospective cohort study was to investigate the role of two inflammatory markers, ferritin and C-reactive protein (CRP) and preterm birth, in first trimester women, stratified for parity. In addition, a possible association between high ferritin and CRP, and a possible association between high ferritin and CRP and preterm birth were assessed.

MATERIAL AND METHODS

A total of 2044 healthy, low-risk pregnant women from primary obstetric care in the Netherlands participated in this study. Their ferritin and CRP levels were evaluated at 12 weeks' gestation. Levels above the parity specific 95th percentile were defined as high. The main outcome of this study was to assess the presence of a possible association between parity specific high ferritin and CRP, and preterm birth. The secondary outcomes were the ferritin and CRP levels of women, stratified for parity, and the possible association between high ferritin and CRP levels. Logistic regression analysis was performed with preterm birth as a dependent variable and parity specific high ferritin and CRP as an independent variable, adjusting for age and history of preterm birth.

RESULTS

Ferritin levels decreased with increasing parity. Ferritin and CRP levels at 12 weeks' gestation were significantly higher in women with preterm birth. In primiparous women, high ferritin levels (OR: 2.5, CI: 1.14-5.38) and high CRP levels (OR: 5.0, CI: 2.61-9.94) were independently associated with preterm birth. In multiparous women, high ferritin levels (OR: 6.0, CI: 2.28-16.67) were independently associated with preterm birth while high CRP levels were not.

CONCLUSIONS

First trimester parity specific ferritin and CRP levels could play a part in predictive models for preterm birth, and further research for their additive role in preterm birth is needed.

Population-based study of serum ferritin in early pregnancy and adverse perinatal outcomes

BACKGROUND

Chronic placental inflammation is associated with preterm birth (PTB) and perinatal mortality. Ferritin is often elevated in chronic inflammatory conditions, but prior studies of its relation to PTB were restricted to ferritin measurement within pregnancy, were underpowered to detect rarer outcomes, and did not account for pre-existing maternal inflammatory conditions, such as inflammatory bowel or rheumatological disease.

OBJECTIVES

To evaluate whether an elevated ferritin level prior to pregnancy is associated with major adverse pregnancy outcomes.

METHODS

A population-based cohort study was completed using Ontario, Canada. Included were all Ontarian women with a hospital livebirth or stillbirth at ≥20 weeks' gestation, 2007-2018, and serum haemoglobin and ferritin measured as an outpatient within 120 days before conception. Excluded were women with a diagnosed iron overload disorder or a ferritin concentration <15 µg/L. The main exposure was a pre-pregnancy serum ferritin ≥95th percentile. Study outcomes included PTB < 37 weeks' gestation, including clinician-initiated and spontaneous PTB; PTB < 32 weeks; chorioamnionitis; and perinatal death. Relative risks (RR) and 95% confidence intervals (CI) were calculated for each study outcome, comparing a serum ferritin concentration ≥95th vs <5th percentile (the referent), while adjusting maternal age, residence, haemoglobin concentration, diabetes mellitus, inflammatory bowel disease, illicit drug/tobacco use, chronic kidney disease, chronic hypertension, sickle-cell disease or thalassaemia, and rheumatological conditions.

RESULTS

Among 89 847 births, a preconceptional maternal serum ferritin ≥95th (112.0 μg/L) vs <5th (16.9 μg/L) percentile was associated with an adjusted relative risk (aRR) of 1.34 (95% CI 1.15, 1.57) for PTB, including spontaneous and clinician-initiated PTB. Results were equivocal for chorioamnionitis (aRR 1.23, 95% CI 0.81, 1.86), and there was no association with perinatal mortality (aRR 0.94, 95% CI 0.55, 1.61).

CONCLUSION

A high preconceptional ferritin concentration is associated with some adverse perinatal outcomes.

