Featured Research

from universities, journals, and other organizations

Month of birth effect: Give pregnant women vitamin D supplements to ward off multiple sclerosis, say researchers

Date:
November 14, 2012
Source:
BMJ-British Medical Journal
Summary:
The risk of developing multiple sclerosis is highest in the month of April, and lowest in October, indicates an analysis of the available evidence, published online in the Journal of Neurology Neurosurgery and Psychiatry.

The risk of developing multiple sclerosis (MS) is highest in the month of April, and lowest in October, indicates an analysis of the available evidence, published online in the Journal of Neurology Neurosurgery and Psychiatry.

The findings, which include several populations at latitudes greater than 52 degrees from the equator for the first time, strongly implicate maternal exposure to vitamin D during pregnancy.

They extend previous research and prompt the authors to conclude that there is now a strong case for vitamin D supplementation of pregnant women in countries where ultraviolet light levels are low between October and March.

The researchers compared previously published data on almost 152,000 people with MS with expected birth rates for the disease in bid to find out if there was any link between country of birth and risk of developing multiple sclerosis.

At latitudes greater than 52 degrees from the equator, insufficient ultraviolet light of the correct wavelength (290 to 315 nm) reaches the skin between October and March to enable the body to manufacture enough vitamin D during the winter months, say the authors.

The analysis indicated a significant excess risk of 5% among those born in April compared with what would be expected. Similarly, the risk of MS was 5 to 7% lower among those born between October and November, the data indicated.

In order to exclude wholly or partially overlapping data, and therefore the potential to skew the data, the authors carried out a further "conservative analysis" in which such studies were left out.

This reduced the number of people with MS to just under 78,500 and showed a clear link only between November and a reduced risk of MS.

But this result is likely to have been due to the fact that all the excluded studies involved countries more than 52 degrees from the equator, explain the authors.

When the same analysis was carried out again, but this time including all those involving people living in countries less than 52 degrees from the equator, the same seasonal trends were apparent.

There was a significant increase in risk among those born in April and May and a significantly lower risk among those born in October and November.

No studies from the southern hemisphere were included in the analysis, largely because so few have been carried out, so the results should be viewed in light of that, caution the authors.

But they conclude: "Through combining existing datasets for month of birth and subsequent MS risk, this study provides the most robust evidence to date that the month of birth effect is a genuine one."

And they go on to say: "This finding, which supports concepts hypothesised some years previously, surely adds weight to the argument for early intervention studies to prevent MS through vitamin D supplementation."


Story Source:

The above story is based on materials provided by BMJ-British Medical Journal. Note: Materials may be edited for content and length.


Journal Reference:

  1. R. Dobson, G. Giovannoni, S. Ramagopalan. The month of birth effect in multiple sclerosis: systematic review, meta-analysis and effect of latitude. Journal of Neurology, Neurosurgery & Psychiatry, 2012; DOI: 10.1136/jnnp-2012-303934

Cite This Page:

BMJ-British Medical Journal. "Month of birth effect: Give pregnant women vitamin D supplements to ward off multiple sclerosis, say researchers." ScienceDaily. ScienceDaily, 14 November 2012. <www.sciencedaily.com/releases/2012/11/121114192615.htm>.
BMJ-British Medical Journal. (2012, November 14). Month of birth effect: Give pregnant women vitamin D supplements to ward off multiple sclerosis, say researchers. ScienceDaily. Retrieved September 17, 2014 from www.sciencedaily.com/releases/2012/11/121114192615.htm
BMJ-British Medical Journal. "Month of birth effect: Give pregnant women vitamin D supplements to ward off multiple sclerosis, say researchers." ScienceDaily. www.sciencedaily.com/releases/2012/11/121114192615.htm (accessed September 17, 2014).

Share This



More Health & Medicine News

Wednesday, September 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

President To Send 3,000 Military Personnel To Fight Ebola

President To Send 3,000 Military Personnel To Fight Ebola

Newsy (Sep. 16, 2014) President Obama is expected to send 3,000 troops to West Africa as part of the effort to contain Ebola's spread. Video provided by Newsy
Powered by NewsLook.com
Obama Orders Military Response to Ebola

Obama Orders Military Response to Ebola

AP (Sep. 16, 2014) Calling the Ebola outbreak in West Africa a potential threat to global security, President Barack Obama is ordering 3,000 U.S. military personnel to the stricken region amid worries that the outbreak is spiraling out of control. (Sept. 16) Video provided by AP
Powered by NewsLook.com
UN: 20,000 Could Be Infected With Ebola by Year End

UN: 20,000 Could Be Infected With Ebola by Year End

AFP (Sep. 16, 2014) Nearly $1.0 billion dollars is needed to fight the Ebola outbreak raging in west Africa, the United Nations say, warning that 20,000 could be infected by year end. Duration: 00:40 Video provided by AFP
Powered by NewsLook.com
Obama: Ebola Outbreak Threat to Global Security

Obama: Ebola Outbreak Threat to Global Security

AP (Sep. 16, 2014) President Obama is ordering U.S. military personnel to West Africa to deal with the Ebola outbreak, which is he calls a potential threat to global security. (Sept. 16) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

    Technology News



    Save/Print:
    Share:

    Free Subscriptions


    Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

    Get Social & Mobile


    Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

    Have Feedback?


    Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
    Mobile: iPhone Android Web
    Follow: Facebook Twitter Google+
    Subscribe: RSS Feeds Email Newsletters
    Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins