Psychological distress in pregnant women during the COVID-19 pandemic and measures of the structure of the foetal brain

Psychological distress in pregnant women

A study published in Communications Medicine looks at maternal psychological distress during the COVID-19 pandemic and structural changes of the human foetal brain.

Prof Ciara McCabe, Professor of Neuroscience, Psychopharmacology and Mental Health, University of Reading, said:

“This small preliminary study is an extension of the authors’ previous work linking fetal brain development and maternal stress.  The study shows brain differences between pre-pandemic and pandemic fetal development.  However the authors acknowledge that the developmental differences related to stress did not remain after multiple correction, suggesting other pandemic factors may be at play, for e.g., unknown exposure to covid-19.  However the long term implications of this type of work is yet unknown.  Follow up longer term studies are needed for this.  As the human brain develops rapidly in early childhood with many further changes in adolescence it will be interesting to see how pandemic fetal development affects these later developmental processes going forward.

Does the press release accurately reflect the science?

“Yes.

Is this good quality research?  Are the conclusions backed up by solid data?

“Yes.

How does this work fit with the existing evidence?

“Yes, this is an extension of work by the same group looking at stress and fetal brain development.

Maternal stress and fetal brain development.

Have the authors accounted for confounders?  Are there important limitations to be aware of?

“The brain developmental differences related to stress did not remain after multiple correction, suggesting other pandemic factors may be at play.  Plus any brain changes between groups may have been due unknown exposure to covid-19.

What are the implications in the real world?  Is there any overspeculation?

“The long term implications are unknown.

Should new mothers or pregnant women be worried?

“No, as the long term implications are unknown plus the human brain continues to develop a lot in childhoods early years and right through to adulthood.  Then more slowly from then on.

Is this study able to show what effects there might be of any observed brain structural differences, or don’t we know that from this

“No as they are fetal – you can see brain differences but this study can’t directly tell you how this might affect behaviour later on.

Does this study have long-term data or is it preliminary?

“No – it is preliminary.” 

Dr Nadja Reissland, Senior Lecturer in Psychology, Durham University, said:

“The study was well conducted with a good sample of pregnant women during COVID compared with a Pre-Covid sample.  In the literature however there are now also quite a few studies which show that the pandemic itself was perhaps not the main factor, rather social support plays a big role in how pregnant women fared during the pandemic.  Women who were supported coped well whereas women who were left on their own (e.g. to decide whether or not to take the vaccine, with reduced care, worries about partner being allowed to be present at the birth) fared worse.  One study published in Pregnancy and Childbirth (2022) reported a negative experience when they had to give birth during the pandemic especially during the first lockdown.  Given that COVID was present in the second lockdown the difference between first and second lockdown are of interest.  These results emphasise that the context of being pregnant and giving birth is of prime importance.  It is something the authors mention themselves in the limitations to their study.

“Another limitation is that maternal COVID status was not assessed independently.  Hence it is unclear if at least some of the women were COVID positive which might have influenced the results.  Nevertheless, this is an important study showing that stress and depression seem to play a role in brain formation.

Maternal COVID status

“These findings makes sense and could explain what we have found in many of our fetal studies showing that maternal stress, depression and anxiety affect fetal behaviour.  For example in our paper on fetal vision (Reissland et al 2020) we found that In contrast to other studies examining fetal reactions to prenatal light stimulation, without controlling for maternal factors (importantly maternal stress, depression and anxiety) that in fetuses at 33 weeks gestation, maternal anxiety and depression, and fetal growth factors (femur length) all had a significant effect on fetal reactivity to face-like compared to a non-face-like control light stimulus.  This calls into question some previously published results.

“In another study (Reissland et al 2018) we found that fetuses in the third trimester reacted differentially to sound and light stimulation depending on maternal mental health status with a 20% increase in fetal eyeblink for each unit increase in anxiety score and a 21% decrease in fetal eyeblink for each unit increase in depression score indicating that fetuses are affected differentially by maternal anxiety and depression.

“The current study makes clear that in fact maternal stress measured using PSS and depression measured using EPDS, two measures used in many of our studies, have an effect on fetal brain development and this goes someway to explaining our findings of differential behaviours by the fetus depending on maternal mental health status.”

Reference:

Reissland, N., Froggatt, S., Reames, E., & Girkin, J. (2018). Effects of maternal anxiety and depression on fetal neuro-development. Journal of Affective Disorders. 241, 460-474.