Role of maternal serum ferritin in prediction of preterm labour

The aim of this study was to evaluate the value of measurement of serum ferritin level in pregnant women to predict preterm labour. The study included 236 women whose haemoglobin (Hb) levels were ≥10.5 gm/dl and gestational age (GA) was less than 30 weeks. Serum ferritin levels were measured at 30 weeks of gestational age. At the end of the study, 23 women delivered with preterm premature rupture of membrane (PPROM) and 17 women delivered before 37 weeks but without PROM (study group). The rest of the pregnant women (196 women) delivered between 37 and 40 weeks (control group). We found a significant difference between the two groups with respect to serum ferritin level. The cut off value of serum ferritin between the two groups was 31 ng/ml with sensitivity 92.8%, specificity 99.4%, positive predictive value 97.5%, negative predictive value 98.4% and accuracy 98.3%. Impact statement What is already known on this subject: maternal serum ferritin has been found to be elevated in women who delivered preterm. What the results of this study add: In this study, we have shown that serum ferritin 31 ng/ml is the optimal cut-point between preterm and full-term women. What the implications are of these findings for clinical practice and/or further research: Serum ferritin 31 ng/ml could be proposed as a potential helpful marker to predict preterm labour.

The value of acute phase reactants in predicting preterm delivery

OBJECTIVE

We aimed to determine the potential value of maternal serum levels of acute phase reactants in the prediction of preterm delivery in women with threatened preterm labor (TPL).

METHODS

Ninety-one pregnant women diagnosed with TPL and 83 healthy pregnant women as a control group were included in this prospective controlled study. All the pregnant women were followed until delivery and obstetric data and the serum levels of acute phase reactants were recorded for each participant. The study group was further divided into two groups according to the gestational age at delivery, which include women delivering prematurely and the ones who gave birth at term.

RESULTS

Serum albumin levels were significantly lower and mean serum ferritin levels were significantly higher in the study groups when compared the control group.

CONCLUSION

Although an association between decreased serum albumin level and TPL, also between increased serum ferritin levels and preterm birth and low birth weight were demonstrated, more extensive studies are needed to clarify the potential use of the acute phase reactants in the prediction of preterm birth.

High maternal serum ferritin in early pregnancy and risk of spontaneous preterm birth

Previous studies have reported inconsistent associations between maternal serum ferritin concentrations and the risk of spontaneous preterm birth (sPTB). The aim of the present study was to examine the association between Fe biomarkers, including serum ferritin concentrations, and the risk of total ( 75th percentile ( ≥ 43 μg/l) (OR 1.49, 95% CI 1.06, 2.10) and >90th percentile ( ≥ 68 μg/l) (OR 1.92, 95% CI 1.25, 2.96). Increased odds of early and moderate-to-late sPTB were associated with ferritin levels >90th percentile (OR 2.50, 95% CI 1.32, 4.73) and >75th percentile (OR 1.56, 95% CI 1.03, 2.37), respectively. No association was found between the risk of sPTB and elevated sTfR levels or Fe deficiency. In conclusion, elevated maternal serum ferritin levels in early pregnancy are associated with an increased risk of sPTB from 34 weeks of gestation. The usefulness of early pregnancy ferritin levels in identifying women at risk of sPTB warrants further investigation.

The diagnostic value of cervicovaginal and serum ferritin levels in midgestation time to predict spontaneous preterm delivery

BACKGROUND

The aim of this study was to determine diagnostic value of cervicovaginal ferretin and serum ferretin levels at midgestation time in predicting preterm delivery in singleton pregnancies.

PATIENTS AND METHODS

A diagnostic test study through a prospective cohort design was carried out on 300 singleton pregnant women in 2012. A blood sample was obtained from all the patients within 22-24 gestational weeks for laboratory assessment of serum ferretin, and cervicovaginal sample was also taken to assess cervicovaginal ferritin level. Ferritin levels were compared between term and preterm deliveries at 37, 34 and 32 weeks of gestation. Receiver operating characteristics (ROC) curves were plotted to assess the diagnostic test values.

