Monday, October 26, 2009

Low blood vitamin D and birth by c-section

Tonight I'm prepping for the class I teach at UConn on Wednesday nights and the topic of the evening is vitamin D. Since the text I'm teaching out of is a bit outdated with respect to the recent findings on vitamin D, I had to do some extra researching to provide accurate info to my students. In my search, I came across this interesting study on the relationship between low blood vitamin D levels and c-section deliveries. So, because my brain is engulfed in thoughts on pregnancy and delivery, I was quite happy to share this all with you.

Association between vitamin D deficiency and primary cesarean section

J Clin Endocrinol Metab. 2009 Mar;94(3):940-5

BACKGROUND: At the turn of the 20th century, women commonly died in childbirth due to rachitic pelvis. Although rickets virtually disappeared with the discovery of the hormone vitamin D, recent reports suggest vitamin D deficiency is widespread in industrialized nations. Poor muscular performance is an established symptom of vitamin D deficiency. The current U.S. cesarean birth rate is at an all-time high of 30.2%. We analyzed the relationship between maternal serum 25-hydroxyvitamin D [25(OH)D] status, and prevalence of primary cesarean section.

METHODS: Between 2005 and 2007, we measured maternal and infant serum 25(OH)D at birth and abstracted demographic and medical data from the maternal medical record at an urban teaching hospital (Boston, MA) with 2500 births per year. We enrolled 253 women, of whom 43 (17%) had a primary cesarean.

RESULTS: There was an inverse association with having a cesarean section and serum 25(OH)D levels. We found that 28% of women with serum 25(OH)D less than 37.5 nmol/liter had a cesarean section, compared with only 14% of women with 25(OH)D 37.5nmol/liter or greater (P = 0.012). In multivariable logistic regression analysis controlling for race, age, education level, insurance status, and alcohol use, women with 25(OH)D less than 37.5 nmol/liter were almost 4 times as likely to have a cesarean than women with 25(OH)D 37.5 nmol/liter or greater (adjusted odds ratio 3.84; 95% confidence interval 1.71 to 8.62).

CONCLUSION: Vitamin D deficiency was associated with increased odds of primary cesarean section.


Lorien said...

That is an interesting study, but c-section rates are also at an all time high because of the cascade of interventions pushed on women by care providers. There are some great books out there you might find interesting, like "Pushed" which I've read and "Born in the USA" which I've not yet read.

Anonymous said...


Our neighbors recently purchased a stand-up tanning system called the Sunsplash Renew (electronic ballast as opposed to a noisy magnetic one with high EMF; 90 percent UVA, 10 percent UVB; also produces visible red light in the 633 nm range) and offered to allow us (my pregnant wife and I) to come over and use it as we wished.

Basically I am wondering if 2 to a maximum of 3 sessions per week with the lamp (each lasting no more than 5-10 minutes maximum and adjusting duration as skin tolerance adapts) would be a perfectly safe way to maintain optimal vitamin D levels (as determined by 25(OH) D3 testing) during Winter.

This tanning lamp exposure would be in lieu of high-dose oral supplementation but in addition to the cholecalciferol consumed when eating things like egg yolks and the 500 IU's in the multi-vitamin she takes.

Basically you're one of the most knowledgeable and reasonable minds out there, so I wanted to get your take before deciding whether or not my wife and I should take our neighbors up on their generous offer.

My intuition and common sense tells me that very moderate exposure (as opposed to extended baking seen with some who use lamps)shouldn't pose any risk and that it is a fine option if it keeps D levels up in Winter. Plus the issue of high EMF is removed, since there is no magnetic ballast. But I'd appreciate any advice you have to offer on this topic.

Cassandra Forsythe said...

Hi Anonymous

I'm not entirely sure, but can find out. I'll do some digging, read what the experts say and get right back to you. Thanks for the great Q!

Lorien! Thank you! I bought those two books today. The more and more I think about this study, the more I see low vitamin D linked with everything under the sun. In this case, it seems like a bit of a long stretch. However, maintaining ideal vitamin D levels does have many benefits for bone health, cancer protection and hormone balance. Hopefully this will be a standard measure prior to and during pregnancy. Thank you again!

