Obstetric impact of anaemia in pregnant women in United Arab Emirates

Hemostatic biomarkers associated with postpartum hemorrhage: a systematic review and meta-analysis

Postpartum hemorrhage (PPH) is a leading cause of maternal morbi-mortality. Although obstetric risk factors are well described, the impact of predelivery hematologic and hemostatic biomarkers remains incompletely understood. In this systematic review, we aimed to summarize the available literature on the association between predelivery hemostatic biomarkers and PPH/severe PPH. Searching MEDLINE, EMBASE, and CENTRAL databases from inception to October 2022, we included observational studies on unselected pregnant women without bleeding disorder reporting on PPH and on predelivery hemostatic biomarkers. Two review authors independently performed title, abstract and full-text screening, upon which quantitative syntheses of studies reporting on the same hemostatic biomarker were conducted, calculating the mean difference (MD) between women with PPH/severe PPH and controls. A search on 18 October 2022 yielded 81 articles fitting our inclusion criteria. The heterogeneity between studies was considerable. With regard to PPH, the estimated average MD in the investigated biomarkers (platelets, fibrinogen, hemoglobin, Ddimer, activated partial thromboplastin time, and prothrombin time) were not statistically significant. Women who developed severe PPH had lower predelivery platelets than controls (MD = -26.0 109/L; 95% confidence interval, -35.8 to -16.1), whereas differences in predelivery fibrinogen concentration (MD = -0.31 g/L; 95% confidence interval, -0.75 to 0.13) and levels of factor XIII or hemoglobin were not statistically significant in women with and without severe PPH. Predelivery platelet counts were, on average, lower in women with severe PPH compared with controls, suggesting the potential usefulness of this biomarker for predicting severe PPH. This trial was registered at the International Prospective Register of Systematic Reviews as CRD42022368075.

Effect of Intrapartum Maternal Hemoglobin on Mode of Delivery and Short-Term Neonatal Outcome: A Systematic Review

Importance

Maternal anemia in pregnancy is a common condition worldwide and is considered a risk factor for adverse neonatal and maternal outcome. Also high hemoglobin (Hb) levels are associated with adverse pregnancy outcomes. However, studies regarding the influence of intrapartum maternal Hb on mode of delivery and short-term neonatal outcome are limited and contradicting.

Objective

The aim of this study was to provide an overview of current evidence regarding associations between intrapartum maternal Hb levels and mode of delivery and short-term neonatal outcome. In addition, we propose directions for future research.

Evidence Acquisition

We systematically searched the electronic PubMed, EMBASE, and Cochrane databases for studies on maternal Hb levels and mode of delivery maternal and short-term neonatal outcome until January 2021. Eligible articles and their references were independently reviewed by 2 authors. Assessment was based on methodological quality and study results.

Results

We included 14 studies that evaluated the level of maternal pH in relation to clinical outcome, 6 studies on mode of delivery, 10 studies on Apgar score, 1 study on fetal distress, 2 studies on neonatal intensive care unit admission, 1 study on umbilical cord pH, and 5 studies on perinatal mortality.

Conclusions and Relevance

We found a trend toward an increased risk of cesarean delivery in anemic woman. Concerning the short-term neonatal outcomes, the evidence is conflicting, and included studies are too heterogenic to compare. Furthermore, various studies indicated a relation between high Hb levels and increased perinatal mortality. Therefore, we especially recommend attention to elevated Hb levels.

Target Audience

Obstetricians and gynecologists, family physicians.

Learning Objectives

After completing this activity, the learner should be better able to describe how Hb levels affect mode of delivery and short-term neonatal outcome, and identify abnormal Hb levels and propose appropriate treatment and monitoring recommendations.

Maternal and birth cohort studies in the Gulf Cooperation Council countries: a systematic review and meta-analysis

BACKGROUND

We systematically reviewed and chronicled exposures and outcomes measured in the maternal and birth cohort studies in the Gulf Cooperation Council (GCC) countries and quantitatively summarized the weighted effect estimates between maternal obesity and (1) cesarean section (CS) and (2) fetal macrosomia.

METHODS

We searched MEDLINE-PubMed, Embase, Cochrane Library, Scopus, and Web of Science electronic databases up to 30 June 2019. We considered all maternal and birth cohort studies conducted in the six GCC countries (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and United Arab Emirates (UAE)). We categorized cohort studies on the basis of the exposure(s) (anthropometric, environmental, medical, maternal/reproductive, perinatal, or socioeconomic) and outcome(s) (maternal or birth) being measured. Adjusted weighted effect estimates, in the form of relative risks, between maternal obesity and CS and fetal macrosomia were generated using a random-effects model.

