Featured Research

from universities, journals, and other organizations

Men Who Smoke Heavily May Impair Sperm, Fertility

Date:
October 18, 2005
Source:
University at Buffalo
Summary:
Men who smoke cigarettes may experience a significant decline in their capacity to father a child, research by a reproductive medicine specialist from the University at Buffalo has shown.

Spermfrom nearly two-thirds of the chronic smokers in the study failed aspecial test that measures the ability of sperm to fertilize an egg. Onaverage, those men showed a 75 percent decline in fertilizing capacitywhen compared to nonsmokers.

Lead researcher Loni Burkman, Ph.D.,presented the results today (Oct. 17, 2005) at the American Society ofReproductive Medicine annual meeting in Montreal, Quebec.

Burkmanis associate professor and head of the Section on Andrology, Departmentof Gynecology and Obstetrics in the UB School of Medicine andBiomedical Sciences and an assistant professor of urology.

"Likeother cells in the body, human sperm carry a receptor for nicotine,which means they recognize and respond to nicotine," said Burkman."This happens because nicotine from tobacco mimics one of the mostimportant neurochemicals produced in the body.

"Using sperm ofnonsmokers, we reported previously that the addition of nicotinechanged three sperm functions required to fertilize an egg.

"Inthis new study, we examined whether sperm from chronic tobacco smokersare defective in binding to the zona, the cover surrounding an egg,"said Burkman. "Our results could mean that heavy smoking overloads thenicotine receptor in human sperm and in the testes, leading to adecline in fertilizing potential."

The study involved 18 men whoreported smoking at least four cigarettes a day, every day, for morethan two years. On average, these men had smoked for about 15 years.Their sperm function was compared to that of non-smoking donors whoserved as controls and whose fertilizing capacity had been confirmed.

Usinga test called the Hemizona Assay developed by Burkman, the researcherscut a zona in half, placing one half with a smoker's sperm and thematching half with control sperm. After two to three hours ofincubation, researchers counted the number of sperm attached tightly tothe outside of each half.

The number of attached sperm from thesmoker was compared to the control number, which gave a ratio or index.The Hemizona Assay has been shown to predict fertilization failureduring in vitro fertilization.

"To fail, the index must be lessthan 65, meaning that the smoker's sperm had less than 65 percent ofthe fertilizing capacity found in the donor," Burkman said. "An indexbelow 36 identifies a severe loss in fertilizing capacity."

Resultsshowed that the sperm from almost two-thirds of the smokers failed thetest, while the remainder showed normal function. Almost all thesmokers whose sperm failed the test had an index of 36 or less, with anaverage of 25.

"None of these men had a zero fertilizingpotential," said Burkman, "but the results mean that their sperm hadonly 25 percent of the fertilizing function found in nonsmoking men.The data also showed that the men who failed were smoking about twiceas many cigarettes per day, an average of 19 per day, compared to thesmokers who passed the assay."

As another way to understand theimpact of smoking, the researchers calculated a "smoking load" for eachsmoker by multiplying the number of cigarettes smoked per day by thenumber of years smoked. The load varied from 16 to 750 for the 18 men.

Resultsshowed that the men who smoked fewer cigarettes for fewer years hadsmaller smoking loads, ranging from 16 to 200. In this group, 71percent passed the Hemizona Assay, indicating normal fertility. Theremaining men had a high smoking load, and only 18 percent passed theassay.

"Specialized testing clearly reveals a significant drop infertility potential for men who are heavy tobacco smokers," saidBurkman. "Smoking men also should be aware that smoking can damagetheir sperm DNA, passing on faulty DNA to their baby. Concerned smokersshould quit or be tested in a local andrology laboratory."

Burkman added that other scientists have shown a similar decline in fertility among women who are heavy smokers.

RoxanneMroz and MaryLou Bodziak, UB research associates, contributed to thiswork, along with UB undergraduate students Stuti Tambar, Brian Telesz,and Scott Beardsley.

The research was funded by the Philip Morris External Research Program.

TheUniversity at Buffalo is a premier research-intensive publicuniversity, the largest and most comprehensive campus in the StateUniversity of New York.


Story Source:

The above story is based on materials provided by University at Buffalo. Note: Materials may be edited for content and length.


Cite This Page:

University at Buffalo. "Men Who Smoke Heavily May Impair Sperm, Fertility." ScienceDaily. ScienceDaily, 18 October 2005. <www.sciencedaily.com/releases/2005/10/051018080741.htm>.
University at Buffalo. (2005, October 18). Men Who Smoke Heavily May Impair Sperm, Fertility. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/2005/10/051018080741.htm
University at Buffalo. "Men Who Smoke Heavily May Impair Sperm, Fertility." ScienceDaily. www.sciencedaily.com/releases/2005/10/051018080741.htm (accessed July 31, 2014).

Share This




More Health & Medicine News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Health Insurers' Profits Slide

Health Insurers' Profits Slide

Reuters - Business Video Online (July 30, 2014) Obamacare-related costs were said to be behind the profit plunge at Wellpoint and Humana, but Wellpoint sees the new exchanges boosting its earnings for the full year. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
Concern Grows Over Worsening Ebola Crisis

Concern Grows Over Worsening Ebola Crisis

AFP (July 30, 2014) Pan-African airline ASKY has suspended all flights to and from the capitals of Liberia and Sierra Leone amid the worsening Ebola health crisis, which has so far caused 672 deaths in Guinea, Liberia and Sierra Leone. Duration: 00:43 Video provided by AFP
Powered by NewsLook.com
At Least 20 Chikungunya Cases in New Jersey

At Least 20 Chikungunya Cases in New Jersey

AP (July 30, 2014) At least 20 New Jersey residents have tested positive for chikungunya, a mosquito-borne virus that has spread through the Caribbean. (July 30) Video provided by AP
Powered by NewsLook.com
Xtreme Eating: Your Daily Caloric Intake All On One Plate

Xtreme Eating: Your Daily Caloric Intake All On One Plate

Newsy (July 30, 2014) The Center for Science in the Public Interest released its 2014 list of single meals with whopping calorie counts. 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:
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