Featured Research

from universities, journals, and other organizations

Success of IVF varies with season of the year, study suggests

Date:
September 14, 2010
Source:
International Federation of Fertility Societies
Summary:
The success of an assisted reproduction procedure may depend on the season, a new study suggests.

The success of an assisted reproduction procedure may depend on the season. This is the finding of new work presented at the World Congress of Fertility and Sterility, in Munich, Germany.

Related Articles


Scientists have long noted that there are seasonal variations in the number of natural human births. No firm explanation has been put forward for this, but speculation is that human reproduction is linked to temperature and season. Now new research indicates that even Assisted Reproduction may be more effective at certain times of year.

A team led by Dr Daniela Braga (Sao Paolo, Brazil) looked at the cytological and biochemical parameters of 1932 patients undergoing egg retrieval for intracytoplasmic sperm injection (ICSI)*, during different seasons of the year. All patients came from a single fertility center, the Assisted Fertilization Center in Sao Paulo -- Brazil.

They looked at 435 patients in winter (representing 22.5% of the total sample), 444 in spring (23.0%), 469 in summer (24.2%), and 584 in autumn (30.3%).

They found that the percentage of developing eggs (MII oocytes), high-quality embryos, implantation, and pregnancy rates did not differ among the groups. Nevertheless the fertilization rate was significantly higher during the spring than during any other season (winter: 67.9; spring: 73.5%, summer: 68.7% and autumn: 69.0%). In fact they report a

1.45-fold increase in the fertilization rate during the spring**.

The team also measured the levels of different hormones, and found that 17-β estradiol*** levels were significantly higher in the spring.

Dr Braga said: "This work shows that IVF cycles may have a better outcome during the Spring. Our results show a significant difference in spring fertilization rate, with the fertilization rate in the spring being almost one and a half-times that of other seasons. In practical terms this may mean that if you are having real difficulty in conceiving, it may be better to have an assisted reproduction cycle during this season.

It is possible that what we are seeing is the effect of changing light on neurons in the brain which produce gonadotrophin-releasing hormones (GnRH). These neurons regulate the secretion of gonadotrophin hormones****, which in turn control the secretion of estradiol from the ovaries. We found higher 17-β estradiol levels in the spring; in assisted reproduction, adequate estradiol levels are important for egg maturation and other reproductive processes including fertilization and embryo development.

Our next step is to check if there is any difference in the ICSI outcomes in different regions in Brazil. Brazil of course is a very large country, and we have different day lengths in different regions, so we may see differences from region to region depending on the latitude ."

Notes:

*IntraCytoplasmic Sperm Injection (ICSI) is a procedure in which sperm is injected into the oocyte (egg) cytoplasm.

**The team used logistic regression analysis to test the influence of the season (spring) in the results. These analyses produced an Odds Ration of 1.45. For comparison, an Odds Ratio of 1 means there is no effect of the variable being analyzed, whereas in this case the OR of 1.45 means there is an almost one and a half times increase in chance of fertilization.

***17-β estradiol is the main estrogen found in women between the ages of puberty and menopause.

**** Gonadotrophins are protein hormones secreted by the pituitary gland (at the base of the brain).


Story Source:

The above story is based on materials provided by International Federation of Fertility Societies. Note: Materials may be edited for content and length.


Cite This Page:

International Federation of Fertility Societies. "Success of IVF varies with season of the year, study suggests." ScienceDaily. ScienceDaily, 14 September 2010. <www.sciencedaily.com/releases/2010/09/100913182445.htm>.
International Federation of Fertility Societies. (2010, September 14). Success of IVF varies with season of the year, study suggests. ScienceDaily. Retrieved October 24, 2014 from www.sciencedaily.com/releases/2010/09/100913182445.htm
International Federation of Fertility Societies. "Success of IVF varies with season of the year, study suggests." ScienceDaily. www.sciencedaily.com/releases/2010/09/100913182445.htm (accessed October 24, 2014).

Share This



More Health & Medicine News

Friday, October 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

IKEA Desk Converts From Standing to Sitting With One Button

IKEA Desk Converts From Standing to Sitting With One Button

Buzz60 (Oct. 24, 2014) IKEA is out with a new convertible desk that can convert from a sitting desk to a standing one with just the push of a button. Jen Markham explains. Video provided by Buzz60
Powered by NewsLook.com
Ebola Protective Suits Being Made in China

Ebola Protective Suits Being Made in China

AFP (Oct. 24, 2014) A factory in China is busy making Ebola protective suits for healthcare workers and others fighting the spread of the virus. Duration: 00:38 Video provided by AFP
Powered by NewsLook.com
WHO: Millions of Ebola Vaccine Doses by 2015

WHO: Millions of Ebola Vaccine Doses by 2015

AP (Oct. 24, 2014) The World Health Organization said on Friday that millions of doses of two experimental Ebola vaccines could be ready for use in 2015 and five more experimental vaccines would start being tested in March. (Oct. 24) Video provided by AP
Powered by NewsLook.com
Doctor in NYC Quarantined With Ebola

Doctor in NYC Quarantined With Ebola

AP (Oct. 24, 2014) An emergency room doctor who recently returned to the city after treating Ebola patients in West Africa has tested positive for the virus. He's quarantined in a hospital. (Oct. 24) 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