Magnitude of Thrombocytopenia and Associated Factors among Pregnant Women Attending the Antenatal Care Service Unit of Wachemo University Nigist Ellen Mohammed Comprehensive Specialized Hospital Hosanna, Southern Ethiopia

Background Thrombocytopenia is the second most common hematological disorder in pregnancy after anemia worldwide and affects 7-8% of all pregnancies. Pregnant women with thrombocytopenia have complications of excessive bleeding during or after childbirth, exudation at the cesarean section, and neonatal thrombocytopenia. Therefore, the main aim of this study was to assess the magnitude of thrombocytopenia and its associated factors among pregnant women attending the Antenatal Care Service Unit of Wachemo University Nigist Ellen Mohammed Comprehensive Specialized Hospital Hosanna, Southern Ethiopia. Materials and Methods A cross-sectional study was conducted from June 1 to August 30, 2022, involving 209 consecutive pregnant women who came to the hospital during the study period for antenatal care follow-up. Sociodemographic, reproductive, and other clinical data were collected using a structured questionnaire. A four-milliliter venous blood specimen was collected for complete blood analysis and peripheral blood smear. The data were analyzed by using SPSS version 25. Descriptive statistical analysis and bivariate and multivariate logistic regression analyses were performed. A P value ≤0.05 was considered to indicate statistical significance. Results The overall magnitude of thrombocytopenia among pregnant women was 14.8% (95% CI: 10, 19.6). The prevalence of mild, moderate, and severe thrombocytopenia was 77.4%, 16.1%, and 6.5%, respectively. Multivariate logistic regression revealed that rural residence (AOR = 2.6 and 95% CI = 1.02, 7.12), cigarette smoking (AOR = 8.4 and 95% CI = 1.86, 38), anemia (AOR = 8.3 and 95% CI = 2.7, 25.6), and alcohol consumption (AOR = 8.2 and 95% CI = 2.17–31) were significantly independent factors associated with the development of thrombocytopenia. Conclusion The magnitude of thrombocytopenia in this study was 14.8%. Rural residence, cigarette smoking, alcohol consumption, and anemia were significantly associated with thrombocytopenia. Therefore, the platelet count should be routinely determined during antenatal care visits for proper diagnosis and to minimize bleeding during and/or after childbirth.


