Diagnostic value of neutrophil-to-lymphocyte and platelet-to-lymphocyte ratio to predict recurrent pregnancy loss and abortion; a systematic review and meta-analysis

OBJECTIVE

This systematic review and meta-analysis aimed to evaluate the diagnostic value of the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) in women with a history of abortion (missed and threatened) and recurrent pregnancy loss (RPL) in comparison with healthy pregnancies.

METHODS

Electronic databases including MEDLINE, Scopus, Web of Science, Embase, and Cochrane Library were searched for NLR and PLR in women who experienced early pregnancy loss up to January 1, 2023 with a combination of proper keywords. Meta-analysis was done for comparison with three or more studies and summary estimates were measured.

RESULTS

A total of 390 citations were retrieved initially, and after screening, 16 articles were deemed eligible for the final review. Among these, 14 studies underwent meta-analysis. The meta-analysis revealed that the standard mean of the NLR was significantly higher in abortion cases compared to the control group. However, there was no significant difference in the PLR between the pregnancy loss group and the control group.

CONCLUSION

NLR was significantly higher among RPL patients compared to the control group, according to these data, NLR may be capable of being used in the diagnosis of RPL as an easy, cheap, and accessible modality. Further studies, which take these variables into account, will need to be undertaken to determine the diagnostic value of NLR and PLR in early pregnancy loss.

Relationship between platelet activation markers and spontaneous abortion: A meta-analysis

Numerous studies have indicated that mean platelet volume (MPV) and platelet distribution width (PDW) were correlated with spontaneous abortion (SAB), but the results were contradictory. Hence, we performed a meta-analysis to assess the association of MPV and PDW with SAB. We systematically searched on China National Knowledge Internet, PubMed, and Embase up to May 2022 to retrieve eligible studies. The synthesized standard mean difference (SMD) with a 95% confidence interval (CI) was used to evaluate the correlation of MPV and PDW with SAB. A total of 20 studies were finally included in this meta-analysis. The pooled analysis results showed that PDW was markedly increased in patients with SAB versus women with a healthy pregnancy (SMD = 1.03; 95% CI: 0.51-1.54; p = 0.0001), while there were no significant differences in MPV between women with SAB and those with healthy pregnancy (SMD = 0.19; 95% CI: -0.26 to 0.65; p = 0.40). Therefore, PDW may serve as a potential marker for predicting SAB. However, homogeneous and multiethnic studies with larger sample sizes are warranted to validate our findings due to several limitations in this meta-analysis.

Association of subclinical markers of inflammation with preterm premature rupture of membranes and adverse neonatal results: a case control study

AIM

The study aims to investigate the relationship between subclinical inflammatory factors, which are known to be closely related to inflammation, with preterm premature rupture of membranes (PPROM) and adverse postpartum outcomes.

MATERIALS AND METHODS

The case control type study was conducted between January 1, 2021, and January 2022. 525 pregnant women, including 272 PPROM and 253 normal patients, were added to the study.

RESULTS

There was a positive relationship between PPROM and PCT (platelet crit), MPV (mean platelet volume), NLR (neutrophil-to-lymphocyte ratio), and MLR (monocytes to lymphocyte ratio) values. ROC analysis, PCT > 0.19, MPV > 8.78, NLR > 2.82, and MLR > 0.24 were significantly related to improved risk of PPROM (P < 0.05). In logistic regression analysis, a one-unit rise in PCT resulted in a 3.9-fold rise in RDS risk and a one-unit increase in NLR resulted in a 1.6-fold significant rise in sepsis risk (p < 0.05).

CONCLUSION

NLR and PCT parameters were found to be related to adverse neonatal outcomes.

Could fibrinogen to albumin ratio be a predictive marker for recurrent pregnancy loss

AIMS

Recurrent pregnancy loss (RPL) is usually defined by two or more consecutive clinical miscarriages, which causes psychological trauma for couples. In this study, we aimed to investigate the predictive role of fibrinogen to albumin ratio (FAR) in patients with RPL.

METHODS

Pregnant women in their first trimester of pregnancy were included in the study and divided into two groups as RPL patients (n: 44) and patients with no previous recurrent miscarriage (n: 60) as control group. Demographical parameters and routine blood parameters (fibrinogen, D-dimer, FAR, neutrophil to lymphocyte ratio [NLR], platelet count, main platelet volume [MPV], and red cell distribution width [RDW] values) were compared between the RPL group and the control group.

RESULTS

The groups were determined to be statistically different in regard to gravidity and parity (P < .001). The difference between the groups was statistically different in regard to fibrinogen (mg/dL), albumin (g/dL), FAR (%), NLR (%), RDW-coefficient of variation (%), RDW-standard deviation (fl), and platelet counts (10^-3 /μL). However, MPV (fl) and D-dimer (μg/L) levels were similar in both groups. The receiver operating characteristic curve analysis revealed that the NLR levels were 84.1% sensitive and 75% specific with a cut-off value of 4.27 and the FAR levels were 79.5% sensitive and 88.3% specific with a cut-off value of 105.69 for predicting RPL.

