Featured Research

from universities, journals, and other organizations

Taking Contraceptive Pill May Reduce Risk Of Developing Cancer, Study Suggests

Date:
September 12, 2007
Source:
British Medical Journal
Summary:
Taking the contraceptive pill does not increase a woman's chances of developing cancer and may even reduce the risk for most women, according to a new study. However, there was an increased risk for women who used it for more than eight years.

Since its introduction in the early 1960s, more than 300 million women are thought to have used oral contraception.
Credit: iStockphoto/Marie-france Bιlanger

Taking the contraceptive pill does not increase a woman's chances of developing cancer and may even reduce the risk for most women, according to a study published by the British Medical Journal.

Related Articles


However, there was an increased risk for women who used it for more than 8 years.

Since its introduction in the early 1960s, more than 300 million women are thought to have used oral contraception. Although several studies have looked at the overall balance of cancer deaths associated with oral contraceptives, none have so far examined the absolute risks or benefits.

Researchers from the University of Aberdeen analysed data spanning a 36 year period from the Royal College of General Practitioners (RCGP) Oral Contraception Study which began in 1968. The study recruited 46,000 women, with an average age of 29. Approximately half were using oral contraceptives; the other half had never taken it.

Every six months their GP provided the study with information on the women's health. In addition, three quarters of the women were 'flagged' at the NHS central registries so that deaths and cancers were notified to the study even if women had left their recruitment GP.

Professor Philip Hannaford and colleagues used the data to calculate the risk of developing any type of cancer and the main gynaecological cancers combined. They also considered the effects of variables such as age, smoking and social class.

Given the length of the study a significant number of GPs had not been able to provide updates throughout the entire study period, for example if a woman moved out of the area of their doctor. So Professor Hannaford and colleagues from the University of Aberdeen's Department of General Practice and Primary Care calculated the cancer risks using two sets of data. One that related to cancers reported while the women remained registered with their recruiting GP and whose information was more detailed (GP observation dataset) The second main study dataset which was larger, also included cancers notified by the central NHS registries after women had left their recruiting GP.

In both data sets there was no overall increased risk of cancer among pill users. When the GP observation dataset was used, women who had taken the pill at some time during their lives had a 3% reduced risk of developing any cancer. When the larger main dataset was used, the reduction was 12%. A 12% reduction equates to approximately one fewer case of cancer for every 2,200 women who have used the pill for a year and 3% equates to one fewer case of cancer for every 10,000 women.

In the main dataset women on the pill had statistically significant lower rates of large bowel/rectal, uterine body and ovarian cancer. The GP dataset also showed a reduced risk of uterine and ovarian cancer.

The researchers did sound a note of caution. When the women were examined by how long they had used the pill, women who used it for more than 8 years -- less than a quarter of pill users in the study - had a statistically significant increased risk of developing any cancer, in particular cervical and central nervous system cancer. However the same women were at reduced risk of developing ovarian cancer. Evidence suggests that the protective effect of taking the pill lasts for at least 15 years after stopping.

The authors say that many women, especially those who used the first generation of oral contraceptives many years ago, are likely to find the results reassuring:

"In this UK cohort oral contraception was not associated with an overall increased risk of any cancer, indeed it may even produce a net public health gain.


Story Source:

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


Cite This Page:

British Medical Journal. "Taking Contraceptive Pill May Reduce Risk Of Developing Cancer, Study Suggests." ScienceDaily. ScienceDaily, 12 September 2007. <www.sciencedaily.com/releases/2007/09/070911202503.htm>.
British Medical Journal. (2007, September 12). Taking Contraceptive Pill May Reduce Risk Of Developing Cancer, Study Suggests. ScienceDaily. Retrieved January 29, 2015 from www.sciencedaily.com/releases/2007/09/070911202503.htm
British Medical Journal. "Taking Contraceptive Pill May Reduce Risk Of Developing Cancer, Study Suggests." ScienceDaily. www.sciencedaily.com/releases/2007/09/070911202503.htm (accessed January 29, 2015).

Share This


More From ScienceDaily



More Health & Medicine News

Thursday, January 29, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Malnutrition on the Rise as Violence Flares in C. Africa

Malnutrition on the Rise as Violence Flares in C. Africa

AFP (Jan. 28, 2015) — Violence can flare up at any moment in Bambari with only a bridge separating Muslims and Christians. Malnutrition is on the rise and lack of water means simple cooking fires threaten to destroy makeshift camps where people are living. Duration: 00:40 Video provided by AFP
Powered by NewsLook.com
Poultry Culled in Taiwan to Thwart Bird Flu

Poultry Culled in Taiwan to Thwart Bird Flu

Reuters - News Video Online (Jan. 28, 2015) — Taiwan culls over a million poultry in efforts to halt various strains of avian flu. Julie Noce reports. Video provided by Reuters
Powered by NewsLook.com
Media Criticizing Parents For Not Vaccinating Children

Media Criticizing Parents For Not Vaccinating Children

Newsy (Jan. 28, 2015) — As the Disneyland measles outbreak continues to spread, the media says parents who choose not to vaccinate their children are part of the cause. Video provided by Newsy
Powered by NewsLook.com
Shark Bite Victim Making Amazing Recovery

Shark Bite Victim Making Amazing Recovery

AP (Jan. 27, 2015) — A Texas woman who lost more than five pounds of flesh to a shark in the Bahamas earlier this month could be released from a Florida hospital soon. Experts believe she was bitten by a bull shark while snorkeling. (Jan. 27) 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:

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