探花直播 of Cambridge - birth

Tales from the edge of modern fertilities

fpjl2 — Tue, 15 Dec 2020 14:21:15 +0000

A major research project sees sociologists situated at emerging hot spots of reproductive change, investigating the new 鈥榟aves and have-nots鈥� in our fertility futures.聽聽聽聽聽聽

Surviving birth

lw355 — Thu, 10 Dec 2020 09:00:28 +0000

Researchers at one of the busiest maternity hospitals in the world aim to help more women survive complications giving birth.

Nature鈥檚 epidural: Genetic variant may explain why some women don鈥檛 need pain relief during childbirth

cjb250 — Tue, 21 Jul 2020 15:00:21 +0000

Childbirth is widely recognised as a painful experience. However, every woman鈥檚 experience of labour and birth is unique, and the level of discomfort and pain experienced during labour varies substantially between women.

A collaboration between clinicians and scientists based at Addenbrooke鈥檚 Hospital, part of Cambridge 探花直播 Hospitals NHS Foundation Trust (CUH), and the 探花直播 of Cambridge sought to investigate why some mothers report less pain during labour.

A group of women was recruited and characterised by the team led by Dr Michael Lee from the 探花直播鈥檚 Division of Anaesthesia. All the women had carried their first-born to full term and did not request any pain relief during an uncomplicated vaginal delivery. Dr Lee and colleagues carried out a number of tests on the women, including applying heat and pressure to their arms and getting them to plunge their hands into icy water.

Compared to a control group of women that experienced similar births, but were given pain relief, the test group showed higher pain thresholds for heat, cold and mechanical pressure, consistent with them not requesting pain relief during childbirth. 探花直播researchers found no differences in the emotional and cognitive abilities of either group, suggesting an intrinsic difference in their ability to detect pain.

鈥淚t is unusual for women to not request gas and air, or epidural for pain relief during labour, particularly when delivering for the first time,鈥� said Dr Lee, joint first author. 鈥淲hen we tested these women, it was clear their pain threshold was generally much higher than it was for other women.鈥澛�

Next, senior co-author, Professor Geoff Woods, and his colleagues at the Cambridge Institute for Medical Research sequenced the genetic code of both groups of women and found that those in the test group had a higher-than-expected prevalence of a rare variant of the gene KCNG4. It鈥檚 estimated that one approximately 1 in 100 women carry this variant.

KCNG4 provides the code for the production of a protein that forms part of a 鈥榞ate鈥�, controlling the electric signal that flows along our nerve cells. As the joint first author Dr Van Lu showed, sensitivity of this gatekeeper to electric signals that had the ability to open the gate and turn nerves on was reduced by the rare variant.

This was confirmed in a study involving mice led by Dr Ewan St. John Smith from the Department of Pharmacology, who showed that the threshold at which the 鈥榙efective鈥� gates open, and hence the nerve cell switches 鈥榦n鈥�, is higher 鈥� which may explain why women with this rare gene variant experience less pain during childbirth.

Dr St. John Smith, senior co-author, explained: 鈥� 探花直播genetic variant that we found in women who feel less pain during childbirth leads to a 鈥榙efect鈥� in the formation of the switch on the nerve cells. In fact, this defect acts like a natural epidural. It means it takes a much greater signal 鈥� in other words, stronger contractions during labour 鈥� to switch it on. This makes it less likely that pain signals can reach the brain.鈥�

鈥淣ot only have we identified a genetic variant in a new player underlying different pain sensitivities,鈥� added senior co-author Professor Frank Reimann, 鈥渂ut we hope this can open avenues to the development of new drugs to manage pain.鈥�

鈥淭his approach of studying individuals who show unexpected extremes of pain experience also may find wider application in other contexts, helping us understand how we experience pain and develop new drugs to treat it,鈥� said Professor David Menon, senior co-author.

探花直播research was support by the Addenbrooke鈥檚 Charitable Trust, the National Institute for Health Research Cambridge Biomedical Research Centre, Wellcome, Rosetrees Trust and the BBSRC.

Reference
Lee, M.C. et al (2020). Human labour pain is influenced by the voltage-gated potassium channel Kv6.4 subunit. Cell Reports; 21 July 2020; DOI: 10.1016/j.celrep.2020.107941

Women who do not need pain relief during childbirth may be carriers of a key genetic variant that acts a natural epidural, say scientists at the 探花直播 of Cambridge. In a study published today in the journal Cell Reports, the researchers explain how the variant limits the ability of nerve cells to send pain signals to the brain.