CONCLUSION

Our results indicate that the FAR and NLR levels seem to be effective parameters for predicting RPL with high sensitivity and specificity.

Can Derived Neutrophil-to-Lymphocyte Ratio, Platelet-to-Lymphocyte Ratio, and Delta Neutrophil Index Predict Spontaneous Abortion?

OBJECTIVE

To evaluate the efficacy of complete blood count indices for the prediction of miscarriage.

MATERIALS AND METHODS

A retrospective case-control study was conducted in a tertiary hospital. This study consisted of 389 cases (32 elective and 193 spontaneous abortions, 164 healthy pregnancies). Maternal demographic characteristics, complete blood cell (CBC) parameters, neutrophil-lymphocyte ratio (NLR), derived NLR, systemic inflammatory immune index (SII), platelet-to-lymphocyte ratio (PLR), and delta neutrophil index (DNI) that were in the routine first trimester CBC were compared between groups.

RESULTS

There were no significant differences among groups in terms of demographic and obstetric characteristics. Statistically significant differences were observed for Hb, white blood cell (WBC), lymphocyte (L), NLR, SII, and PLR between the subgroups (p=0.003, p=0.045, p=0.000, p=0.002, p=0.043, p=0.010, respectively). There were no significant differences among groups in terms of the remaining parameters. When healthy pregnancies and spontaneous abortions were compared, statistically significant differences were detected for NLR, SII, PLR (p=0.001, p=0.039, and p=0.000, respectively). Moreover, when healthy pregnancies and elective abortions were compared, only NLR was found as statistically different (p=0.050). Area under curve (AUC) was calculated for PLR as 0.659 (%95 CI: 0.582-0.735) and a cut-off value of 158.1 was found with highest sensitivity and specificity (60.6 % and 61.6%, respectively) according to the results obtained from Youden's index. AUC was calculated for NLR as 0.591 (%95 CI: 0.507-0.675) and a cut-off value of 3.135 was found with highest sensitivity and specificity (56% and 54.5%) according to the results obtained from Youden's index.

CONCLUSION

In conclusion, decreased PLR and NLR levels may be used as practical and cost-effective markers for the prediction of miscarriages.

Neutrophil and Neutrophil-to-Lymphocyte Ratio as Clinically Predictive Risk Markers for Recurrent Pregnancy Loss

We aimed at exploring the value of neutrophil and neutrophil-to-lymphocyte ratio (NLR) as predictive risk markers for recurrent pregnancy loss (RPL) by conducting a retrospective case-control study and a systematic review and meta-analysis. This retrospective case-control study was conducted in an academic hospital from January 2012 to June 2018 and 133 cases of women with RPL and 140 control women. In parallel, we conducted a systematic review and meta-analysis on the value of NLR and neutrophil in RPL risk assessment. Neutrophil and NLR were higher in the women with RPL than those in the controls (median [interquartile range]: 4.32 [3.31-6.18] vs. 3.76 [2.78-4.81], p = 0.001; 2.17 [1.47-3.16] vs. 1.74 [1.40-2.34], p = 0.001). After the cut-off value of the neutrophil and NLR was determined to be 6.3 × 10⁹/L and 3.16, the prevalence of RPL became significantly increased in the high-neutrophil and the high-NLR group compared to the low-neutrophil and the low-NLR group (76.3% vs. 44.2%, p < 0.001; 66.6% vs. 44.5%, p < 0.001). Univariate logistic regression analysis indicated that high-neutrophil and high-NLR were risk factors for RPL, with ORs of 4.06 (95% CI: 1.84-8.95) and 2.49 (95% CI: 1.31-4.71), respectively. Multivariate logistic regression analysis indicated that high-neutrophil was a risk factor for RPL, with OR of 4.91 (95% CI: 1.66-14.50). Meta-analysis of 5 case-control studies (including the present study) indicated that increased neutrophil and NLR may be risk factors for RPL, with SMDs of 0.63 (95% CI: 0.45-0.80) and 0.61 (95% CI: 0.39-0.83). Based on current findings and the meta-analysis, this study indicated that neutrophil and NLR might be valuable for predicting RPL; more studies with large sample are needed to verify this conclusion. The mechanism of the association between neutrophil and RPL needs to be explored in further studies.