Reissland, N., Wood, R., Einbeck, J. & Lane, A. (2020). The effects of maternal mental health and prenatal attachment on fetal reactions to face-like light stimulation. EarlyHumanDevelopment151:105227 https://doi.org/10.1016/j.earlhumdev.2020.105227

Prof Carmine Pariante, Professor of Biological Psychiatry, Institute of Psychiatry Psychology & Neuroscience, King’s College London (IoPPN), said:

“The paper by Lu et al. presents some interesting findings of changes in the size of brain structures of developing foetus during the COVID pandemic, compared with a historical cohort the previous year. The sample size is relatively small, but these studies are difficult to complete and thus the authors should be commended for such an effort. Although the paper includes a multitude of statistical analyses, thus risking the occurrence of chance findings, in reality the findings are to be considered robust: the neuroimaging analyses uses advanced methods, and the described brain changes are consistent with what we already know about the effects of stress and mental disorders on the brain, including the effects of maternal stress or depression on the infant brains (although interestingly they cannot replicate well-known differences in the male and female infant brains).

“There are two main limitations that are worth considering. First, studies across historical cohorts are very difficult to interpret, especially when major social events occur, like in this study. The authors acknowledge that they do not measure “social isolation, financial insecurity, and nutritional changes”, which were massive factors during the pandemic. My opinion is that these factors will have had a more direct role in explaining these brain changes than just the subjective levels of mothers’ anxiety, and indeed some of the association between brain changes and maternal anxiety are statistically weak.

“The second limitation is that the paper does not present any neurological or behavioural assessment of the babies, which could have been easily carried out in the first few days or weeks after birth. These would have offered a clear interpretation of the true relevance of these brain size changes for babies’ mental life. So we don’t know from this study what impact, if any, these brain size changes might have on babies.”

‘Maternal psychological distress during the COVID-19 pandemic and structural changes of the human fetal brain’ by Yuan-Chiao Lu et al. was published in Communications Medicine at 16:00 UK time on Thursday 26 May 2022.

DOI: 10.1038/s43856-022-00111-w

Research finds that drinking even small amounts of alcohol while pregnant can cause harm

During pregnancy, women are told to avoid alcohol because there is no safe level of use.

New research has found that even very small amounts of exposure can lead to a baby growing up to experiment with alcohol at a very young age.

This behaviour is known as 'sipping', when a child has small sips from their mum or dad's drink, and while it might seem harmless, it increases their risk of problem drinking later in life.

For expectant parents, few issues have the ability to cause controversy like consuming alcohol while pregnant.

While women in the United States have been warned to avoid all alcohol during pregnancy, some research has found that small amounts of alcohol during pregnancy may be safe.

Now, new research finds that the safest option for pregnant women is to avoid alcohol all together.

After analyzing 23 previously published studies, researchers confirmed that drinking alcohol during pregnancy leads to children with poorer cognitive functions and increases the risk of lower birth weight.

“We wanted to look at all of the evidence from different types of studies, in a comprehensive way,” Luisa Zuccolo, PhD, study lead and senior lecturer in epidemiology at Bristol Medical School: Population Health Sciences, told Healthline.

“We also found that for two outcomes, cognition and birth weight, there were enough studies of different type agreeing with each other, indicating a harmful effect of alcohol in pregnancy,” Zuccolo said. “This was not surprising, but it adds another piece to the jigsaw of evidence on this important public health question.”

The study was published Wednesday in the International Journal of Epidemiology.

First time different study designs were compared

Researchers say this is the first time results from a number of different study designs were compared relating to the effect of drinking alcohol during pregnancy.

“The trickiest thing in this field is to be able to have comparable groups of pregnant women, and children, who only differ by alcohol consumed during pregnancy — this is how we can tell if alcohol causes the outcomes, rather than just being correlated with them,” said Zuccolo.

The analysis looked at both traditional studies like randomized controlled trials (RCT) and alternative strategies that involved comparing children in the same family whose mothers reduced or increased alcohol consumption between pregnancies.

Zuccolo explained that they used study designs with different methods and assumptions to make these groups comparable, as would be done in an experiment, so “we can be more confident in our conclusions, provided the results point in the same direction.”

Previous research findings not as ‘robust’

Previous research on drinking during pregnancy was done using observational studies. This is when participants have been exposed to a risk factor and researchers don’t try to change who has or hasn’t been exposed.