This [variant] acts like a natural epidural. It means it takes a much greater signal 鈥� in other words, stronger contractions during labour 鈥� to switch it on. This makes it less likely that pain signals can reach the brain

Ewan St. John Smith

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Mother and newborn baby

探花直播text in this work is licensed under a Creative Commons Attribution 4.0 International License. Images, including our videos, are Copyright 漏探花直播 of Cambridge and licensors/contributors as identified.聽 All rights reserved. We make our image and video content available in a number of ways 鈥� as here, on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms.

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Online atlas explores north-south divide in childbirth and child mortality during Victorian era

sc604 — Tue, 15 May 2018 07:36:56 +0000

探花直播Populations Past website is part of the Atlas of Victorian Fertility Decline research project based at the 探花直播 of Cambridge, in collaboration with the 探花直播 of Essex. It displays various demographic and socio-economic measures calculated from census data gathered between 1851 and 1911, a period which saw immense social and economic change as the population of the UK more than doubled, from just under 18 million to over 36 million, and industrialisation and urbanisation both increased rapidly.

探花直播atlas allows users to select and view maps of a variety of measures including age structure, migration status, marriage, fertility, child mortality and household composition. Users can zoom in to an area on the map and compare side-by-side maps showing different years or measures.

探花直播maps reveal often stark regional divides. 鈥淕eography plays a major role in pretty much every indicator we looked at,鈥� said Dr Alice Reid from Cambridge鈥檚 Department of Geography, who led the project. 鈥淚n 1851, more than one in five children born in parts of Greater Manchester did not survive to their first birthday. In parts of Surrey and Sussex however, the infant mortality rate at the same time was less than a third that number.鈥�

While there are broad north-south divides in most of the maps, patterns at a local level were more complicated: in the northern urban-industrial centres such as Manchester, infant and child mortality were high, while many rural areas of the north had mortality rates as low as rural areas of the south. And in London, there is a sharp east/west divide in fertility, infant mortality, the number of live-in servants, and many other variables.

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探花直播researchers also found that different types of industry were often associated with different types of families: in coal mining areas where there was little available work for women, women married young and often ended up with large families. In contrast, women in the textile-producing areas of Lancashire and Yorkshire had more opportunities to earn a wage, and perhaps consequently, had fewer children on average.

There are also big differences over time. 探花直播period saw a sharp drop in the number of women who continued to work after marriage, for instance. In 1851, more than a third of married women were in work across large sections of the country, but by 1911, only a tiny fraction of married women worked outside the home, apart from the textile-producing areas of the Northwest.

鈥淭his might be associated with the rise of the culture of female domesticity: the idea that a woman鈥檚 place is in the home,鈥� said Reid.

Across the Western world, fertility rates have declined over the past 150 years. Gaining a historical perspective of how and why these trends have developed can help improve understanding of the way in which modern societies are shaped.

Between 1851 and 1911, England and Wales changed from countries where there were variable fertility and mortality rates to countries where rates for both were low. Child mortality and fertility fell from the 1870s, together with a fall in illegitimacy, but infant mortality did not start to fall until the dawn of the twentieth century.

As part of the project on fertility decline, the researchers have investigated fertility in more detail. For the first time, they have been able to calculate age-specific fertility rates for more than 2000 sub-districts across England and Wales during this era, and their results challenge views on the way that fertility fell.

鈥淚t鈥檚 long been thought that the fall in fertility was achieved when couples decided how many children they wanted at the outset of their marriage, and stopped reproducing once they had reached that number,鈥� said Reid. 鈥淲hile this may have happened in more recent fertility transitions, such as in South-East Asia and Latin America, when reliable contraception was widely available, it was not a realistic scenario in the Victorian era.鈥�

鈥淲e don鈥檛 find age patterns of fertility which would be produced by this type of 鈥榮topping鈥� behaviour during the Victorian fertility decline,鈥� said Reid鈥檚 collaborator Dr Eilidh Garrett from the 探花直播 of Essex. 鈥淪uch behaviour would show up as a larger reduction of fertility among older women, but instead, women of all ages appear to have been reducing their fertility.鈥�

As well as the interactive maps, the Populations Past site provides a variety of resources for researchers, teachers and students at all levels. 探花直播research was funded by the Economic & Social Research Council and the Isaac Newton Trust.

A new interactive online atlas, which illustrates when, where and possibly how fertility rates began to fall in England and Wales during the Victorian era has been made freely available from today.聽

In 1851, more than one in five children born in parts of Greater Manchester did not survive to their first birthday. In parts of Surrey and Sussex however, the infant mortality rate at the same time was less than a third that number.

Alice Reid

Populations Past

Early childhood mortality rates in 1851 (left) and 1911 (right). 探花直播highest rates are in red and the lowest in blue.

探花直播text in this work is licensed under a Creative Commons Attribution 4.0 International License. For image use please see separate credits above.

