Featured Research

from universities, journals, and other organizations

New Test Could Cut Unnecessary Treatment For Blood Disorder In Pregnancy

Date:
April 8, 2008
Source:
BMJ-British Medical Journal
Summary:
A new test for identifying a mismatch between the blood of a pregnant woman and her baby is accurate, feasible, and could substantially reduce unnecessary treatment, finds a new study.

A new test for identifying a mismatch between the blood of a pregnant woman and her baby is accurate, feasible, and could substantially reduce unnecessary treatment, finds a study published on the British Medical Journal website.

Related Articles


Problems can occur if a woman's blood is Rhesus (Rh) negative but she is carrying a baby whose blood is Rh positive. This is because Rh positive blood contains a substance called RhD antigen, which passes into the mother's blood at birth. The mother then makes antibodies against the RhD positive blood.

There are usually no problems during a woman's first pregnancy, but if she goes on to have another RhD positive baby, these antibodies cross the placenta and destroy the baby's red blood cells, causing a blood disorder known as haemolytic disease that can be serious and even fatal.

To prevent this, all pregnant women have their blood tested at their first antenatal visit. RhD negative women are given one or two antiserum injections (anti-RhD immunoglobulin, derived from blood products) during the pregnancy.

However, about 38% of RhD negative women are carrying an RhD negative baby, so they receive this treatment unnecessarily.

So researchers at the NHS Blood and Transplant Centre in Bristol assessed a new test for predicting a baby's blood group by "typing" its DNA in the plasma of RhD negative pregnant women.

They analysed blood samples from 1,997 women taken at or before the 28 week antenatal visit. In 96% of cases, the correct RhD phenotype of the baby was predicted by the genotyping tests. This was confirmed by comparing the results obtained from cord blood samples taken at delivery.

A false positive result was obtained in 0.8% (14 samples), and in only three samples (0.2%) were false negative results obtained.

In 3.4% of cases results were either unobtainable or inconclusive.

If these results had been applied as a guide to treatment, only 2% of the women would have received anti-RhD unnecessarily, compared with 36% without genotyping.

The results show that fetuses of RhD negative women can be genotyped with an acceptable level of accuracy and a low rate of false positive results, say the authors. Testing would avoid unnecessary treatment in about 38% of RhD negative women and avert the associated discomfort, inconvenience, and risk of exposure to donor blood products that such injections entail, they conclude.

These findings are important because they demonstrate the reliability of the automated technique and the feasibility of large scale antenatal testing, writes Sailesh Kumar from Queen Charlotte's and Chelsea Hospital in an accompanying editorial.

He concludes: "If these techniques are shown to be as reliable earlier in pregnancy the arguments for recommending universal testing will be compelling."


Story Source:

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


Cite This Page:

BMJ-British Medical Journal. "New Test Could Cut Unnecessary Treatment For Blood Disorder In Pregnancy." ScienceDaily. ScienceDaily, 8 April 2008. <www.sciencedaily.com/releases/2008/04/080403202738.htm>.
BMJ-British Medical Journal. (2008, April 8). New Test Could Cut Unnecessary Treatment For Blood Disorder In Pregnancy. ScienceDaily. Retrieved October 23, 2014 from www.sciencedaily.com/releases/2008/04/080403202738.htm
BMJ-British Medical Journal. "New Test Could Cut Unnecessary Treatment For Blood Disorder In Pregnancy." ScienceDaily. www.sciencedaily.com/releases/2008/04/080403202738.htm (accessed October 23, 2014).

Share This



More Health & Medicine News

Thursday, October 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Ebola Fears Keep Guinea Hospitals Empty

Ebola Fears Keep Guinea Hospitals Empty

AP (Oct. 23, 2014) Fears of Ebola are keeping doctors and patients alike away from hospitals in the West African nation of Guinea. (Oct. 23) Video provided by AP
Powered by NewsLook.com
Orthodontist Mom Jennifer Salzer on the Best Time for Braces

Orthodontist Mom Jennifer Salzer on the Best Time for Braces

Working Mother (Oct. 22, 2014) Is your child ready? Video provided by Working Mother
Powered by NewsLook.com
U.S. Issues Ebola Travel Restrictions, Are Visa Bans Next?

U.S. Issues Ebola Travel Restrictions, Are Visa Bans Next?

Newsy (Oct. 22, 2014) Now that the U.S. is restricting travel from West Africa, some are dropping questions about a travel ban and instead asking about visa bans. Video provided by Newsy
Powered by NewsLook.com
More People Diagnosed With TB In 2013, But There's Good News

More People Diagnosed With TB In 2013, But There's Good News

Newsy (Oct. 22, 2014) The World Health Organizations says TB numbers rose in 2013, but it's partly due to better detection and more survivors. Video provided by Newsy
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:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

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