Fertility Blog

ASRM 2005 Roundup

![](http://www.pacificfertilitycenter.com/fertilityflash/vol3-10/ASRM05Banner.jpg)#### Nicotine Damage to Sperm Better Understood An experiment led by researchers from the State University at Buffalo School of Medicine revealed that chronic male smokers could experience a reduction in their fertility of up to 75% as compared to non-smokers. Lani Burkman led the study to provide more details on past research, which had shown that when nicotine and its by-product, cotinine, were added to sperm in the lab, these chemicals changed the way the sperm moved. In this recent research, sperm from both smokers and non-smokers were combined in two different Petri dishes with oocytes derived from one source. The sperm’s ability to bind to and penetrate the zona pellucida (outer shell) was carefully observed. In summary, the smokers' sperm were less effective in binding to the zona pellucida. The sperm of chronic smokers - people who have smoked a minimum of four cigarettes a day for at least two years – maintained an average of 75% less capacity to fertilize compared to nonsmokers. The researchers also discovered that light smokers’ sperm performed better than chronic smokers’, suggesting that men trying to start a family will have better results even by cutting back on the smoking. #### Knowledge of Egg Freezing Advancing Rapidly Fourteen papers on the topic of oocyte cryopreservation were presented. Some focused on studying overall results since egg freezing was first introduced in the late 1980s, while other presentations reported on testing specific methodologies, such as slow vs rapid freeze and thaw techniques, or the use of different cryoprotectants. Results continue to bode well but specifically for women who are relatively young. In what the media hailed as a breakthrough, one research team presented what could be the highest success rate for oocyte cryopreservation to date. Led by John Jain, MD, an associate professor of Reproductive Endocrinology at University of Southern California, the team’s egg-freezing protocol involves the use of slow freezing and fast thawing, in addition to a specific culture medium that applies choline for stabilizing the egg’s membrane. The research was derived from a small study involving only eight infertile women with tubal factors, all around the age of 31. Out of the eight women trying to conceive, five achieved pregnancies with their own previously frozen oocytes. For the particular study group, this translates into a 62% success rate per patient, which is comparable to fresh embryo transfers. However, Dr. Jain stressed that considerably more research needs to take place before egg freezing should be used in standard clinical practice. More good news for oocyte cryopreservation came out of a research team from McGill University in Montreal, Canada. This team applied a proprietary blended cryoprotectant formula and used only the vitrification (rapid freeze) method in contrast to the more standard slow freeze protocol. In this case, 180 oocytes that were derived from 15 women of mean age 31.7 were vitrified. Out of these, 169 survived the fast freeze process (93.9%), and 126 oocytes fertilized normally (74.6%). Out of the original 15 patients, 4 are currently showing signs of successful pregnancies and one has already delivered. #### More Worries About Multiples Ongoing research continues to identify problems with multiple gestation births, some involving assisted reproduction, some not. ***Genetic Testing Important for Twins:*** Researchers at UCLA’s School of Medicine working with the Cedars-Sinai Medical Center identified higher rates of cytogenetic abnormalities in the first trimester of twin gestations conceived through IVF compared to spontaneously conceived twins. The team set out to discover whether the previously suggested increased incidence of aneuploidy in twins might be related to IVF. This retrospective case-controlled study analyzed women at least 35 years of age carrying dizygotic twins who underwent chorionic villus sampling (CVS) at these institutions between 2000 – 2004. The average age of the patients carrying twins from IVF was slightly higher (2 years) than those with twins who conceived naturally. Out of the 27 women carrying twins conceived through IVF, the incidence of aneuploidy was 14.8%. Out of the 14 women carrying twins conceived spontaneously the aneuploidy incidence was 0%. Because genetic abnormalities can be identified through CVS early in the pregnancy, the paper points to the importance of counseling. (Note: Those who require IVF may already have an increased incidence of genetic abnormalities unrelated to the IVF process. Continued study is needed.) ***Vanishing Twins Provide Clues:*** A research team at UCSF studied the gestational sacs of 244 births resulting from IVF/ICSI and found that singletons born with a so-called vanishing twin were more likely to have adverse perinatal outcomes including low birth weight, premature birth and stillbirth incidences, suggesting abnormalities start in early placentation. They are now calling for a larger sample size to confirm the data. Female Twins Reach Early Menopause: Weill Medical College of Cornell University researchers presented data suggesting that female twins are more likely to undergo premature menopause. Although identical twins showed a higher incidence than non-identical twins, both groups showed significantly higher rates than their non-twin counterparts from the general population. Statistically speaking, only about 1% of women reach menopause by age 40. The twins from this study revealed that about 5% reached premature ovarian failure and showed menopausal symptoms by age 40. In some cases, only one twin out of a pair entered early menopause. This joint study involved a survey of 850 women from different twin populations around the world collected by the Queensland Institute of Medical Research in Brisbane, Australia; St. Thomas's Hospital in London and St. Luke's Hospital in St. Louis, Missouri. ***Infertile Women Want Twins:*** While the news about multiple gestations continues to raise concerns, a group out of the University of Iowa, Carver College of Medicine confirmed earlier research indicating that infertile women desire twins at twice the rate of their fertile counterparts. This research team used a questionnaire-based prospective study to survey over 1000 maternity patients and found that 20% of infertile women conveyed a preference for twins compared to 10% of fertile women. #### Pollution Has Impact in Brazil Two research groups from the School of Medicine at the University of São Paulo in São Paulo, Brazil are studying the impacts of air pollution on reproductive health. One study group focused on early miscarriage by exposing mice to ambient air pollution from rush hour traffic, compared to a control group placed in a less polluted environment. The exposed mice group had 80% of the early gestational miscarriages recorded out of the combined set. Specific pollution types and quantities were not listed in this study. The other study analyzed the possible impact of increased ambient air pollution on gender outcome of live births of both humans and mice. In this study the researchers correlated live birth data to 15 air pollution monitoring stations in the city of São Paulo. They analyzed birth registries between January 2001 and December 2003, and correlated conception dates to the pollution levels of each station. In the least polluted area the sex ratio was 51.7% males for 34,795 births recorded, and for the most polluted area the proportion decreased to 50.7% for 48,023 births recorded, indicating a difference of 1% in total male births. Similar findings were observed in the experimental study involving mice placed in polluted vs filtered chambers. In the filtered chamber the male/female ratio was 1.34 opposed to 0.86 in the non-filtered chamber. ![](http://www.pacificfertilitycenter.com/fertilityflash/vol3-9/LabCoats.jpg) Left to right: Front row: Carl Herbert, MD, Isabelle Ryan, MD Back row: Joe Conaghan, PhD, Eldon Schriock, MD, Carolyn Givens, MD, Philip Chenette, MD The physicians at Pacific Fertility Center are internationally recognized specialists in reproductive endocrinology and infertility. They have completed top-level medical education, published groundbreaking professional papers, and held positions on the faculty of leading research universities. They continue to participate in reproductive research. All MDs are Board Certified by ABOG as Reproductive Endocrinology and Infertility Specialists. Our state-of-the-art laboratory has one of the most highly trained teams in the country.
Posted on December 8th, 2005

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