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Opinion: Losing your virginity: how we discovered that genes could play a part

Anonymous — Fri, 15 Apr 2016 08:13:05 +0000

As far as big life decisions go, choosing when to lose your virginity or the best time start a family are probably right up there for most people. It may seem that such decisions are mostly driven by social factors, such as whether you鈥檝e met the right partner, social pressure or even your financial situation. But scientists are increasingly realising that such sexual milestones are also influenced by our genes.

In a new study of more than 125,000 people, published in Nature Genetics, we identified gene variants that affect when we start puberty, lose our virginity and have our first child. This is hugely important as the timing of these events affect educational achievements as well as physical and mental health.

Children can start puberty at any time between eight and 14-years-old. Yet it is only in recent years that we have begun to understand the biological reasons for this. Through studies of both animals and humans, we now know that there鈥檚 a complex molecular machinery in the brain that silences puberty hormones until the right time. At this point, chemical messengers secreted from the brain begin a cascade of events, leading to the production of sex hormones and reproductive maturity.

Human genetics studies have identified many genes that are linked to individual differences in the onset of puberty. There are broadly two approaches used to map such genes 鈥� studies of patients affected by rare disorders that affect puberty and large-scale population studies. 探花直播former is helpful because it can investigate gene variants that cause extremely early or delayed/absent puberty.

In previous research, we used population studies to survey a large number of individuals using questionnaires and then genome-wide association studies to scan these same participants for common genetic differences. We could then assess whether the participants' reported age at puberty was related to particular gene variants. In this way, we have in a number of studies identified more than 100 such variants, each modifying puberty timing by just a few weeks. However, together they contribute substantially.

We now understand that both nature and nurture play a roughly equal role in regulating the timing of puberty. For example, studies have consistently shown that obesity and excessive nutrition in children can cause an early onset of puberty.

Genetic factors

However, we know far less about the biological and genetic factors behind the ages that we first have sexual intercourse or have a first child. This is because previous research has focused more on environmental and family factors than genetics. But the launch of UK Biobank, a study with over half a million participants, has greatly helped to fill this lack of knowledge.

In our new study, we used this data to survey some 125,000 people in the same way as in the puberty studies. We found 38 gene variants associated with the age of first sexual intercourse. 探花直播genes that we identified fall broadly into two groups. One category is genes with known roles in other aspects of reproductive biology and pubertal development, such as the oestrogen receptors, a group of proteins found on cells in the reproductive tract and also in behaviour control centres of the brain.

If you went through puberty early you are more likely to have many children in life. Tom Adriaenssen/wikimedia, CC BY-SA

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探花直播other group includes genes which play roles in brain development and personality. For example, the gene CADM2, which controls brain activity and also has strong effects on whether we regard ourselves to be risk-takers. We discovered that this gene was also associated with losing your virginity early and having a higher number of children throughout life. Similarly, the gene MSRA, linked to how irritable we are, was also associated with age at first sexual intercourse. Specifically, people who are more irritable typically have a later encounter. However, more research is needed to show exactly how these genes help regulate the timing of the reproductive milestones.

We were also able to quantify that around 25% of the variation in these milestones was due to genetic differences rather than other factors.

Implications for public health

An important reason why we study reproductive ageing is that these milestones impact reproductive outcomes and also broader health risks. Epidemiological studies show that individuals who go through puberty at younger ages have higher risks of many diseases of old age, such as diabetes, heart disease and breast cancer. Similarly, first sexual intercourse at an earlier age is linked to a number of adverse behavioural, educational and health outcomes.

Using a statistical genetics approach called Mendelian Randomisation, a technique that helps clarify the causal relationship between human characteristics, these studies can tell us whether such epidemiological associations are likely to be causal rather than just random associations. We managed to show that early puberty actually contributes to a higher likelihood of risk-taking behaviours, such as sexual intercourse at an earlier age. It was also linked to having children earlier, and having more children throughout life.

These findings, along with previous studies linking early puberty and loss of virginity to social and health risks, back the idea that future public health interventions should aim to help children avoid early puberty, for example by diet and physical activity and avoiding excess weight gain. Our findings predict that this would have benefits both on improving adolescent health and educational outcomes and also for future health at older ages.

John Perry, Senior Investigator Scientist, 探花直播 of Cambridge and Ken Ong, Group Leader of the Development Programme at the MRC Epidemiology Unit, 探花直播 of Cambridge

This article was originally published on 探花直播Conversation. Read the original article.

探花直播opinions expressed in this article are those of the individual author(s) and do not represent the views of the 探花直播 of Cambridge.

John Perry and Ken Ong (MRC Epidemiology Unit) discuss how聽sexual milestones are聽influenced by our genes and how this can impact on broader health risks.

探花直播text in this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Images, including our videos, are Copyright 漏探花直播 of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways 鈥� as here, on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms.

For image use please see separate credits above.

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