RESULTS

Of 3502 citations, 81 published cohort studies were included. One cohort study was in Bahrain, eight in Kuwait, seven in Qatar, six in Oman, 52 in Saudi Arabia, and seven in the UAE. Majority of the exposures studied were maternal/reproductive (65.2%) or medical (39.5%). Birth and maternal outcomes were reported in 82.7% and in 74.1% of the cohort studies, respectively. In Saudi Arabia, babies born to obese women were at a higher risk of macrosomia (adjusted relative risk (aRR), 1.15; 95% confidence interval (CI), 1.10-1.20; I2 = 50%) or cesarean section (aRR, 1.21; 95% CI, 1.15-1.26; I2 = 62.0%). Several cohort studies were only descriptive without reporting the magnitude of the effect estimate between the assessed exposures and outcomes.

CONCLUSIONS

Cohort studies in the GCC have predominantly focused on reproductive and medical exposures. Obese pregnant women are at an increased risk of undergoing CS delivery or macrosomic births. Longer-term studies that explore a wider range of environmental and biological exposures and outcomes relevant to the GCC region are needed.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42017068910.

Associations between iron deficiency anemia and clinical features among pregnant women: a prospective cohort study

Background

Iron deficiency anemia (IDA) during pregnancy is a common and preventable disorder. It remains a contributing factor to maternal morbidity and mortality and is associated with high perinatal mortality rates.

Objective

To determine the prevalence of IDA and its associated clinical features among pregnant women.

Methods

This analytical prospective cohort study included 1,579 pregnant women who attended an antenatal clinic, Women’s Specialized Hospital, King Fahad Medical City, Riyadh, Saudi Arabia, between January 2018 and April 2018. The type of anemia and its associated maternal and fetal outcomes were determined.

Results

About 702 women were confirmed to have IDA, with a prevalence of 44.5 %. Most women (79.8%) were younger than 35 years. A low hemoglobin concentration was reported in 45 % of participants. The major type of anemia was microcytic hypochromic anemia (98.7%). More than half of the participants (57.3%) reported use of iron supplementation during pregnancy. IDA anemia was highest in pregnant women with gravidity >8 in 40 (56.3%) compared to normal pregnant women 31 (43.7%), and lowest in those with gravidity ≤2 in 281 (41.4%) compared to normal pregnant women 397 (58.6%). The difference was statistically significant, P=0.024. Similarly, this type of anemia was highest in those with parity of >3 (53.3%) and lowest in nulliparous women (39.3%) compared to normal pregnant women (46.7%) and (60.7%), respectively. This was statistically significant P=0.002. IDA had significantly (P=0.012) lower spontaneous vaginal delivery rates compared with normal pregnant women (44.5% vs 55.5%, respectively). IDA had significantly (P=0.017) lower antenatal fetal distress rates compared with normal pregnant women (68.5% vs 31.5%, respectively).

Conclusion

Anemia in general and microcytic hypochromic anemia in particular were significantly associated with higher gravidity and parity. The significant outcome associated with IDA during pregnancy was a lower rate of spontaneous vaginal delivery and antenatal fetal distress. Compliance with iron supplementation in order to prevent maternal and fetal adverse outcomes was observed.

Observations on the health of infants at a time of rapid societal change: a longitudinal study from birth to fifteen months in Abu Dhabi

Background

Rapid economic and cultural transition in the United Arab Emirates has been accompanied by a rise in chronic disease. Early childhood is known to affect health outcomes in adulthood. This prospective longitudinal study examined the general health of Emirati infants born in a government maternity hospital in the Emirate of Abu Dhabi in October 2002.

Methods

One hundred twenty-five women, who had recently given birth, were interviewed as part of a larger study encompassing a wide range of cultural, social, and behavioural aspects of health. They were then re-interviewed at three (n = 94), six (n = 59) and 15 months postpartum (n = 52). Data are presented using univariate statistics.

