Pakistan Journal of Nutrition 15 (6): 585-589, 2016
ISSN 1680-5194
© Asian Network for Scientific Information, 2016
Corresponding Author: M.A. Emokpae, Department of Medical Laboratory Science, School of Basic Medical Sciences, University of
Benin, Benin City, Nigeria
585
Levels of Some Essential Elements in Pregnant Women and
Association with Low Birth Weight of Babies in Benin City
Osaretin James Agbonlahor and Mathias Abiodun Emokpae
1 2
Department of Medical Laboratory Services, Stella Obasanjo Hospital, Benin City, Nigeria
1
Department of Medical Laboratory Science, School of Basic Medical Sciences,
2
University of Benin, Benin City, Nigeria
Abstract: Poor foetal growth and development has been associated with maternal inadequate or under-
nutrition. There is no agreement as to whether dietary macro and micro-nutrient supplementation in
pregnancy enhance neonatal birth weight. This study evaluates the levels of magnesium, calcium, albumin
and phosphorus in pregnant women at delivery, the proportion of the neonates with low birth weight and the
relationship between these essential elements and neonatal birth weight. A total of 300 subjects were
enrolled, which included 200 healthy pregnant women and 100 age-matched non-pregnant women
(controls). The concentrations of essential elements in maternal blood were measured using Atomic
Absorption Spectrophotometry and colorimetric methods. The concentrations of magnesium and albumin
were significantly (p<0.001) higher in women who had babies with low birth weight than those had normal
birth weight. Conversely, calcium (p = 0.002) and phosphorus (p<0.001) levels were significantly lower in
women who had babies with low birth weight compared with those that had babies with normal birth weight.
The levels of measured variables in the pregnant women at delivery were significantly lower (p<0.001)
compared with controls. Supplementation of some of these essential elements may help to prevent the
delivery of infants with low birth weight. Therefore measurement of these essential elements may be
considered important as part of the routine antenatal investigations.
Key words: Pregnant women, essential elements, infants and low birth weight
INTRODUCTION
It is universally accepted that adequate nutrition before
and during pregnancy could greatly affect the health of
both mother and infants (Singh et al., 2009). A well
nourished women before conception begins her
pregnancy with reserved of essential nutrients such that
the growth and well being of the growing foetus and
good health of the women is achieved. A neonate who
was well nourished in the womb stands a better chance
of becoming healthy after birth than that who was
malnourished. Poor foetal growth and development has
been associated with maternal inadequate or under-
nutrition (Khoushabi and Saraswathi, 2010). There is no
agreement as to whether dietary macro and micro-
nutrient supplementation in pregnancy enhance
neonatal birth weight (Muthayya, 2009). However, it was
suggested that nutritional deficiency may be responsible
for up to 60% of the reported variations in birth weight. It
also observed that high intake of calcium, magnesium,
iron and zinc significantly affect the birth weight of infants
(Khoushabi and Saraswathi, 2010). The prevalence of
low birth weight (LBW) varies from one region to another
and the estimated prevalence is particularly high in
developing countries. The prevalence of 15-30% was
reported in India (Kapil, 2009), Sri Lanka, Nepal and
UNICEF/WHO estimated figure for Sub-Sahara Africa
(Mavalankar et al., 1992; UNICEF and WHO, 2004). The
Nigerian Demographic Health Survey put the incidence
of LBW as 14% (655 per 1000) (NPC and ORC Macro,
2009).
Magnesium, calcium, phosphorus and albumin are
essential elements of nutrition required for cell
multiplication in a growing fetus, proper soft tissue
functioning during muscle contraction, bone formation in
fetus, hormone release and other physiological actions
(Mariko et al., 2011). The demand for these essential
elements is higher during pregnancy. Therefore, a
pregnant woman requires more of these nutrients
(calcium, magnesium, phosphorus and albumin) than
a non-pregnant woman (Baig et al., 2003). Previous
studies on the association of these essential elements
with neonatal birth weight and thus the need for
supplementation during pregnancy had yielded
inconsistent results. Some of them reported that LBW
was associated with low levels of calcium, magnesium,
phosphorus and albumin in maternal blood (Baba et al.,
2012; Mariko et al., 2011; Merialdi et al., 2003; Baig et al.,
2003; Stephenson and Symonds, 2002). Others did not
find any association of these elements with infant birth
weight (Pourarian et al., 2014; Pathak and Kapil, 2004).
In Nigeria, Baba et al. (2012) examined the correlation of