Anonymous said...

I'd be very appreciative of that, Cassandra.

What makes it difficult these days is figuring out who has an agenda (often trying to make a buck and/or manipulate folks) when reporting on material and who is trustworthy.

You're in that rare category of someone who is able to properly interpret research and is also 100-percent transparent and honorable................when I state it like that, I almost make you sound as mythical as a unicorn!


Katie Munger said...

How much vitamin D do you suggest than women take per day (I am nursing so does that change your recommendation?). I just realized that the prescription multivitamin that my doctor has me on does not have any vitamin D in it, so I have been taking some extra. You are the expert so maybe you can shed some light on how much extra is enough?
Katie Munger

Cassandra Forsythe said...

Hi Anonymous

In reading over some new research today, a researcher in sunny California reported that most of the patients he measured (who spent time in the sun), did not have adequate vitamin D levels in the blood. So, sun and light exposure might not actually make as much difference as we hope. It could depend on other factors too, such as the cholesterol content of your blood - which is converted to vitamin D in a series of steps and your ability individually to make this conversion.
This bed you have might be different than just sun exposure. Do check your blood levels before and after using for a few months it without doing anything different with diet or supps and let us know what happens. Each person is different, so if it works for you and your wife, that's wonderful :)

Hi Katie
Good question. In the last publications (Oct 09) on requirements for lactation/non-lactation states, depending on blood levels, women were recommended to take anywhere from 800 IU to 2,000 IU of vitamin D. If your levels are low (<32ng/mL), go with 2,000. If they are in a good range (some experts recommend above >50ng/mL), 800 IU, in addition to what you have in your diet, would be an ideal dose.

Anonymous said...


I definitely will continue to use blood work to monitor levels, but I always wonder (in reference to people who get sun exposure) if they are exposing sufficient amounts of skin.

I am fortunate in that I can get exposure right around the noon to 1 pm period and am in a location where I can go outside in just shorts, to allow for as much exposure as possible. This still might leave a lot of folks lagging, but probably far less so than someone exposing only their arms an face.

Additionally, I don't avoid using soap all over when showering after sun exposure, so as to limit any interference with vitamin D absorption (from reading, I was lead to believe that absorbing what is produced in the skin can take a fair amount of time).

I suppose what I truly wanted to ask you was if you perceive brief usage of the lamp 2-3 times a week maximum was risky in relation to skin cancer. Some people seem to think that any exposure to these is terrible, but I can't see very reasonable and controlled exposure to be inherently risky.

And I was under the impression that if I can keep vitamin D levels in the optimal range that this would also protect against melanoma.

So basically if the skin cancer risk from using the lamp for brief sessions, I was indeed going to use it and track levels by testing to determine its effectiveness. And if it failed to keep things up to par, I was going to switch to a D3 nanospray or emulsion (I've heard Life Extension Foundation offers a good one).

My intuition tells me that the lamp would be no different than the sun, in that controlled exposure should not pose any undue risk, but constantly hearing how the lamps are invariably cancer-causing death traps still gives me pause. But again, it is often hard to tell whether this reputation arose because of a very real and widespread risk or because of the EMF produced by some commercial beds plus sessions that were excessive in duration and frequency.


Cassandra Forsythe said...

Hi Ben

I'm not 100% sure about the answer to that question; yes, vitamin D does have cancer-protecting effects, but I'm not sure how risky or not the light beds really are. It's hard to find research about it and if you do, you wonder if it's biased or not.

As far as D3 emulsions, I use the one by Biotics research called Bio-D emulsion forte. My D levels jumped from 25 to 50 in 2 months with one drop per day (of 2,000 iu)

Anonymous said...


Thank you very much for all of your feedback (especially the info about your experience with D3 emulsion) It is always greatly appreciated.

I suppose I will take a chance on the light (along with having regular tests done), and bank on moderate exposure not causing me any major issues..............of course there's a good chance that moderate exposure may not keep levels where I need them to be, in which case I will cut the light out and go running to purchase the emulsion you recommended.

Thanks again for being so willing to share your thoughts and answer so many questions on this blog. It's a privilege to visit your website.