“Our present study was the first to assess together the evidence from disparate sources, most of which included women drinking in moderation. The results are more robust than other reviews,” Zuccolo confirmed.

While the research was comprehensive, Zuccolo admits it was limited in its ability to establish the amount of alcohol that leads to a negative outcome.

Alcohol industry minimizes harmful effects of alcohol

A recent study finds that alcohol industry-funded websites routinely omit or misrepresent evidence on the risks of alcohol consumption during pregnancy. According to researchers, this may “nudge” women toward continuing to drink during pregnancy. The findings suggest that alcohol industry-funded bodies can increase risk to pregnant women by spreading misinformation.

“Alcohol is a teratogen, meaning it causes anomalies. Alcohol affects the developing fetal brain, heart, facial features, and impairs normal growth,” said Dr. Kecia Gaither, director of perinatal services at NYC Health + Hospitals/Lincoln.

Gaither explained that drinking during pregnancy increases the risk for fetal alcohol syndrome (FAS), a disorder characterized by symptoms that include:

neurological issues like cognitive delay

hearing issues

cardiac abnormalities

hyperactivity

facial deformities

“These affects occur along a spectrum, and babies and children so affected grow up into adults so affected,” Gaither emphasized. “To my knowledge there is no threshold of drinking alcohol during pregnancy known so as to provide a guide as to how much will cause the syndrome or not. Therefore, women are advised not to imbibe at all during pregnancy.”

Source:- journals.elsevier.com + jsad.com + abc.net.au

Probiotics found to improve nausea and vomiting in pregnancy

Researchers at the University of California, Davis have found that probiotics significantly improve the symptoms of pregnancy-related nausea, vomiting and constipation. Their findings were published in the journal Nutrients.

During pregnancy, hormones like oestrogen and progesterone increase, bringing about many physical changes. These increases can also change the gut microbiome, which likely affects the digestive system functions and causes unwanted symptoms like nausea, vomiting and constipation. The researchers set out to determine whether supplementing with a probiotic could be beneficial for gastrointestinal function during pregnancy.

A total of 32 participants took a probiotic capsule twice a day for six days and then took two days off; they then repeated the cycle. The probiotics were available over the counter and mainly contained Lactobacillus, a type of good bacteria. Each capsule contained approximately 10 billion live cultures at the time of manufacture.

The researchers found that taking the probiotic significantly reduced nausea and vomiting. Nausea hours (the number of hours participants felt nauseous) were reduced by 16%, and the number of times participants vomited was reduced by 33%. Probiotic intake also significantly improved symptoms related to quality of life, such as fatigue, poor appetite and difficulty maintaining normal social activities, as scored by questionnaires. Probiotics were also found to reduce constipation significantly.

“Over the years, I’ve observed that probiotics can reduce nausea and vomiting and ease constipation; it’s very encouraging that the study proved this to be true,” said Albert T Liu, lead author on the study and a professor of obstetrics and gynaecology. “Probiotics have also benefited many of my other patients who weren’t in the study.”

Participants also contributed faecal specimens before and during the study, which were analysed to identify the type and number of microbes and the different by-products of digestion. This allowed the researchers to examine whether biomarkers in the faecal specimens corresponded with more severe nausea and assess how the probiotics affected participants who began the study with different baseline biomarkers.

One finding was that a low amount of bacteria that carry an enzyme named bile salt hydrolase, which generates bile acid to absorb nutrients, was associated with more pregnancy-related vomiting. Probiotics increase bile salt hydrolase-producing bacteria, which may explain why the supplements decreased levels of nausea and vomiting.

Another finding was that high levels of the gut microbes Akkermansia and A. muciniphila at the beginning of the study were associated with more vomiting. The probiotic significantly reduced the amount of those particular microbes and also reduced vomiting. This suggests Akkermansia and A. muciniphila may be reliable biomarkers that can predict vomiting in pregnancy.

The researchers caution that due to the small sample size, further studies will be needed to confirm the effects of the probiotics. They are also keen to test the impact of probiotics in other areas, such as for the reduction of nausea and vomiting caused by chemotherapy in cancer patients.

SOURCES:- 

pmj.bmj.com

en.wikipedia.org

journals.lww.com

hopkinsmedicine.org

bmcpregnancychildbirth.biomedcentral.com

nature.com

onlinelibrary.wiley.com