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Wagamaga OP t1_j7gdzkx wrote

Women who take extra vitamin D during their pregnancy are more likely to have a ‘natural’ delivery, according to new research.

The study, published in the Journal of Public Health, analysed results from the MAVIDOS trial which involved 965 women being randomly allocated an extra 1,000 International Units (IU) per day of vitamin D during their pregnancy or a placebo.

Analysis showed that 65.6% of women who took extra Vitamin D had a spontaneous vaginal delivery, or “natural” delivery, compared to 57.9% in the placebo group.

Fewer women from the vitamin D group had an assisted delivery (13.2%) compared with the placebo group (19.4%).

https://www.standard.co.uk/news/health/vitamin-d-women-university-of-southampton-university-hospital-southampton-nhs-foundation-trust-national-institute-for-health-and-care-excellence-b1058304.html

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InTheEndEntropyWins t1_j7gf127 wrote

>Analysis showed that 65.6% of women who took extra Vitamin D had a spontaneous vaginal delivery, or “natural” delivery, compared to 57.9% in the placebo group.

That would be a much better title.

The current title is almost meaningless.

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theajharrison t1_j7gio6t wrote

The article doesn't use the term "natural"

And if you were legitimately curious, the answer to what is the definition of outcomes could be answered by just reading the first two paragraphs of the abstract.

> ...mode of delivery [categorized as spontaneous vaginal delivery (SVD), instrumental (including forceps and vacuum extraction) or Caesarean section]

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SaltZookeepergame691 t1_j7gmmpw wrote

The major ‘caveat’ here is that this is a post hoc analysis of a trial that was done to look at something else, and you have to consider that this was one aspect of many they looked at - hence, they findings are only hypothesis generating, and require confirmation.

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Ok_Lifeguard_6508 t1_j7gzxh3 wrote

Those effect sizes are quite small. If be surprised if they were statistically significant.

−1

aradil t1_j7h0td3 wrote

I know you just threw out a number there, but if we’re talking single digit billions, that’s such a small percentage of health care dollars that it would barely register.

If the average person in the US costs $13k a year in health care, scaled down to the individually, billions of dollars would be like… tens of dollars per person of that $13k.

The US spends trillions of dollars a year on healthcare.

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aradil t1_j7h26d8 wrote

My point was that that dollar amount is meaningless without context of how much is being spent.

I also don’t think it would save billions of dollars in, say, Canada, which would still be only a modest couple of percentage of points of savings.

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SaltZookeepergame691 t1_j7h61lf wrote

It’s significant (and the 95% CI indicates it is reasonably so), but this is a post hoc analysis of an outcome they already ‘knew’, in a trial that already had many outcomes, making this result at pretty high risk of being a chance false positive. This is probably why they don’t give actual p values - the findings are hypothesis generating, not confirmatory.

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lakeland_nz t1_j7i07wr wrote

Absolutely.

And yes, the subset of women that choose to take Vitamin D are almost certainly not representative of the population. That said, there was a treatment and a placebo group who thought they were taking Vitamin D, so by comparing those two groups we can start to see the effect of Vitamin D.

In this case 65.6 vs 57.9 giving a relative risk between 1.02 and 1.25. 1.02 > 1, so my reading is that the Vitamin D resulted in a statistically significant decrease in relative risk. That's very exciting.

Why does it work? Would this also apply to the general population? There are plenty of good follow-up questions.

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slantedangle t1_j7i99la wrote

Wouldn't that depend on what decisions were made by who?

What if doctors recommended an assisted birth but a pregnant woman insisted on a natural birth? How does vitamin D affect that decision?

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SelarDorr t1_j7ilh7a wrote

why would you write a title like this, with the percentage of natural births for the treatment group but not the control? Has much less meaning as an empirical number in my opinion.

​

the placebo group was 58%, resulting in a relative risk ratio of 1.13.

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buzmeg t1_j7illsf wrote

Except that Vitamin D and Folic Acid are known to be atagonistic.

So, if you dose too much Vitamin D, it decreases Folic Acid and places your baby at risk of birth defects.

As always, these things are a balance.

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SelarDorr t1_j7ilxie wrote

i dont see that as a major caveat. you can have a primary study with multiple secondary outcomes, in which the results of the secondary outcomes are just as meaningful as a study in which those outcomes are the primary.

the results of this analysis are still of a randomized double blind placebo controlled trial that directly compared the treatment group to the placebo group for the outcome in question. the fact that these results were not the primary focus of the study does not change its significance.

if it were a case where sample selection for the primary outcome somehow added a confounder for some of the secondaries, i see an argument there. but as far as i can tell, this wasn't the case here.

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leplen t1_j7io778 wrote

Eh, the more secondary outcomes you allow the more you run the risk of multiple comparisons. If the p-valur is low enough I'm fine with it, but otherwise you get into green jelly beans cause acne territory.

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BertnErnie32 t1_j7isv5s wrote

I've always said that women getting more D are more likely to give birth

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Lupicia t1_j7iwgje wrote

So. I've had both kinds of C-sections.