Platelet indices as a predictive marker in neonatal sepsis and respiratory distress in preterm prelabor rupture of membranes

Preterm Prelabor rupture of membranes (PPROM) accompanies 2-3% of all pregnancies and 1/3rd of all preterm deliveries leading to intraamniotic infection, postpartum infections, sepsis along with perinatal morbidity and mortality worldwide. Early diagnosis and treatment can prevent the complications of PPROM and improve mother and child health. The platelet indices (platelet count, Mean platelet volume, Plateletcrit and Immature platelet fraction) could be a useful predictive parameters in PPROM, as platelets are acute phase reactants and there parameters may vary with inflammation and increased platelet consumption/production. In the present study, Mean Platelet volume (MPV) levels showed significant increase in cases as compared to controls (10.47 ± 1.92 fl Vs 8.84 ± 1.30 fl; P < 0.004). Plateletcrit (PCT) levels were also significantly increased in cases with respect to controls (0.22 ± 0.10% Vs 0.18 ± 0.05%; P = 0.004). Immature platelet fraction (IPF) is significantly increased in cases than in control subjects (8.73 ± 6.67% Vs 4.43 ± 1.75%; P < 0.001). Also, Mean Platelet volume (MPV) levels were found to be significantly higher in subjects whose neonate had developed sepsis(11.39 ± 1.69 fl Vs 8.91 ± 1.31 fl; P < 0.001) and respiratory distress (10.62 ± 2.09 fl Vs 9.26 ± 1.56 fl; P = 0.003). Similarly, PCT was significantly higher in groups with positive neonatal sepsis (0.32 ± 0.74% Vs 0.19 ± 0.65%; P = 0.010) and with respiratory distress (0.24 ± 0.78% Vs 0.18 ± 0.59%; P < 0.001). Levels of IPF were also increased in positive neonatal sepsis group (10.11 ± 6.27% Vs 5.06 ± 4.07%; P < 0.001) and respiratory distress group (9.11 ± 6.38% Vs 5.54 ± 4.43%; P = 0.009). The findings suggest that maternal platelet parameters (MPV, PCT and IPF) can be utilized as evidence of early predictors of development of neonatal sepsis and respiratory distress and may be considered as a predictive markers for adverse neonatal outcome.

Can neutrophil-to-lymphocyte and monocyte-to-lymphocyte ratios be useful markers for predicting missed abortion in the first trimester of pregnancy?

AIM

To explore whether neutrophil-to-lymphocyte ratio (NLR) and monocyte-to-lymphocyte ratio (MLR) could predict missed abortion (MA) at 7-13 week's gestation.

METHODS

A total of 363 women with a diagnosis of MA and 232 women with normal pregnancy at 7-13 week's gestation, who visited our hospital from June 2012 to May 2018 were retrospectively analyzed. At 7 week's gestation, total and differential leukocyte counts, NLR and MLR were compared between women with MA (n = 69) and normal controls (n = 53). The receiver operating characteristic curve was used to select the optimal indicator and its cut-off point. The role of the optimal indicator was further assessed at 8-13 week's gestation.

RESULTS

The mean white blood cell counts, the mean neutrophil counts, the median monocyte counts, the mean NLR and the median MLR in women with MA were significantly lower than those in normal controls (P < 0.05, respectively).The neutrophil counts had the highest area under the curve (AUC) value of 0.772 (95% confidence interval 0.675-0.869) with a cut-off value of 4.870 × 10⁹ /L, and the sensitivity was 72.46%, the specificity was 69.81%, positive predictive value was 75.76%, and negative predictive value was 66.07%. In addition, the neutrophil counts were also significantly lower in MA groups than those in normal controls at 8-13 week's gestation, and all had the highest AUC values.

CONCLUSION

Neutrophil counts may predict MA in the first trimester of pregnancy, which may provide a promising marker to diagnose missed abortion as early as 7 week's gestation.

The role of neopterin and anti-Mullerian hormone in unexplained recurrent pregnancy loss - a case-control study

This case-control study was conducted to assess whether neopterin (NP) and anti-Mullerian hormone (AMH) can be used as markers in the condition of unexplained recurrent pregnancy loss (RPL). To the best of our knowledge, this is the first work which has studied the association between AMH, NP and RPL. A total of 110 patients were included; 53 women who had at least two consecutive unexplained miscarriages (<12 weeks) made up the study group. The control group was established from 57 women who never had a miscarriage and had at least one healthy birth history. Peripheral blood samples were collected from each patient to analyse the AMH and NP concentrations. The results suggested that mean level of AMH (1.38 ± 0.683 ng/ml) in the patient's group was significantly lower than the control group (1.84 ± 0.718 ng/ml). The mean levels of NP were significantly higher in the patient group (1.69 ± 0.486 vs. 1.38 ± 0.431 ng/ml). IMPACT STATEMENT What is already known about this subject? To the best of our knowledge, no previous studies about the association among AMH, NP and RPL were found in the literature. What do the results of this study add? This pioneer study demonstrates the significant relationship between the unexplained RPL with the increased levels of NP and decreased AMH. What are the implications of these findings for clinical practice and/or further research? NP and AMH may play an effective role in illuminating the condition of unexplained RPL. High levels of NP and low values of AMH in patients with RPL can be used as predictive markers for this clinical situation. If the causes of high levels of NP and low levels of AMH can be better illuminated, new treatments towards these causes can be developed to help such patients become childbearing.