Featured Research

from universities, journals, and other organizations

First Trimester Smoking Linked To Oral Clefts

Date:
December 23, 2008
Source:
Norwegian Institute of Public Health
Summary:
Smoking during the first trimester of pregnancy is clearly linked with an increased risk of cleft lip in newborns. Genes that play a role in detoxification of cigarette smoke do not appear to be involved, according to a new study.

Smoking during the first trimester of pregnancy is clearly linked with an increased risk of cleft lip in newborns. Genes that play a role in detoxification of cigarette smoke do not appear to be involved. This is shown in a new study published in the journal Epidemiology.

Oral clefts are one of the most common birth defects. Closure of the lip occurs about 5 weeks into pregnancy, followed by closure of the palate at week 9. If this does not happen, a cleft lip and/or cleft palate are the result, requiring surgery. The researchers wanted to see if smoking or exposure to passive smoking play a role in these defects and whether genes influence the oral cleft riskthrough the way toxic chemicals in cigarette smoke are processed.

The study is based on an extensive Norwegian case-control study on oral clefts with collaborating researchers from the Norwegian Institute of Public Health, University of Bergen, Rikshospital, HaukelandUniversity Hospitaland the National Institutes of Health in USA. Between 1996 and 2001, 676 babies born with oral clefts were referred for cleft surgery, and of these, 573 took part in the study. 763 babies born during the same period in Norway were randomly selected as controls.

DNA and questionnaires

Blood samples were taken from the children referred for surgery and their PKU test samples,routinely takenat birth, were also retrieved. Their mothers and fathers donated cheek swabs and blood samples. From the control group, cheek swabs were obtained from the mother, father (after November 1998) and child, plus the PKU test sample taken at birth. DNA was extracted from the samples.

Four weeks after birth, the mothers in both groups completed a questionnaire about medical conditions and environmental exposure. They were specifically asked about their smoking habits and exposure to passive smoking before pregnancy and during the first trimester. 42 % of case mothers and 32 % of control mothers said that they smoked in the first trimester.

There was little evidence of an effect of smoking on the risk of cleft palate alone. However, for cleft lip (with or without cleft palate), there was an increased risk, almost two-fold when the mother smoked over 10 cigarettes per day and a 1.6 fold risk from passive smoking (defined as being within 2 metres of a smoker for 2 hours a day). The researchers estimate that 19 % of cases of cleft lip in Norway may be due to maternal smoking in the first trimester.

Genetic Analysis

Using the DNA extracted from the babies and their parents, the researchers looked at the genes related to detoxification of chemicals in cigarette smoke (NAT1, NAT2, CYP1A1, GSTP1, GSTT1, GSTM1). These genes did not appear to affect the incidence of cleft lip, although there was an inconclusive link with NAT2 and cleft lip risk which was independent of smoking. The mechanism by which maternal smoking increases the risk of cleft lip remains unknown.


Story Source:

The above story is based on materials provided by Norwegian Institute of Public Health. Note: Materials may be edited for content and length.


Journal Reference:

  1. RT Lie, AJ Wilcox, J Taylor, HK Gjessing, OD Saugstad, F Aabyholm and H Vindenes. Maternal Smoking and Oral Clefts. Epidemiology, 2008; 19 (4): 606-615

Cite This Page:

Norwegian Institute of Public Health. "First Trimester Smoking Linked To Oral Clefts." ScienceDaily. ScienceDaily, 23 December 2008. <www.sciencedaily.com/releases/2008/12/081218094559.htm>.
Norwegian Institute of Public Health. (2008, December 23). First Trimester Smoking Linked To Oral Clefts. ScienceDaily. Retrieved April 18, 2014 from www.sciencedaily.com/releases/2008/12/081218094559.htm
Norwegian Institute of Public Health. "First Trimester Smoking Linked To Oral Clefts." ScienceDaily. www.sciencedaily.com/releases/2008/12/081218094559.htm (accessed April 18, 2014).

Share This



More Health & Medicine News

Friday, April 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

'Holy Grail' Of Weight Loss? New Find Could Be It

'Holy Grail' Of Weight Loss? New Find Could Be It

Newsy (Apr. 18, 2014) In a potential breakthrough for future obesity treatments, scientists have used MRI scans to pinpoint brown fat in a living adult for the first time. Video provided by Newsy
Powered by NewsLook.com
Little Progress Made In Fighting Food Poisoning, CDC Says

Little Progress Made In Fighting Food Poisoning, CDC Says

Newsy (Apr. 18, 2014) A new report shows rates of two foodborne infections increased in the U.S. in recent years, while salmonella actually dropped 9 percent. Video provided by Newsy
Powered by NewsLook.com
Scientists Create Stem Cells From Adult Skin Cells

Scientists Create Stem Cells From Adult Skin Cells

Newsy (Apr. 17, 2014) The breakthrough could mean a cure for some serious diseases and even the possibility of human cloning, but it's all still a way off. Video provided by Newsy
Powered by NewsLook.com
Obama: 8 Million Healthcare Signups

Obama: 8 Million Healthcare Signups

AP (Apr. 17, 2014) President Barack Obama gave a briefing Thursday announcing 8 million people have signed up under the Affordable Care Act. He blasted continued Republican efforts to repeal the law. (April 17) 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