Introduction
Trombocytopenia is a common hematologic abnormality and is defned as a platelet count less than 150 × 10 9 /L.However, many consider a cutof value of 100 × 10 9 /L to be more appropriate for identifying clinically signifcant thrombocytopenia [1,2].Trombocytopenia is the second most common hematological abnormality during pregnancy after anemia.It occurs in 7-8% of all pregnancies [3,4].
Platelets are anucleate cell fragments of megakaryocytes that play an important role in hemostasis.Tey arise from the fragmentation of megakaryocytes, bone marrow cells with high polyploidy that arise through the process of mitosis and endomitosis [5].After leaving the marrow space, approximately one third of the platelets are sequestered in the spleen, and the remaining two thirds circulate for 7-10 days.Typically, only a small portion of the platelet mass is used in the process of hemostasis, so most platelets circulate until they age and are removed by phagocytic cells.Te normal platelet count is between 150 and 450 × 10 9 /l [6].
Te severity of thrombocytopenia was divided into 3 grades depending on the PLT: mild thrombocytopenia with a PLT between 100 and 150 × 10 9 /l and moderate thrombocytopenia with a PLT between 50 and 100 × 10 9 /l.Severe thrombocytopenia was defned as a level less than 50 × 10 9 /L [5].Te American Society of Hematology requires that treatment be initiated if the PLT is less than 30 × 10 9 /L or if bleeding occurs between the 2nd and 3rd trimesters of pregnancy [4].
Te PLT during pregnancy varies depending on the trimester and gradually decreases from the frst trimester until delivery.Te physiological causes of thrombocytopenia include an increase in plasma volume (dilution efect), accumulation of platelets in the spleen due to spleen enlargement during pregnancy, and accumulation of platelets in the intervillous space of the placenta [7,8].
Trombocytopenia can be caused by decreased bone marrow production, increased splenic sequestration, or accelerated platelet destruction.During pregnancy, most cases are due to increased destruction of platelets, which may be caused by the immune system, abnormal activation of platelets, or consumption of platelets due to exposure to abnormal vessels or excessive bleeding.Reduced platelet production during pregnancy occurs less frequently and is usually associated with bone marrow disorders or nutritional defciencies [1,6].Pregnant women with low platelet counts tend to be much less symptomatic due to the procoagulant state caused by elevated levels of factor VIII, fbrinogen, and von Willebrand factor (VWF); suppressed fbrinolysis; and reduced protein S activity [9].
Trombocytopenia during pregnancy can have various causes.Some of these associations are pregnancy specifc, while others can occur outside of pregnancy.Tese include gestational thrombocytopenia, hypertensive disorders of pregnancy and hemolysis, elevated liver enzymes and low platelet count syndrome (HELLP), liver disease (acute fatty liver of pregnancy), drug-induced thrombocytopenia, immune thrombocytopenic purpura, virus-induced thrombocytopenia, disseminated intravascular coagulation (DIC), hemolytic uremic syndrome (HUS), vitamin B12 and folic acid defciency, and myelopthisis [10,11].
Immune thrombocytopenic purpura (ITP) is caused by platelet autoantibodies against various glycoprotein complexes of the platelet membrane and is responsible for approximately 5% of the cases of thrombocytopenia during pregnancy [12].Pregnant women with hypertension account for 5-21% of the cases of maternal thrombocytopenia [13].Preeclampsia (PE) and HELLP syndrome are considered to be the cause of thrombocytopenia during pregnancy in approximately 14.2% of the cases [12].All pregnant women with a PLT less than 100 × 10 9 /L require detailed hematological and obstetric consultation to rule out more serious conditions [14].In sub-Saharan Africa, the prevalence is slightly higher at 15.3%.Tis condition is responsible for up to 10% of the cases of postpartum hemorrhage in developing countries, with a maternal mortality rate of 5.26% [15,16].
Hematologic changes during pregnancy are common and can result in maternal and fetal morbidity [7].Approximately 8-10% of pregnant women, especially in the third trimester, are afected by thrombocytopenia and 75% of these cases are due to the benign process of gestational thrombocytopenia [17].It is often associated with an increased risk of bleeding before and after birth, particularly during cesarean section or other surgical procedures during pregnancy [4,18].
Te most common cause of gestational thrombocytopenia (GT) is thrombocytopenia during pregnancy, which commonly occurs in 5-11% of pregnant women [19].It is typically an incidental diagnosis, and the pathogenesis of this disease is unclear [20].
Trombocytopenia during pregnancy results in additional, often invasive and unnecessary, examinations and a cesarean section.Pregnant women with thrombocytopenia experience complications such as excessive bleeding during or after delivery, cesarean section discharge, stillbirths, and neonatal thrombocytopenia.Examination and treatment of this condition can be expensive, painful, and potentially undesirable for the patient [18].In Ethiopia, particularly in selected study area complete blood counts are routinely performed for all pregnant women.However, there is no follow-up on platelet count during third trimester, labour, and delivery until severe complications were ensured.Determining magnitude of thrombocytopenia severity and associated factors plays a great role in the management of thrombocytopenic women and is important to develop evidence-based intervention measures, which are not well known in this study area.Terefore, the aim of this study was to evaluate the magnitude of thrombocytopenia and its associated factors during pregnancy at Nigist Ellen Mohammed Memorial Comprehensive Specialized Hospital, Wachemo University.

Study Design, Area, and Period.
A hospital-based crosssectional study was conducted from June 1 to August 30, 2022, at Wachemo University Nigist Ellen Mohammed Memorial Comprehensive Referral Hospital (WUNEMMCSH), which is located in Hosanna Town, Hadiya Zone, Southern Nations Nationalities, and People's Region (SNNPR).Te town is 232 km from the capital city of Addis Ababa to the southwest and 157 km from the regional city of Hawassa.Te town lies on average 2,177 m above the sea level.Tis hospital was established in the 1976 EC, and its catchment area population is estimated to be approximately 3,476,386.On average, 1244 pregnant women attended the hospital annually.Te study was conducted in an antenatal care clinic.

