Search our site

Custom Search

Thursday, 2 April 2020

How much do unborn babies sleep? (Things We Don’t Know about Pregnancy Series #16)

We can’t measure the brain activity of a human foetus – not whilst they’re inside their mother. But we’re really interested. What happens to a baby’s brain as it’s developing, and what does this tell us about our own and the developing process of sleep?

EEG (electroencephalogram) reading via Wikipedia Commons.
Researchers into brain activity have performed EEG (electroencephogram) exams on premature babies, and monitored eye movement in the womb to learn about sleep cycles, although big errors with these kinds of measurements are common. They have, however, detected REM (rapid eye movement) sleep from around 7 months, when the brain cycles in and out of restful and REM (rapid eye movement) sleep every 20 to 40 minutes. From 7 months onwards, foetuses mostly sleep (90-95% of the time at 32 weeks, 85-90% by 37 weeks). After it develops, REM sleep increases and increases, reaching a lifetime high of 12 hours a day just before the baby is born.

Very little is known about foetus sleep before this. For example, we don’t know if sleep and sleep cycles suddenly or more gradually develop with the foetal brain. New research into lambs has shown that foetuses enter a dreaming-like brain state weeks before REM sleep starts[1]. As well as learning more about sleep, this study could help us figure out how the brain develops and when it is most at risk.

Equally, neurons in the brain develop much earlier, with those responsible for sleep present long before REM sleep is seen.

Friday, 20 March 2020

Caesareans (Things We Don’t Know about Pregnancy Series #15)

Historically, a caesarean section was a life or death operation. When a birth started to go wrong, the question was who to save – the mother, or the baby? Luckily, the maternal mortality rate for pregnancy has dropped to around 0.007% in the UK in 2017 (down from 0.09% in just 1952[1]), and caesarean sections are now considered only slightly more risky than vaginal births (death risk is 3 times higher[2], but this may be because a number of caesareans are only carried out in emergencies). Caesareans may also reduce the risk of complications in some cases. It used to be that having a caesarean once meant further babies always had to be delivered this way – but that’s no longer true: for women who have previously had a caesarean section, choosing an elective one for a subsequent baby over a vaginal birth reduces the risk of complications or consequential health problems (such as womb damage) from 1.8% to 0.8%[3]. However, risk overall is small.

Caesareans now account for 26.2% of births in the UK[4], but there is still a lot we don’t know about them, especially how they might affect babies later in life.

Caesarean by Salim Fadhley via Wikipedia Commons.

Saturday, 14 March 2020

Climate change, glacial recession and mammal communities

By now, we are probably all familiar with the alarming fact that the polar ice caps are melting, and we’ve probably all seen the pictures of starving, stranded polar bears on thin pieces of sea ice. Scientists often look to the cryosphere – or the frozen water part of the Earth, such as ice caps, glaciers, areas of snow, and ice shelves – to understand the progression of climate change and predict how things may change in the future.

Changing climates have impacted the cryosphere for millions of years, and massive ice sheets have repeatedly advanced and retreated throughout history. The recession and advancement of these walls of ice has had an enormous impact on landscapes and the distribution of species, and while there have been many studies investigating how historical glacial recession has impacted current species distribution, little is known about how current species distribution is impacted by present day glacial recession.


Example of a tidewater glacier in Glacier Bay National Park. Johns Hopkins Glacier. ©

Wednesday, 26 February 2020

Baby Brain (Things We Don’t Know about Pregnancy Series #14)

Around eight weeks of pregnancy, I started forgetting the names of things.

Some know it as tip-of-tongue syndrome, and it’s definitely not new to pregnancy for me – it’s just worse.

Scissors via Wikipedia Commons.
No wonder I struggled with vocabulary in languages: looking for a pair of scissors, I will do the “scissor gesture” with my fingers and ask “Where are the …?” … “You know, the …?” It sounds odd coming from a writer, but it’s honestly true. I forget words easily. Nouns. These are obviously the least well-coded information at my disposal: after all, I can gesture or describe what I mean – even draw, if I need to, so this was the most easily lost content. Or that’s what I think was happening.

Other women have reported losing track of conversations, being absent-minded, and struggling with tasks such as reading comprehension.

The literature disagrees when it comes to the phenomenon known as “baby brain”. Is it real, or just a figment of women’s imaginations?

Wednesday, 12 February 2020

POPs

What are POPs?


There’s increasing concern about the growing mass of our discarded plastics – yet not because of their direct effects on wildlife (e.g. entanglement), but because plastics could be a crucial vector for the transport of key environmental contaminants: persistent organic pollutants, or POPs.

There are many thousands of POP chemicals, originating from agriculture, combustion processes, industrial syntheses, and products such as flame retardants, plasticisers and antimicrobials. In fact, our understanding and classification of them is ever evolving. They’re named not because of their chemical groups, but because of their behaviour. As the name “persistent organic pollutants” suggests, they’re long-lived and harmful.