Planned cesarian like with my twins can be good, but emergency ones are traumatic, especially after a 'failed' labor. This double whammy is very, very physically draining. It took me months to be able to sit up and years to regain full use of my abs (which you use for everything). Then add on the emotional regret and shame of not being able to go 'natural like women are built to do'. And shame from the attending pediatrician for pushing too long. Like I had a choice.

Yeah no obstructed labor followed by emergency C-section is worse (ETA: in my experience) than my kidney stones, worse than broken major bones IMHO.

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Lupicia t1_j7ixq4k wrote

Same! Sorry you're dealing with kidney stones. They suck. If it's any consolation nothing beats kidney stones except that craziness, not even "regular" labor or C-sections or surgery or IUDs. Kidney stones are crazy.

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rougewitch t1_j7iyxcb wrote

Ive had 2 C-sections and chronic kidney stones- stones are worse bc they are like time bombs that will go off whenever they feel like it. The chronic back pain doesn’t help either.

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porkminer t1_j7j4i2l wrote

I'm going to go out on a limb and agree that prolonged pain and difficult recovery mixed with emotional turmoil are absolutely worse than kidney stones. I have chronic stones, several times per year I get stones that barely pass. I'm lucky if I only get 1 or 2 too large to pass. I still don't believe that my suffering equates to yours. Pain is subjective, however, so comparisons are a good way to start an argument.

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Lupicia t1_j7j7lzq wrote

Yikes friend. Have you talked with a urologist? That's not okay. I've passed four or five and that was more than enough to get me referred. I'm surprised if you haven't been urged to get a more effective treatment for recurring stones or at least an analysis of the stone type so you can help dissolve them. Unless you have already?

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porkminer t1_j7j84mq wrote

Yeah, my diet is exceptional strict between my kidney issues and diabetes. Most of them pass with moderate discomfort. Usually only some painful twinges followed by a persistent ache for a few days. The larger ones get toradol and an antibiotic sometimes. The really big ones get a short hospital visit. Urologist and endocrinologist. I also have a cardiologist though that's preventative, not worth the risk with my other issues and family history.

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SaltZookeepergame691 t1_j7jdudj wrote

If you don’t have any hypothesis before you do the trial to statistically “test” (ie through null hypothesis testing) any significant result (regardless of multiple comparisons control) you generate is - by definition - hypothesis generating.

I don’t mean that the trial itself isn’t robust. It is. But the finding is not enough on its own to say “this is real”.

2

Ok-Heat1513 t1_j7jjor7 wrote

Does vitamin d make a child’s head smaller?

−1

newpua_bie t1_j7jlab7 wrote

They're not that low everywhere. For example, in Finland (my birth country) the rate is about 83%, while also having one of the world's lowest infant & maternal mortality. US probably just does C-sections more than medically justified (more $$$?)

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Eckleburgseyes t1_j7jmqa1 wrote

Ladies who love the D have babies. This is the way

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egg_suit t1_j7jnoj3 wrote

I mean how are u supposed to give birth without the d anyway

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Accomplished_Eye9769 t1_j7k5wqh wrote

The overall percentage of "natural" births is slightly higher than 65.6%. This implies that Vitamin D causes more complicated births...

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SaltZookeepergame691 t1_j7kcgnv wrote

This is a post hoc analysis. This was NOT a named secondary! It explicitly says so in the paper, and it’s why I explicitly said it was a post hoc analysis…

For your info, from the reg record:

>Primary outcome measure

>Neonatal whole body bone area, bone mineral content and bone mineral density assessed by dual energy x-ray absorptiometry (DXA) within 10 days of birth.

>Secondary outcome measures

>1. Neonatal and childhood anthropometry and body composition (weight, length and skinfold thickness measurements), assessed within 48 hours of birth

>2. Women's attitude to pregnancy vitamin D supplementation (qualitative study; assessed in main study only). Methodology and timepoints of assessment not yet defined as of 03/03/2008

>3. Childhood bone mass at 4 years

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Wandering_Scholar6 t1_j7ko9z1 wrote

Likely part of larger problems with the population being deficient in D

FYI if you live in certain areas you probably need vitamin D. The line shifts depending on your skin tone. Try some even if you aren't pregnant, you might notice a difference in your mood and/or health

Obligatory IMNAD talk to your doctor

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SaltZookeepergame691 t1_j7l2zkk wrote

Indeed. It’s nice that they are frank about this in the discussion but worrying that they say nothing about it in the abstract. A good journal wouldn’t publish this without an explicit warning that it was a post hoc analysis. Violation of basic CONSORT guidelines.

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juancn t1_j7lrjt8 wrote

Compared with? It’s a meaningless stat by itself.

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Quetzalcoatle19 t1_j7qgqm8 wrote

There wasn’t? I don’t even need to read the article for that. Cesarean is done because of a physical impossibility of trying to push the baby through the vaginal canal, if it’s being done, you already do not have other options, and they do not allow you to just opt for a c section because it’s dangerous compared to regular birth.

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