RESULTS

Mean serum ferritin level was 55.38 [standard deviation (SD 23.8)] ng/mL in term deliveries versus a mean of 91.27 (SD 25.2) ng/mL in preterm deliveries, which showed a statistically significant difference (P < 0.001). The ferritin levels in cervicovaginal term delivery group had mean of 11.29 (SD 16.2) ng/mL compared with a mean of 21.95 (SD 10.1) ng/mL among those with preterm delivery before 37 weeks of gestational age(P < 0.001). The cervicovaginal ferritin level had a moderate to good diagnostic value with an area under curve being above 0.8 for all assessments. The serum ferritin level had a moderate to good diagnostic value with an area under curve being above 0.8 for all assessments. In both tests, its diagnostic value was higher for predicting preterm delivery at earlier gestational age.

CONCLUSIONS

The results of this study indicate that high levels of serum and cervicovaginal ferritin in singleton pregnancies may alert the clinician of the risk of preterm delivery. Serum and cervicovaginal ferritin measurement at midgestation may be used as a predictive scale for preterm delivery in singleton pregnancies.

Predictors of preterm birth in patients with mild systemic lupus erythematosus

OBJECTIVE

While increased disease activity is the best predictor of preterm birth in women with systemic lupus erythematosus (SLE), even women with low disease activity are at increased risk of this complication. Biomarkers that would identify at-risk pregnancies could allow interventions to prevent preterm birth.

METHOD

Measures of SLE activity, inflammation, placental health and renal function between 20 and 28 weeks gestation (mid-gestation) were correlated to preterm birth and gestational age at delivery in a prospective cohort of pregnant women with SLE.

RESULT

Of the 40 pregnancies in 39 women, all with mild-moderate SLE disease, 9 (23.7%) of the 38 live births were delivered preterm. Low C4 was the only marker of SLE activity associated with younger gestational age at delivery. Elevated ferritin and lower oestradiol correlated with younger gestational age at delivery. Renal function remained normal during all pregnancies at mid-gestation and did not correlate with preterm birth. Higher serum uric acid, however, correlated with younger gestational age at delivery.

CONCLUSIONS

In women with SLE with mild-moderate disease activity, ferritin, oestradiol and uric acid levels at mid-gestation may predict preterm birth. These markers may prove to be clinically useful in identifying pregnancies at particularly high risk for adverse outcomes.

Can leukocyte count during the first trimester of pregnancy predict later gestational complications?

PURPOSE

To examine whether an association exists between maternal leukocyte count in the first trimester of pregnancy and the risk for development of obstetric complications.

METHODS

The study population included all the registered births (n = 33,866) with available white blood cell count (WBC) from the first trimester of pregnancy, during 2000-2010 in a tertiary medical center. The leukocyte count was sorted by the following groups: WBC < 3.5 10 × 9/l, WBC = 3.5 10 × 9/l-13.8 10 × 9/l, and WBC > 13.8 10 × 9/l. These groups were compared regarding obstetrical characteristics and perinatal outcomes. Multiple logistic regression models were used to control for confounders.

RESULTS

The study population included 33,866 deliveries, of these 0.94 % had leukocytosis WBC > 13.8 10 × 9/l. Women with leukocytosis delivered significantly earlier, were more likely to be Jewish, and in their first pregnancy. There were significantly higher rates of preterm delivery before 37 weeks, fertility treatments, hypertensive disorders, gestational diabetes mellitus, and cesarean section among these patients. There was no significant difference between the groups regarding preterm premature rupture of membranes (PPROM) and chorioamnionitis. Women with leukocytosis during the first trimester had significantly higher rates of fetuses who were small for gestational age and with birth weight <2,500 g. Multivariable analysis showed a significant association between preterm delivery before 37 weeks and leukocytosis during the first trimester of pregnancy (p = 0.003).

CONCLUSIONS

Leukocytosis during the first trimester is significantly associated with an increased risk for obstetrical complications, in particular preterm delivery. Nevertheless, further studies should focus on women with leukocytosis during the first trimester in order to verify our results.