Pregnant women are being warned that unless they are anaemic, say doctors, extra iron could cause her to develop high blood pressure, which in turn may lead to her baby being born smaller.
The study, by researchers at Tarbiat Modares University in Tehran and published in BJOG: An International Journal of Obstetrics and Gynaecology, examined 727 women who had normal levels of iron in their blood.
It found women taking iron supplements during pregnancy were more likely to develop high blood pressure and to have a baby that was small for its gestational age.
Professor Philip Steer, the journal’s editor-in-chief, said: “Anaemia in women is often associated with low birth weight and pre-term births but that does not mean women should be popping iron pills, or any vitamin pills indiscriminately, to prevent poor pregnancy outcomes.
“Women should ensure that they receive proper advice on diet and nutrition from their doctors.”
Robert Fraser, spokesman for the charity WellBeing of Women, who specialises in nutrition in pregnancy at Sheffield University, said: ‘In many developing countries a substantial proportion of pregnant women are iron-deficient. But in countries like Britain most people are not anaemic.
“Routine supplementation was recommended 25 years ago, which is why mothers often ask their pregnant daughters why they’re not taking iron tablets.
“But the majority of women don’t need to unless they have been told there is a specific reason.”
Pregnant women who are suffering stress ‘transmit’ the effect to their unborn child as early as 17 weeks, scientists have discovered.
They have matched the level of stress hormones found in the mother’s blood to those in the amniotic fluid surrounding the foetus. It is the first time the link has been established at such an early stage in pregnancy.
Previous research already suggests stress hormones have an effect on foetal brain development and a child’s future behaviour.
The research, led by Professor Vivette Glover at Imperial College London, and Dr Pampa Sarkar, of Wexham Park Hospital in Berkshire, took samples of blood and amniotic fluid from 267 pregnant women.
In both samples, levels of the stress hormone cortisol were found, acording to the report, published today in the journal Clinical Endocrinology.
Previous research has already found babies exposed to high levels of the hormone in the womb had lower IQs at 18 months than other children of the same age.
It also doubles the risk of a child developing hyperactivity and Attention Deficit Hyperactivity Disorder by the age of four.
I was warned against taking ‘elemental’ iron while I was pregnant by my homeopathic doctor. If you must take iron while pregnant he recommended liquid iron, which can be mixed into smoothies or juice, by floradix.
Please check with your doctor before taking anything while you are pregnant. He/she will be able to tell you if such substances will harm your baby.