Clinical trial NCT05929326: Reference Intervals of Complete Blood Count and Coagulation Tests in Pregnant Women at Hung Vuong Hospital
Official title: Establishment of Reference Intervals of Complete Blood Count and Coagulation Tests in Pregnant Women at Hung Vuong Hospital
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Pregnancy Related
Keywords: Reference intervals
pregnancy
complete blood count
coagulation tests
Lead sponsor: Hung Vuong Hospital
Sponsor class: OTHER
Collaborators: name: MITALAB COMPANY LIMITED
First posted: 2023-07-03
Enrollment: 879
Sex: FEMALE
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: CASE_ONLY
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: pregnant women at obstetrics clinics at Hung Vuong Hospital

Brief summary: Rationale: Pregnancy has major effects on physiology in women. There have been many studies that established reference intervals but none was done in Vietnam. The recommendation by CLSI C28-A3 is that if possible, each laboratory establishes its own reference intervals.

Objective: To establish the reference intervals of complete blood count parameters and Prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen.

Study design: This is a cross-sectional study.

Study population: Pregnant women with no history of disease and normal clinical findings.

Detailed description: Reference intervals (RI) is defined as the central 95% interval of the distribution of values taken from a biological reference population. RI is established for each trimester. The sample needed for each trimester is at least 258 which adds up to 774 when combining three trimesters.

Pregnant women are selected if eligible from obstetrics clinics after history taking and clinical findings. After consent, their blood are then drawn by phlebotomist into an ethylenediamine tetraacetic acid (EDTA) and a trisodium citrate 3.2% blood tube. EDTA samples are run on DxH 900 hematology analyzer, manufactured by Beckman Coulter and citrate samples are run on ACL TOP 550 coagulation analyzer, manufactured by Werfen. The analyzers are verified by laboratory procedure, recommended by Clinical and Laboratory Standards Institute (CLSI) method and quality control is checked before in accordance to the laboratory procedure.

Statistical analysis: Patients were divided into three groups, which are first, second, and third trimester. CLSI EP28-A3c recommended Dixon's D/R ratio outlier test to exclude outliers, where D is the absolute difference between the largest (or smallest) and the second largest (or smallest) observation, and R is the range of all observations. If D is equal to or greater than one-third of R, that observation is considered an outlier and is deleted. After outliers were deleted, the remaining data was tested again for additional outliers until there were no more outliers. A non-parametric method, recommended to establish reference intervals by CLSI EP28-A3c, was used to determine the lower reference limit 2.5th percentile and upper reference limit 97.5th percentile for each group.

Each reference limit was reported along with its 90th confidence interval. Groups were then compared using normal approximation with continuous correction Mann-Whitney U. A two-tailed P-value \< 0.05 was considered significant. Statistical analysis was performed using NCSS statistical software (Utah, USA) version 2023

Eligibility criteria: Inclusion Criteria:

* Singleton Pregnancy

Exclusion Criteria:

* Hypertension, Diabetes, Preeclampsia, Gestational Diabetes, Hemoglobinopathy, Current Infection, Positive Screening for Treponema pallidum, Hepatitis B Virus, HIV, usage of anticoagulant drug.

Primary outcomes:
measure: Trimester Specific Prothrombin Time Reference Interval
timeFrame: Each participant's blood samples are run immediately after phlebotomy within 30 minutes
measure: Trimester Specific Activated Partial Thromboplastin Time Reference Interval
timeFrame: Each participant's blood samples are run immediately after phlebotomy within 30 minutes
measure: Trimester Specific Fibrinogen Reference Interval
timeFrame: Each participant's blood samples are run immediately after phlebotomy within 30 minutes
measure: Trimester Specific Hemoglobin Reference Interval
timeFrame: Each participant's blood samples are run immediately after phlebotomy within 30 minutes
measure: Trimester Specific Red Blood Cell Count Reference Interval
timeFrame: Each participant's blood samples are run immediately after phlebotomy within 30 minutes
measure: Trimester Specific White Blood Cell Count Reference Interval
timeFrame: Each participant's blood samples are run immediately after phlebotomy within 30 minutes
measure: Trimester Specific Hematocrit Reference Interval
timeFrame: Each participant's blood samples are run immediately after phlebotomy within 30 minutes
measure: Trimester Specific Platelet Reference Interval
timeFrame: Each participant's blood samples are run immediately after phlebotomy within 30 minutes
Secondary outcomes:
Other outcomes:
Locations:
city: Ho Chi Minh
country: Vietnam
facility: Hung Vuong Hospital
Study officials:
affiliation: Hung Vuong Hospital
name: Huan N Pham, Doctor
role: PRINCIPAL_INVESTIGATOR
References:
citation: de Haas S, Ghossein-Doha C, van Kuijk SM, van Drongelen J, Spaanderman ME. Physiological adaptation of maternal plasma volume during pregnancy: a systematic review and meta-analysis. Ultrasound Obstet Gynecol. 2017 Feb;49(2):177-187. doi: 10.1002/uog.17360.
citation: Gong JM, Shen Y, He YX. Reference Intervals of Routine Coagulation Assays During the Pregnancy and Puerperium Period. J Clin Lab Anal. 2016 Nov;30(6):912-917. doi: 10.1002/jcla.21956. Epub 2016 Apr 7.
citation: Jin Y, Lu J, Jin H, Fei C, Xie X, Zhang J. Reference intervals for biochemical, haemostatic and haematological parameters in healthy Chinese women during early and late pregnancy. Clin Chem Lab Med. 2018 May 24;56(6):973-979. doi: 10.1515/cclm-2017-0804.
citation: Cui C, Yang S, Zhang J, Wang G, Huang S, Li A, Zhang Y, Qiao R. Trimester-specific coagulation and anticoagulation reference intervals for healthy pregnancy. Thromb Res. 2017 Aug;156:82-86. doi: 10.1016/j.thromres.2017.05.021. Epub 2017 May 24.