11 July 2011
ByAppeared in BioNews 615
Some of the highlights from the 27th Annual Meeting of the European Society of Human Reproduction (ESHRE) in Stockholm include good news for sperm donation in the UK; advice about how to reduce the effects of tobacco on unborn children; a 'non invasive' screening technique for chromosomal abnormalities in embryos; and a mathematical model to help reduce multiple births in IVF procedures.
UK sperm crisis 'averted'
On Monday, the London Sperm Bank (LSB) presented encouraging results from its recent marketing campaign to recruit the 500 sperm donors necessary to meet the current need in the UK.
It reports that between March and December 2010 potential donor enquiries numbered 3,062, and of the 397 men who attended an interview 34 percent went on to join the program. The research team says that the 2,410 donations now stored could theoretically provide over 2,000 treatment cycles, which is around half of the annual UK demand.
Dr Gulam Bahadur from the LSB believes its approach of promoting dedicated facilities with sympathetic surroundings; a humorous logo aimed at a wider audience; an advanced quality management system focused on listening, engaging and reacting to potential donors' needs; and an improved follow-up system will encourage the behavioural change needed to recruit more donors.
Quit smoking when you find out you're pregnant and your baby won't suffer
Stopping smoking when you find out you are pregnant is enough to avoid the adverse effects of tobacco on your baby, UK researchers reported on Wednesday.
Dr Nick Macklon and his team at the University of Southampton used data from more than 50,000 pregnancies to show that women who gave up smoking when they realised they were pregnant had babies with similar birth weights to women who had never smoked.
The results were adjusted for factors that are linked to birth outcomes, such as obesity, maternal age and socio-economic background. However, Dr Macklon did warn that smoking can adversely affect fertility, making it harder for couples to conceive. He said the message is that if you do fall pregnant while you are still smoking 'it's not too late to do something about it'.
'Non-invasive' chromosome test revealed
A new way of checking that embryos implanted during assisted reproductive therapies have the correct number of chromosomes was revealed on Wednesday.
The current methods of PGS involve taking a cell directly from the embryo to test it for conditions such as Down's syndrome, or biopsying a part of the woman's egg before it is fertilised. Both procedures risk the egg and embryo's survival.
'If chromosomal abnormalities in the egg result in changes in the surrounding cumulous cells, it is possible that this could lead to a new way of testing eggs, before they are fertilised', said Dr Fragouli. 'Cumulous cells are routinely stripped off eggs during IVF treatments and are usually discarded, so it should be straightforward to obtain them for analysis'.
The research team are currently comparing the standard methods of PGS with their new approach and, with good results, will undertake a clinical trial next year.
Mathematical model developed to reduce twins while maintaining good pregnancy chances
Swedish researchers have developed a mathematical model that can predict whether women should undergo single or double embryo transfer, thereby maximising the chances of pregnancy while reducing the risk of a multiple birth.
Dr Jan Holte from Carl von Linneklinikken in Uppsala, Sweden found that combining four factors – the quality of the embryo, the age of the woman, her ovarian responsiveness, and information about any previous IVF attempts, such as whether they involved fresh or frozen cycles – reduced the twin rate while maintaining live birth rates.
This model was used in his clinic between 2004 and 2007 for 3,410 embryo transfers, and compared to 1999-2002 the amount of single embryo transfers increased from 11.1 percent to 76.2 percent. The rate of twin deliveries dropped from 26.1 percent to just 1.9 percent, while live births remained at similar levels.'The results suggest that application of the model may reduce twin rates to the desired level, in our case that of the normal Swedish population, while totally preserving pregnancy rates and markedly reducing risks for the offspring', he commented.