Plastic debris on a beach. By epSos.de (Flickr).

What chemicals are we talking about?


Mosquito – By Alvesgaspar via Wikipedia Commons.
Typical culprits include DDT, polynuclear aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), halogenated flame retardants, and polybrominated diphenyl ethers (PBDEs). Although DDT is now banned in most countries, it’s still permitted in some places with a high incidence of malaria to fight off mosquitoes[1].

POPs are polluting and persistent because of certain properties, such as their solubility, reactivity and volatility.

Thursday, 6 February 2020

Vitamins and Supplements (Things We Don’t Know about Pregnancy Series #13)

Is it a safe and good idea to take vitamins whilst pregnant? One thing’s for certain – it’s the norm.

Bacteria. Public Domain.
Whilst scientists have shown that taking certain specific vitamin supplements can protect you against diseases to which you are at risk, taking high, regular doses of multivitamins is actually proven to increase your risk of heart disease or cancer[1]. We don’t know why – it could be because of the fibre, or the various digestive pathways food goes through in your body – but swallowing a broccoli vitamins tablet just doesn’t do the same as eating a broccoli. It may also mean you are missing out on foods rich in other stuff your body needs, perhaps things we haven’t even discovered yet. Then there’s your microbiome: we still understand relatively little about this, but we know you can alter the microbial constitution of your gut through diet and use of supplements.

Overall, a varied diet is recommended as the most healthy one – supplementing where necessary.

Thursday, 30 January 2020

Determining the Sex of a Baby (Things We Don’t Know about Pregnancy Series #12)

“And do you know… what it is?” they ask.

They mean the sex of our unborn baby, of course.

There isn’t much you can find out about who your unborn baby is, but you can know their sex. Or can you?

Often misnamed as “gender”, sex primarily relates to the organs a person presents with, but we already know that it’s more complex than that.

Chromosomes via Wikipedia Commons.
For a long time, we believed that sex was determined by a single chromosomal pair: XX or XY, but recent research has shown that the expressions of a bunch load of other genes is important too. For example, genes known as “enhancers” regulate the expression of genes that drive the development of physical sex characteristics. This means you can develop testes if you have an extra copy of the enhancers, even if you have two X chromosomes, or develop ovaries if you’re missing them, even if you are XY. The enhancers were found amongst the set of DNA formally known as “junk DNA”. These findings imply that observed biological sex and genetic sex may actually be different in some cases.

Tuesday, 21 January 2020

Adipogenesis – the making of fat

How Are Fat Cells Formed?


Our entire bodies originate from a single cell. Once it starts dividing, it kick-starts a multiplication process that lasts our whole lives. This ‘starter’ cell is a stem cell; a biologically programmable template for any other cell. They are responsible for everything, including our hearts, minds and waistlines.

Wait, waistlines?

Yes, this is determined by adipocytes, or white fat cells, in a process known as adipogenesis. There are six roughly defined phases of adipogenesis, but within them are a multitude of molecular processes, and explaining how they work poses a considerable challenge to scientists.

Fat, by Bigplankton via Wikipedia Commons.

Sunday, 12 January 2020

Silent Miscarriage (Things We Don’t Know about Pregnancy Series #11)

Miscarriage is a common medical complication that leads to the loss of a pregnancy before 23 weeks, and affects one in four women during their reproductive lifetime. Depending on how early or late it happens, it can have bigger or smaller impacts on a woman’s physical and mental health.

But why does it happen? Is it mostly to do with lifestyle, or genetics? Is there something you can do to prevent it? And how can we get early warnings of silent miscarriages – the ones you never even knew had happened?


If you’ve ever been pregnant – miscarriage or not – you’ll probably have wondered about these things, and worried about them, as I have. Whilst the chance of miscarriage drops off rapidly with time, stillbirth and postnatal foetal death are still classed as late pregnancy losses, and do happen from time to time, meaning there is no good time to truly forget about it.

Chances of miscarriage drop as pregnancy progresses. © TWDK. Data from: datayze.com

Saturday, 4 January 2020

The Thalidomide Scandal (Things We Don’t Know about Pregnancy Series #10)

In 1953, a new drug was made, and by 1957 it was on the market. In the six years that followed, over 10,000 children in 46 countries were born with congenital deformities[1]. The disaster was known as the thalidomide scandal, and led to serious reforms in drug regulation and monitoring worldwide.

What happened?

Thalidomide was prescribed for insomnia, anxiety, asthma, hypertension, migraine, and morning sickness. Doctors thought that it was very safe because taking an overdose simply cast the drinker into a prolonged sleep – and did not cause death. It was also non-addictive. Nobody tested it in pregnant women or animals.

Then, in 1961, two doctors independently called out statistically high numbers of congenital abnormalities in “thalidomide babies” – 20% where the normal rate is 1.5% (or a bit higher, depending on your source)[2].

Thalidomide babies. Image via Wikipedia Commons.