Results

In this study seven infants (6%) were born prematurely and four infants (3%) were classified as small for gestational age, while 11 (9%) of the infants weighed less than 2500 g. Low birth weight infants (LBW) were significantly more likely to require treatment in the neonatal intensive care unit (OR = 30.83, p = 0.00). Iron supplementation during pregnancy was associated with fewer underweight infants (OR = 3.92, p = 0.042). No associations were found between infant birth weight and maternal age, age at marriage, consanguinity, education level, current maternal employment, parity, pre-existing anaemia or anaemia in pregnancy, diabetes, folic acid intake, multivitamin intake or infant gender.

Maternally-reported infant health issues, vaccination, medication, breast-feeding and infant nutrition, and use of secure car seats are also reported.

Conclusions

The health of infants at birth in this UAE sample showed improvements compared to previous studies. The proportion of LBW infants is decreasing and continuing improvements in health care in the UAE are having a positive impact on infant health.

Laboratory prediction of primary postpartum haemorrhage: a comparative cohort study

BACKGROUND

Postpartum haemorrhage (PPH) is the leading cause of maternal deaths, the world over. The aim of this study was to determine laboratory parameters that could serve as risk factors for primary PPH.

METHODS

This comparative cohort study involved 350 pregnant women at term who were recruited consecutively from the Komfo Anokye Teaching Hospital, Kumasi, Ghana. PPH was defined as a measured blood loss ≥ 500 ml or enough to cause haemodynamic shock. Basic demographic data was gathered and blood was collected for laboratory assays before delivery. Univariate and multivariate logistic regression models were used to identify variables that were significantly associated with primary PPH.

RESULTS

Of the total recruited study participants (350), five declined to participate and 74 went through caesarean section, episiotomy or instrumental deliveries and were excluded. Of the remaining (271) study participants who went through spontaneous vaginal delivery, fifty five (55) were diagnosed with primary PPH (Group 1) and the remaining 216 were those who did not have PPH (Group 2). Demographic characteristics did not differ between the two groups (P > 0.05). Univariate analysis showed that AST (P = 0.043), urea (P < 0.001), creatinine (P = 0.002), urea-to-creatinine ratio (P = 0.014) and the proportion of abnormal peripheral blood smear (P < 0.001) was higher among women in Group 1 compared to those in Group 2. Women in Group 1 had a significantly lower haemoglobin concentration (10.7 g/dL) compared to those in Group 2 (12.1g/dL). Upon multivariate analysis, an abnormal peripheral blood smear (AOR = 2.9672), Hb, (AOR = 0.5791), moderate to severe anaemia (Hb <10 g/dL) (AOR = 3.1385), Urea (AOR = 3.6435) and intra-renal azotaemia (AOR = 0.1893) remained significant.

CONCLUSION

Many laboratory parameters are associated with primary PPH but only a few are independent risk factors. A total clinical work-up including laboratory evaluation of the independent blood variables identified in this study will help a great deal to identify individuals at high risk for PPH.

Mild anemia and pregnancy outcome in a Swiss collective

Background. Over half of all women in the world experience anemia during their pregnancy. Our aim was to investigate the relation between hemoglobin and iron status examined in second trimester and pregnancy outcome. Methods. In a prospective longitudinal study, 382 pregnant women were included. Blood samples were examined for hematological status and serum ferritin between 16 and 20 weeks and for hemoglobin before delivery. The adverse maternal and perinatal outcomes were determined. Regression analysis was performed to establish if anemia and low serum ferritin are risk factors for pregnancy complications. Results. There was no increase of complications in women with mild anemia and in women with depleted iron stores. The finding showed that mild iron deficiency anemia and depleted iron stores are not risk factors for adverse outcomes in iron supplemented women. Conclusions. Mild anemia and depleted iron stores detected early in pregnancy were not associated with adverse maternal and perinatal outcomes in iron supplemented women.

Anaemia, prenatal iron use, and risk of adverse pregnancy outcomes: systematic review and meta-analysis

OBJECTIVES

To summarise evidence on the associations of maternal anaemia and prenatal iron use with maternal haematological and adverse pregnancy outcomes; and to evaluate potential exposure-response relations of dose of iron, duration of use, and haemoglobin concentration in prenatal period with pregnancy outcomes.

DESIGN

Systematic review and meta-analysis

DATA SOURCES

Searches of PubMed and Embase for studies published up to May 2012 and references of review articles.

STUDY SELECTION CRITERIA

Randomised trials of prenatal iron use and prospective cohort studies of prenatal anaemia; cross sectional and case-control studies were excluded.

