Preprint: Post-viral fatigue following SARS-CoV-2 infection during pregnancy: a longitudinal comparative study, 2022, Oliveira, Nacul et al

It's a pity they didn't have an age matched group of non pregnant women as a control group so they could see whether pregnancy itself had any relevance to the findings.

 

It's good that someone thought to do this study - I assume there will be a followup.

Fatigue

Or indeed child care in those early months. I don't know many mothers who aren't exhausted up to the three month mark, and even the 6 month mark, especially if they also have a paid job. A lot of data was gathered, but they don't seem to have investigated the impact of major causes of normal fatigue e.g. employment, numbers of children under the mother's care, lack of family support

Assessing fatigue through answers to this question would be particularly hard for a first time mother whose life will have completely changed following the birth:

I didn't see any reference to PEM, or anything like it, which is a shame and surprising given Luis Nacul's involvement.

(The article has at least one thing wrong - reporting the fatigued percentages of G1 women as the fatigued percentages of all participants.)


Dropouts

That's a pretty low percentage. The supplementary table gives more information. Look at Group 1 - that's the women diagnosed with Covid during their pregnancy. 44% had one visit only - and yet the trial design aimed to have them assessed potentially 7 times. That surely puts a lot of uncertainty about the results.

Birth method
As an aside - What the hell is going on in Brazil with that rate of cesarean deliveries? More than 60%! In my country (NZ), the rate is less than 30%, and I'm surprised it is that high. Here's rates in Scandinavia which are in line with WHO recommended rates :

Surely a rate that high in Brazil is a waste of medical resources and is causing worse outcomes for the mother? If I was the Health Minister of Brazil, or even just in a women's rights group there, I'd be looking hard at what is going on and trying to get the situation changed. Ah, here's an article about the issue if you are interested in reading further, doesn't sound good.
The Atlantic - why most Brazilian women get c-sections

 

Anyway, back to the results of the study:



Note this is just for the G1 group, who got Covid during their pregnancy. Have a look at the definitions of fatigue. Only a handful of the 259 women were reporting fatigue that resulted them doing half or less than half as much as before the onset of fatigue. By 6 months after infection, only one woman was reporting fatigue that would not disappear with rest.

Without any assessment of PEM, I'm not sure that this tells us much at all.

So, I'm not sure that I'm reading it right, but I think this chart is saying, women who had a severe bout of Covid-19 during their pregnancy had a higher chance of remaining fatigued at the 90 day/three month mark than women with a milder illness. But it looks to me as though all the women with severe disease were recovered at the 210 day/7 month mark. Whereas it's the women with mild illness who had fatigue lingering out beyond that, even to the 330 day/11 month mark.

I think it's interesting that of these 178 women, none appear to have remained fatigued at the one year mark. Of course 178 women is a small sample to pick up cases of ME/CFS. But, there is no evidence that being pregnant while having Covid-19 results in a big risk of getting ME/CFS. I certainly wouldn't be concluding from this that a serious case of Covid-19 makes you more likely to get lingering post-viral fatigue out beyond the 6 month mark than a mild case.

I think the conclusion that the paper has made about the influence of illness severity on fatigue, and specifically post-viral fatigue, is not nuanced enough. It does not discriminate between the sort of fatigue we might expect in a woman who has gone through a difficult illness and pregnancy, versus a post-viral fatigue condition.