Study Population.
All pregnant women aged between 15 and 49 years who attended the WUNEMCSH antenatal care service clinic during the study period and met the inclusion criteria were included.Study participants who took medications such as heparin and nonsteroidal antiinfammatory drugs such as aspirin and had bleeding 2 Advances in Hematology disorders, splenomegaly, or chronic illness (HCV, HBV, or hypertension) were excluded from the study after reviewing their medical records.

Sample Size Determination and the Sampling Technique.
Te sample size was calculated by using the single population proportion formula by taking the 14.5% prevalence of thrombocytopenia [21] and by considering a 95% confdence interval (CI) and 5% margin of error.Te fnal sample size after adding a 10% nonresponse rate was 209.All pregnant women who attended the WUNEMCSH antenatal care service clinic during the study period were consecutively included in the study until attaining the fnal sample size.

Data Collection Methods and
Instruments.Data on sociodemographic characteristics and clinical and other related factors were collected by trained data collectors.
After the purpose of the study was explained, a laboratory technologist collected 4 mL of venous blood from each study participant into tubes containing ethylenediaminetetraacetic acid (EDTA) for complete blood count analysis and blood smear preparation.Platelet counts, platelet parameters, and other hematological parameters were measured using a MINDRAY BC-3000 PLUS automated hematology analyzer (Shenzhen Mindray Bio-Medical Electronics Co., Ltd., China).Tin blood smears were prepared from thrombocytopenic specimens, air-dried, labeled, and stained with Wright's stain to assess platelet morphology (small platelets and giant platelets) and the presence of malaria parasites.In addition, platelet aggregation was observed to distinguish between pseudo thrombocytopenia and true thrombocytopenia.
Trombocytopenia is said to be present when the platelet count of the pregnant women is less than 150 × 10 9 /L.Te PLT count between 100 and 150 × 10 9 /l is considered mild thrombocytopenia, levels ranging between 50 and 100 × 10 9 /l are considered as moderate thrombocytopenia, and levels less than 50 × 10 9 /L are considered as severe thrombocytopenia [22].

Data Quality Control.
Te quality of the data was guaranteed by implementing quality control (QC) measures throughout the whole process of the laboratory work, data collection, data entry, and data processing.Te quality of the data was maintained by pretesting the questionnaire before the actual data collection.MINDRAY BC-3000 PLUS hematology analyzer was checked for linearity and validity of the results by analyzing whole-blood quality control material (high, normal, and low).Te quality of the blood specimens was maintained during sample collection, transportation, and processing by mixing an appropriate volume of blood and anticoagulant following the standard operating procedure at each step and analyzing the samples within time.All reagents were checked for their expiration date and prepared according to the manufacturer's instructions.Wright stains were fltered every day by using flter paper and stored in locked cabinets away from moisture and sunlight.In addition, thin blood flms prepared from thrombocytopenic clients and stained with Wright stain were examined to confrm the presence of platelet aggregation, which was used to diferentiate true thrombocytopenia from pseudothrombocytopenia.
2.6.Data Processing and Analysis.Te data collected for the study were cleaned, entered into Epi Data version 4.6, and analyzed using the Statistical Package for Social Science (SPSS) version 25 (IBM Corporation, Chicago, USA).Descriptive statistics, frequency tables, graphs, and logistic regression were used to describe the study variables and to determine the impact of the independent variables on the prevalence of thrombocytopenia.Bivariate analysis was performed to select candidate variables for multivariate analysis, and variables with a P value <0.25 were selected as candidates.Multivariate logistic regression analysis was used to identify risk factors associated with thrombocytopenia, 95% confdence intervals were calculated, and a P value of 0.05 or less was used to indicate statistical signifcance.

Ethical Clearance.
Ethical clearance was obtained from the Institutional Review Board (IRB) of the Institute of Health, Jimma University (letter number IRB000843/2022; date, April 30/2022).Permission to conduct the study was obtained from the Wachemo University Nigist Ellen Mohammed Comprehensive Specialized Hospital.All study participants were made aware of the study's purpose, risks, and benefts, and their written informed consent was obtained from each participant before they took part in the study per the Declaration of Helsinki and universal Good Clinical and Laboratory Practice (GCP and GCLP) principles.Patient confdentiality, equity of services, and patient interests were ensured during the study period.All data collected during the study were treated with strict confdentiality and used only for this study.

