Taking vitamin D supplements could help women conceive, research suggests.
Experts at Birmingham University found women undergoing fertility treatment were 33 per cent more likely to have a baby if their vitamin D levels were healthy.
They said the findings may explain why people tend to find it easier to conceive in the summer, when vitamin D levels are boosted by the sun’s rays.
The NHS already recommends women who are pregnant or trying to conceive take daily vitamin D supplements for the sake of the development of their baby.
But the new findings, published in the Human Reproduction journal, suggests it also might help them conceive in the first place.
Taking vitamin D supplements could help women conceive, research suggests
VITAMIN D IN CHILDHOOD PREVENTS TYPE 1 DIABETES BY BOOSTING THE IMMUNE SYSTEM
Vitamin D in childhood prevents type 1 diabetes, research suggested last month.
The sunshine supplement lowers susceptible individuals’ risk by strengthening their immune system, a study found.
Lead author Dr Jill Norris from the University of Colorado, said: ‘For several years there has been controversy among scientists about whether vitamin D lowers the risk of developing type 1 diabetes.’
Type 1 diabetes is an autoimmune condition that occurs when a person’s immune system attacks the cells that produce insulin.
The condition is increasing by three-to-five percent annually, particularly among children.
It is on the rise too quickly to be the fault of genetics, with experts therefore blaming everything from gluten, a growing obsession with cleanliness and obesity for the disorder’s surging numbers.
Only 26% of women have sufficient vitamin D levels
Crucially, they found three in four women trying for a baby were deficient in vitamin D.
The researchers examined the records of 2,700 women undergoing IVF and other forms of fertility treatment.
Their data – compiled from 11 previous studies – suggested women who had sufficient levels of vitamin D in their blood were 46 per cent more likely to become pregnant and 33 per cent more likely to have a live birth.
The scientists said it was likely similar results would be found among those attempting to conceive naturally.
Researcher Dr Ioannis Gallos, a reproductive specialist in Birmingham, stressed they had only found a link connected to blood tests – and had not actually tested whether supplements would boost fertility.
He called for a full randomised control trial to establish whether vitamin D can indeed improve the chances of conceiving.
But he said: ‘Women should follow the national guidance on this and take a low-dose vitamin D supplement. And if they are concerned they are deficient they can get tested.’
He added: ‘One startling finding was the high prevalence of vitamin D deficiency among these women.
‘We found that only 26 per cent of women in the studies had sufficient concentrations of vitamin D.’
Vitamin D may dampen inflammation
The researchers believe vitamin D may help dampen the immune system’s inflammatory response, improving the chances that an embryo successfully implants in the lining of the womb at the very start of pregnancy.
They wrote: ‘Seasonal variations in conception rates have been established with higher conception rates found in the summer and autumn.
‘Although many hypotheses have been postulated to explain this phenomenon the exact mechanism behind this has not been explained.
‘It is possible that an increase in sun exposure and greater sunlight luminosity increases the body’s store of vitamin D, thereby yielding higher conception rates in summer and autumn.’
Vitamin D may dampen inflammation, allowing embryos to successfully implant in the womb
Sunshine supplement boosts babies’ bone growth
Vitamin D is produced naturally by the skin when it soaks up the sun’s rays – but experts are worried Britain’s poor weather and modern indoor lifestyles mean we are not getting enough sunlight.
Oily fish such as sardines or mackerel, red meat, liver or eggs are all rich in vitamin D.
But fewer people are now eating these foods, and one in five people in Britain now have low levels of the vitamin D.
The vitamin is particularly important during pregnancy, and is already known to affect the way a baby’s bones grow in the womb.
But very few women trying for a baby actually follow NHS advice to take a supplement.
Government advisors last year extended the guidelines to suggest that all adults – not just pregnant women – should consider taking vitamin D supplements over the winter, to avoid bone diseases such as rickets.
Fellow researcher Dr Justin Chu said women should beware taking very high doses of vitamin D in a bid to conceive – as it is possible to overdose.
The NHS recommended dose of 10 micrograms a day is considered to be safe.
But Dr Chu said women should beware taking more than this without medical advice, adding: ‘It is possible to overdose on vitamin D and this can lead to too much calcium building up in the body, which can weaken bones and damage the heart and kidneys.
‘Testing for vitamin D concentrations is relatively cheap and widely available and its treatment is not costly.
‘It could be that correcting vitamin D deficiency could benefit women undergoing assisted reproduction treatment, but further research is needed to test this.’