Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Drinking alcohol during pregnancy may damage semen quality in sons

29.06.2010
Mothers who drink alcohol while they are pregnant may be damaging the fertility of their future sons, according to new research to be presented at the 26th annual meeting of the European Society of Human Reproduction and Embryology in Rome today (Tuesday 29 June).

Doctors in Denmark found that if mothers had drunk 4.5 or more drinks a week while pregnant, then the sperm concentration of their sons, measured about 20 years later, was a third lower in comparison to men who were not exposed to alcohol while in the womb. A drink was measured as 12 grams of alcohol, which is the equivalent to one 330 ml beer, one small (120 ml) glass of wine or one glass of spirits (40 ml).

Dr Cecilia Ramlau-Hansen, senior researcher at the Department of Occupational Medicine, Aarhus University Hospital (Denmark) and clinical associate professor at the Department of Epidemiology, Institute of Public Health, University of Aarhus, told a news briefing: "Our study shows that there is an association between drinking a moderate amount of alcohol (about four to five drinks a week) during pregnancy and lower sperm concentrations in sons. However, because this is an observational study we cannot say for certain that the alcohol causes the lower sperm concentrations. It is possible that drinking alcohol during pregnancy has a harmful effect on the foetal semen-producing tissue in the testes – and thereby on semen quality in later life – but our study is the first of its kind, and more research within this area is needed before any causal link can be established or safe drinking limits proposed."

Dr Ramlau-Hansen and her colleagues studied 347 sons of 11,980 women with singleton pregnancies who were recruited to the Danish "Healthy habits for two" study between 1984-1987. Around the 36th week of pregnancy the mothers answered a questionnaire on lifestyles and health. The sons were followed up between 2005-2006, when they were aged between 18-21, and semen and blood samples were collected and analysed.

The researchers divided the sons into four groups, ranging from those who were least exposed to alcohol (their mothers had drunk less than one drink a week) – and this was the reference group against which the other groups were measured – to those whose mothers drank 1-1.5 drinks a week, 2-4 drinks a week, or 4.5 or more drinks per week.

They found that sons of mothers drinking 4.5 or more alcoholic drinks a week had average sperm concentrations of 25 million per millilitre, while the sons who were least exposed to alcohol had sperm concentrations of 40 million/ml. After adjusting for various confounding factors, they found the sons in the group most exposed to alcohol had an average sperm concentration that was approximately 32% lower than that in the least exposed group.

The World Health Organization defines a "normal" level of sperm concentration as being approximately 20 million/ml or more. Dr Ramlau-Hansen said: "The reduced sperm concentrations in the most exposed men are rather close to the lower end of the WHO's normal range for fertility. The probability of conception increases with increased sperm concentration up to 40 million/ml and so it is possible that the most exposed men could be less fertile than the least exposed."

She found that semen volume and total sperm count (which also affect a man's fertility) were associated with prenatal alcohol exposure; these were highest in sons whose mothers drank 1-1.5 drinks a week. The researchers could find no association between alcohol exposure and the movement and shape of the sperm or with any reproductive hormones such as testosterone.

Dr Ramlau-Hansen said: "Our finding that sons prenatally exposed to 1-1.5 drinks per week had higher semen volume and total sperm count compared to the least exposed group is not surprising and is quite a common finding when studying alcohol. It could indicate that small amounts of alcohol have a beneficial effect (for example, on the semen-producing tissue in the foetal testes), but, in fact, we believe this result may be biased by the characteristics of the women drinking small amounts of alcohol during pregnancy or by inaccurate reporting of alcohol consumption. Therefore, it is not possible to draw a firm conclusion from this result."

The researchers also investigated whether fathers' alcohol consumption had any effect. "We investigated the association between fathers' total alcohol intake and semen quality in the sons and found that paternal alcohol was not associated with semen volume or sperm concentration. This finding suggests that the observed associations between maternal alcohol consumption and sons' semen quality are not confounded by lifestyle factors that are shared by a couple, such as smoking," said Dr Ramlau-Hansen.

She concluded: "If further research shows that maternal alcohol consumption is a cause of reduced semen concentration in male offspring, then we are a bit closer to an explanation of why semen quality may have decreased during the last decades and why it differs between populations. If exposure to alcohol in foetal life causes poor semen quality in adult life, we would expect that populations with many pregnant women drinking, possibly heavily, in pregnancy would have lower fertility in comparison with populations of where pregnant women do not drink."

Emma Mason | EurekAlert!
Further information:
http://www.eshre.eu

More articles from Life Sciences:

nachricht Rainbow colors reveal cell history: Uncovering β-cell heterogeneity
22.09.2017 | DFG-Forschungszentrum für Regenerative Therapien TU Dresden

nachricht The pyrenoid is a carbon-fixing liquid droplet
22.09.2017 | Max-Planck-Institut für Biochemie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Rainbow colors reveal cell history: Uncovering β-cell heterogeneity

22.09.2017 | Life Sciences

Penn first in world to treat patient with new radiation technology

22.09.2017 | Medical Engineering

Calculating quietness

22.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>