Sociodemographic Characteristics of the Study
Participants.A total of 209 pregnant women were included in this study with a response rate of 100%.Te mean (±SD) age of the study participants was 26.1 ± 4.983 years (age ranged from 17 to 43).About 61.2% (n � 128) of the study participants were urban area residents.Te majority (85.6%; n � 179) of the participants were married.Among the study participants, about 33.5% (n � 70) were in primary school, and 56.5% (n � 118) were housewives (Table 1).
Tin blood flms were prepared from thrombocytopenic clients, and Wright staining was used to confrm the presence of platelet aggregation, satelitism, and the presence of the malaria parasite.Te commonest blood picture indicates that there was no hemiparasite, platelet aggregation, or platelet satelitism in the blood flm.

Factors Associated with Trombocytopenia in the Study
Participants.According to our bivariate analysis, rural residence, educational status, previous ANC follow-up, history of malaria, eating meat or animal products, smoking cigarette habit, alcohol consumption, hemoglobin level, and middle upper arm circumference (MUAC) were identifed as candidate variables associated with thrombocytopenia multivariate analysis by considering P value <0.25 (Table 3).

Multivariate Logistic Regression Analysis of Factors Associated with Trombocytopenia.
Te variable included in the fnal logistic regression analysis was rural residence; smoking, alcohol consumption, and hemoglobin level were signifcantly associated with thrombocytopenia (Table 4).
Te odds of being were thrombocytopenic approximately 3 times higher among rural residents than among urban residents (AOR � 2.6, 95% CI � 1.02, 7.12, and P � 0.045).Te adjusted odds ratio (OR) revealed that pregnant women who smoked cigarettes were 8 times more likely to be

