Determining Significant Predictors of Blood Iron Concentration and Status in Pregnant Filipino Women Using Linear Models

Vanessa Joy A. Timoteo1,3*, Leslie Michelle M. Dalmacio2, Jacus S. Nacis1,
Juanita M. Marcos1, Rod Erick L. Agarrado1, and Mario V. Capanzana1

1Food and Nutrition Research Institute, Department of Science and Technology,
DOST Complex, Bicutan, Taguig City 1631 Philippines
2Department of Biochemistry and Molecular Biology, College of Medicine,
University of the Philippines Manila, 547 Pedro Gil St., Ermita, Manila 1000 Philippines
3Taiwan International Graduate Program in Molecular Medicine,
National Yang-Ming University and Institute of Biomedical Sciences, Academia Sinica,
No. 128, Sec. 2, Academia Rd., Nangang District, Taipei City 115 Taiwan (R.O.C.)


*Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.



The decrease in blood iron levels during pregnancy is a concern that needs to be addressed, especially among Filipinos where anemia prevalence is relatively high. This study assessed maternal age, gestational age, height, body weight during pregnancy, daily consumption of iron supplements or multivitamins, gravidity, parity, and estimated monthly household income as potential predictors of levels of hemoglobin (Hb), hematocrit (Hct), serum ferritin (SF), serum iron (SI), total iron binding capacity (TIBC), unsaturated iron binding capacity (UIBC), and transferrin saturation (TSAT) among 109 pregnant women residing in Quezon, Palawan using simple linear regression (SLR). Significant predictors were then incorporated into full models using multiple linear regression (MLR) following the hierarchical method. Results show that gestational age significantly contributed to predicting levels of blood iron (p < 0.05). Gestational age was negatively associated with Hb, Hct, SF, log10 SF, log10 SI, and TSAT but positively associated with TIBC and UIBC. Gestational age accounted for variations ranging from as low as 4% in log10 SI up to 35% in UIBC. Additionally, weight was positively associated with Hb (p = 0.016) and Hct (p = 0.027), parity was negatively associated with log10 SF (p = 0.031), and daily consumption of iron or multivitamin supplements was negatively associated with TIBC (p < 0.001) and UIBC (p < 0.001). These identified predictors can be used in the clinical settings to target high-risk women for treatment or intervention.


The public health impact of anemia due to iron deficiency is often highlighted in its implications for obstetrics and perinatal care. Iron deficiency anemia (IDA) accounts for 75% of all types of anemia that occur during pregnancy (Horowitz et al. 2013), and pregnant women are among the high-risk groups due to the competition on iron demands between the mother and her developing fetus (NHLBI 2014; WHO 2017a). This demand for iron can also be aggravated by other related conditions such as uterine or placental bleedings, gastrointestinal bleedings, and peripartum blood loss (Breymann 2015). IDA poses an increase in the risk of preterm delivery, perinatal mortality, low birth weight, neonatal mortality, lactation failure, and postpartum depression, among others (Abu-Ouf & Jan 2015; Di Renzo et al. 2015). This premise prompted the public health experts to require approximately 1,000–1,200 mg of iron throughout the course of pregnancy, which should be met through a balance between daily iron intake and inherent iron stores in the body of a pregnant woman (Brannon & Taylor 2017). . . . read more



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