Anaemia in pregnancy remains a global health problem
In this issue of BJOG Hull et al …… et al report on
an important study from South Africa regarding anaemia in pregnancy and
the response to iron therapy. They report that in HIV-positive women the
response was slower than in HIV-negative women. The underlying causes of
anaemia varied and included iron deficiency (as assessed by ferritin
levels) as well as concurrent infections (urinary tract infections and
tuberculosis)
Anaemia in pregnancy (blood haemoglobin Hb<11.0g/dl) occurs in
> 40% of women living in low- and middle-income countries
(LMIC) and in some settings in Asia prevalence is >60%.
(McCauley et al, BMJ Global Health, 2018; 3(3):e000625) The
latest WHO recommendations on antenatal care consider anaemia as the
world’s second leading cause of disability and one of the most serious
global public health problems (WHO Geneva 2016 ) .
Although globally the focus has largely been on anaemia in pregnancy
resulting from either iron deficiency or malaria, this is an incomplete
approach at best. Iron deficiency is hard to measure and confirm as; i)
this requires a functioning laboratory to be in place, ii) indicators
for iron deficiency are influenced by the presence of concurrent
infection, or, iii) repeated measures of Hb are needed to check whether
the anaemia is responsive to treatment with iron. By contrast, malaria
is relatively easy to diagnose via rapid diagnostic tests or microscopic
examination of a stained blood smear slide. The handful of studies which
have comprehensively assessed aetiology of anaemia in pregnant women
demonstrate that anaemia is most commonly the result of complex multiple
underlying factors including nutritional deficiencies as well as
infectious diseases. Both nutritional deficiency and other infections
(malaria, tuberculosis) are more likely with HIV-infection which itself
can lead to anaemia probably through direct suppression of
erythropoiesis.
Hull et al show what was possible in a real-life clinical
practice setting. This example of integration of research into clinical
practice is laudable and is illustrative of how such integration could
result in better services being made available for women in LMIC where
burden of disease is high, but diagnostic tests are largely unavailable.
It is sobering to realise that the majority of women world-wide will
still only be screened for anaemia during pregnancy using ‘conjunctival
inspection’ which is highly inaccurate. (van den Broek et al. Bull
WHO 1999; 77(1):15-21) Rapid diagnostic tests are available for Hb,
malaria, syphilis, HIV and, more recently, for tuberculosis. We are
doing women a dis-service if we cannot offer at least these basic
diagnostic tests as part of antenatal care.
To prevent anaemia during pregnancy, the ‘fall-back’ position is to
offer all women daily iron prophylaxis (30-60mg elemental iron) - with
luck tablets are available that include folic acid (0.4mg) - along with
presumptive treatment of malaria (various regimes) in endemic areas.
Multi-micronutrients (including the required amount of iron and folic
acid) might actually be better but cannot be recommended because of lack
of evidence and they are still three times as expensive as iron and
folic acid supplementation alone (3$ vs 1$ approximately).
WHO recently recommended a better understanding of the aetiology of
anaemia. A search on PubMed shows a clear lack of papers on the topic
and more good research is needed. Investment in the antenatal care
package offered to women is also much needed if we are aiming for a
global ‘Health for All’.