Discussion
Trombocytopenia during pregnancy afects about 1 in 10 pregnant women worldwide.Te rate of thrombocytopenia in pregnant women is 4 times greater than that in nonpregnant women.Terefore, timely diagnostic, preventive, and therapeutic measures are necessary for the efective management of thrombocytopenia during pregnancy [23].
Trombocytopenia is the second most common hematologic disorder in the world and afects 7-10% of all pregnancies.Tis condition is responsible for up to 10% of postpartum hemorrhages in developing countries, for which the maternal mortality rate is 5.26% [15,16].Te present study attempted to evaluate the magnitude of thrombocytopenia, severity patterns, and associated factors in pregnant women at Wachemo University Nigist Ellen Mohammed Memorial Compressive Specialized Hospital in southern Ethiopia.Our fndings showed a 14.8% (95% CI: 10, 19.6) overall magnitude of thrombocytopenia among pregnant women; out of them, 24 (77.4%), 5 (16.1%), and 2 (6.5%) had mild, moderate, and severe thrombocytopenia, respectively.
A systematic review and meta-analysis of global thrombocytopenia showed that the prevalence of thrombocytopenia is four times greater in pregnant women than in nonpregnant women [23]; the average global prevalence was 8.4% (CI: 6.9-10.1%)[23].However, our study fnding was higher than the global prevalence of thrombocytopenia.Terefore, these fndings provide assurance or confrmation that routine screening and follow-up programs are needed to identify pregnant women with thrombocytopenia and ofer them essential interventions.
Hematological changes during pregnancy are common and can lead to maternal and fetal morbidity, especially in the third trimester, when the condition is afected by thrombocytopenia.Tere are many causes of thrombocytopenia during pregnancy, ranging from mild to lifethreatening, and thrombocytopenia needs to be diagnosed and treated promptly [7,17].Te severity patterns among the thrombocytopenic pregnant women in our study were 77.4%, 16.1%, and 6.5% in mild, moderate, and severe thrombocytopenia, respectively.Tese fndings are consistent with studies conducted in Ethiopia, Libya, India, Uganda, and Ghana [3,15,19,26,31,33,34], which indicate a high frequency of mild thrombocytopenia.
Several studies have reported that the prevalence of thrombocytopenia is signifcantly afected by diferent sociodemographic characteristics [18,21,29].In the present study, thrombocytopenia was signifcantly associated with rural residence.Tese fndings are in agreement with those of studies performed in Ethiopia [33,34] and Libya [31].Tis might be related to a lack of information about adequate nutrition, lack of information on factors causing thrombocytopenia and possible strategies to prevent risk factors, inaccessibility of health care centers to ANC follow-up, and way of life.
Alcoholism is one of the most serious socioeconomic health problems in the world [35].According to the current study, pregnant women with a habit of alcohol consumption were 8 times more likely to develop thrombocytopenia than their counterparts were.Tis fnding was in line with a study in Ethiopia in which the habit of alcohol consumption was more likely to lead to thrombocytopenia [21].Te possible explanations that explain these associations might be the direct toxic efect of alcohol on the suppression of blood cell production, hematopoiesis, impaired function, and a decreased platelet life span [33,35,36].
Cigarette smoking can induce both acute and chronic efects on platelet function.Smoking induces oxidative stress, leading to increased platelet activation and aggregation and endothelial injury [37].Te present study Advances in Hematology revealed that there was a statistically signifcant association between thrombocytopenia and smoking cigarettes.Smoking cigarettes were associated with 8.4 times greater odds of thrombocytopenia than nonsmoking cigarettes were.A possible explanation might be that cigarette smoke induces oxidative stress, damages endothelial tissue, and disturbs the function of platelets, especially through activation and aggregation, as well as other coagulation components, leading to thrombosis [34,37,38].Anemia during pregnancy was strongly associated with thrombocytopenia in this study.Te odds of having thrombocytopenia were eight times higher among women with an Hb concentration less than 11 g/dl compared to those who had hemoglobin ≥11 g/dl, which are signifcant (A0R: 7.7 and 95% CI: 2.8-21.6).Tis fnding was similar to that of a study performed in Uganda and Ethiopia, where a strong association between anemia and thrombocytopenia was observed [15,39].Recurrent thrombocytopenia has typically been linked to iron defciency anemia, which is prevalent throughout pregnancy.Te dual role of iron in the creation of platelets, which is necessary for the production of an integral section of the platelet, and the diphasic response of platelets to erythropoietin are the hypothesized causes of thrombocytopenia in patients with IDA [40].Te fndings of our study should be concluded in light of some limitations.First, the cross-sectional nature of the study design prohibited the establishment of causal links between thrombocytopenia and factors that are signifcantly associated with thrombocytopenia.Second, the duration of alcohol consumption per day, type of alcohol, and alcohol concentration among the study participants were not assessed.Tird, data on cigarette smoking concerning the number smoked per day and the type of cigarettes smoked were not assessed among the study participants.

Conclusion
A greater magnitude of thrombocytopenia (14.8%) was observed among pregnant women.Among the thrombocytopenic pregnant women, mild thrombocytopenia was the predominant condition in our study.Rural residence, alcohol consumption, cigarette [41] smoking, and anemia were identifed as independent predictors of thrombocytopenia among pregnant women.Terefore, screening should include platelet counts, especially when the woman is from a rural residence, is anemic, consumes alcohol, or is a cigarette smoker, to avoid adverse outcomes.

Table 1 :
Sociodemographic characteristics of pregnant women attending antenatal care clinics at Wachemo University Nigist Ellen Mohammed Comprehensive Specialized Hospital Hosanna, Southern Ethiopia, from June toAugust 30, 2022.

Table 2 :
Reproductive, clinical, and other related characteristics of pregnant women attending antenatal care clinics at Wachemo University Nigist Ellen Mohammed Comprehensive Specialized Hospital Hosanna, Southern Ethiopia, from June toAugust 30, 2022.

Table 3 :
Bivariate analysis of factors associated with thrombocytopenia among pregnant women attending antenatal care clinics at Wachemo University Nigist Ellen Mohammed Comprehensive Specialized Hospital Hosanna, Southern Ethiopia, from June to August 30, 2022.

Table 4 :
Multivariate logistic regressions of selected factors associated with thrombocytopenia among pregnant women attending antenatal care clinics at Wachemo University Nigist Ellen Mohammed Comprehensive Specialized Hospital Hosanna, Southern Ethiopia, from June toAugust 30, 2022.