RESULTS

48 randomised trials (17 793 women) and 44 cohort studies (1 851 682 women) were included. Iron use increased maternal mean haemoglobin concentration by 4.59 (95% confidence interval 3.72 to 5.46) g/L compared with controls and significantly reduced the risk of anaemia (relative risk 0.50, 0.42 to 0.59), iron deficiency (0.59, 0.46 to 0.79), iron deficiency anaemia (0.40, 0.26 to 0.60), and low birth weight (0.81, 0.71 to 0.93). The effect of iron on preterm birth was not significant (relative risk 0.84, 0.68 to 1.03). Analysis of cohort studies showed a significantly higher risk of low birth weight (adjusted odds ratio 1.29, 1.09 to 1.53) and preterm birth (1.21, 1.13 to 1.30) with anaemia in the first or second trimester. Exposure-response analysis indicated that for every 10 mg increase in iron dose/day, up to 66 mg/day, the relative risk of maternal anaemia was 0.88 (0.84 to 0.92) (P for linear trend<0.001). Birth weight increased by 15.1 (6.0 to 24.2) g (P for linear trend=0.005) and risk of low birth weight decreased by 3% (relative risk 0.97, 0.95 to 0.98) for every 10 mg increase in dose/day (P for linear trend<0.001). Duration of use was not significantly associated with the outcomes after adjustment for dose. Furthermore, for each 1 g/L increase in mean haemoglobin, birth weight increased by 14.0 (6.8 to 21.8) g (P for linear trend=0.002); however, mean haemoglobin was not associated with the risk of low birth weight and preterm birth. No evidence of a significant effect on duration of gestation, small for gestational age births, and birth length was noted.

CONCLUSIONS

Daily prenatal use of iron substantially improved birth weight in a linear dose-response fashion, probably leading to a reduction in risk of low birth weight. An improvement in prenatal mean haemoglobin concentration linearly increased birth weight.

Anemia--prevalence and risk factors in pregnancy

BACKGROUND

To assess the prevalence of decreased iron stores and anemia in pregnant women. To determine whether the risk factors: socio-demographic background, age, BMI, and parity are associated with abnormal hemoglobin concentrations and/or abnormal iron status.

METHODS

A longitudinal study was carried out at the Department of Obstetrics, University Hospital of Zurich to establish the risk factors and prevalence of the decreased iron stores and anemia in early pregnancy. In order to determine the hematological parameters and ferritin levels, venous blood samples of 470 singleton pregnancies between 16 and 20 pregnancy weeks were collected. According to hemoglobin and iron status, the patients were divided into four groups: patients with iron deficiency anemia, patients with decreased iron stores, patients with anemia for other reasons and normal patients. The determinants socio-demographic background, age, BMI and parity were explored using multiple logistic regression analysis.

RESULTS

The prevalence of decreased iron stores (ferritin<20 μg/l) was observed in 31.8% of subjects (149/470) and anemia (Hb<110 g/l) in 18.5% (87/470). The prevalence of iron deficiency anemia was higher among women coming from former Yugoslavia and developing countries (p=0.004 and p=0.012). In patients coming from developing countries, a significant increase of anemia for other reasons was observed (p=0.027) and in patients older than 30 years, a significant increase of decreased iron stores (p=0.018).

CONCLUSIONS

In our study population with low parity, the prevalence of abnormal hemoglobin and abnormal iron status was 50.2% (236/470), and socio-demographic background was the most important risk factor of anemia.

Determinants of birthweight: gender based analysis

The objective of this cross sectional study is to look at determinants of birth weight and their association with the gender of the baby in 2,795 full term children living in the occupied Palestinian territory, derived from a stratified random sample of 2,994 households in the West Bank and 2,234 households in the Gaza Strip. The response rate was 85%. Multivariable analysis using analysis of variance for mixed models showed that sex and birth order, maternal age and education and to a lesser extent region were determinants of birth weight for all children. The effect of maternal education on birth weight differed for female and male infants, tending to be relatively unchanged for male infants and with mean birth weights increasing with maternal education in female infants. The effect of birth order differed by maternal age, with mean birth weight increasing with maternal age for first and second births; but being unaffected by maternal age for infants of birth order greater than two. We conclude that birth weight is influenced by common biological determinants across cultures, but is also influenced by social, ethnic, and environmental factors that are culture specific, of which some might be gender related.