Human sperm hardiest in winter
Source: Agencies |
March 12, 2013, Tuesday
|
Print Edition
Print Edition
AUTUMN is the time of year most associated with bumper crops of new babies, and according to an Israeli study there may be a scientific reason: Human sperm are generally at their healthiest in winter and early spring.
Based on samples from more than 6,000 men treated for infertility, researchers writing in American Journal of Obstetrics & Gynecology found sperm in greater numbers, with faster swimming speeds and fewer abnormalities in semen made during winter, with a steady decline in quality as of spring.
"The winter and spring semen patterns are compatible with increased fecundability and may be a plausible explanation of the peak number of deliveries during the fall," wrote lead researcher Eliahu Levitas from Ben-Gurion University of the Negev in Beer-Sheva.
If there is a seasonal pattern, they said, that knowledge may "be of paramount importance, especially in couples with male-related infertility struggling with unsuccessful and prolonged fertility treatments."
Taking into account the approximately 70 days it takes for the body to produce a sperm cell, the researchers found that men with normal sperm production had the healthiest sperm in the winter.
For example, those men produced about 70 million sperm per milliliter of semen during the winter. About 5 percent of those sperm had "fast" motility, or swimming speed, which improves a couple's chance of getting pregnant.
That compared to the approximately 68 million sperm per milliliter the men produced in the spring, of which only about 3 percent were "fast."
For men with abnormal sperm production, however, the pattern didn't hold. Those men showed a slight trend toward better motility during the fall and made the largest percentage of normal shaped sperm - about 7 percent - during the spring.
"Based on our results the (normal) semen will perform better in winter, whereas infertility cases related to low sperm counts should be encouraged to choose spring and fall," the researchers wrote.
Animal studies have found results in line with those species' breeding seasons.
Based on samples from more than 6,000 men treated for infertility, researchers writing in American Journal of Obstetrics & Gynecology found sperm in greater numbers, with faster swimming speeds and fewer abnormalities in semen made during winter, with a steady decline in quality as of spring.
"The winter and spring semen patterns are compatible with increased fecundability and may be a plausible explanation of the peak number of deliveries during the fall," wrote lead researcher Eliahu Levitas from Ben-Gurion University of the Negev in Beer-Sheva.
If there is a seasonal pattern, they said, that knowledge may "be of paramount importance, especially in couples with male-related infertility struggling with unsuccessful and prolonged fertility treatments."
Taking into account the approximately 70 days it takes for the body to produce a sperm cell, the researchers found that men with normal sperm production had the healthiest sperm in the winter.
For example, those men produced about 70 million sperm per milliliter of semen during the winter. About 5 percent of those sperm had "fast" motility, or swimming speed, which improves a couple's chance of getting pregnant.
That compared to the approximately 68 million sperm per milliliter the men produced in the spring, of which only about 3 percent were "fast."
For men with abnormal sperm production, however, the pattern didn't hold. Those men showed a slight trend toward better motility during the fall and made the largest percentage of normal shaped sperm - about 7 percent - during the spring.
"Based on our results the (normal) semen will perform better in winter, whereas infertility cases related to low sperm counts should be encouraged to choose spring and fall," the researchers wrote.
Animal studies have found results in line with those species' breeding seasons.
- About Us
- |
- Terms of Use
- |
-
RSS - |
- Privacy Policy
- |
- Contact Us
- |
- Shanghai Call Center: 962288
- |
- Tip-off hotline: 52920043
- 沪ICP证：沪ICP备05050403号-1
- |
- 互联网新闻信息服务许可证：31120180004
- |
- 网络视听许可证：0909346
- |
- 广播电视节目制作许可证：沪字第354号
- |
- 增值电信业务经营许可证：沪B2-20120012
Copyright © 1999- Shanghai Daily. All rights reserved.Preferably viewed with Internet Explorer 8 or newer browsers.
