Can taking Vitamin D supplements help me get pregnant?

The effect of Vitamin D on fertility is a widely-discussed topic on TTC (trying to conceive) forums - but will Vitamin D *really* boost or improve your chances of conceiving? We asked GP Dr Philippa Kaye to find out...


On Trying To Conceive (TTC) forums, including MadeForMums’ own, we’ve seen plenty of women ask: can taking daily Vitamin D supplements help you get pregnant?


There are loads of theories floating about the web – and a few self-reported success stories from women who’ve *finally* fallen pregnant after introducing Vitamin D supplements, much like the one we’ve shared below.

But, what’s the scientific view on Vitamin D and fertility? Is there any hard proof that Vitamin D can play a role in helping women conceive?

We decided to do a bit of digging, and here’s what we think you need to know…

One mum’s ‘Vitamin D fertility success story’

MFMer Charchar27 took to our forum to share her journey from Polycystic Ovary Syndrome (PCOS) diagnosis to a natural pregnancy – which she reckons has a lot to do with her recent addition of Vit D supplements.

She began: “I was diagnosed with PCOS at 17, didn’t have my first period until I was 24 and between then and now (4 years) I had a total of 10 periods!

“Me and my partner have been together 5 years and never used any contraception. We took the view that it would never happen naturally and if it did it would be a miracle so why prevent it. 

“Anyway, a year and a half ago we started the process of getting fertility treatment but for one reason or another, it kept getting put on hold and we felt like we were never going to get there.

“I started to do some research into natural supplements I could take and came across a lot of research and information into Vitamin D and fertility.

“After a lot of reading I thought, what harm could it do? And ordered myself a high dosage of vitamin D, and started taking them daily.

“Lo and behold, 3 months later, I fell pregnant naturally!! This could be a complete coincidence but with how irregular I was I really feel it played a part.”

Obviously, Charchar27’s situation is unique to her, and, as she says, she knows fine well it could be a coincidence.

Still, it’s hard to deny her story…

Can Vitamin D deficiency affect fertility?

Firstly, if you’re having fertility struggles, you need to start by making an appointment with your GP.

It’s important to explore why this isn’t happening for you. Sadly, for many couples, the reason won’t be as simple as a Vitamin D deficiency.

That said, there IS some evidence in both animals and humans to suggest that Vitamin D may affect fertility and IVF success rates, Dr Philippa Kaye tells us.

So, it’s definitely worth considering taking a Vitamin D supplement if you’re a bit deficient, something your GP will be able to tell you with a simple blood test.

Did you know pretty much everyone in England, Scotland, Wales and Northern Ireland is recommended to take one, anyway?

“Vitamin D insufficiency is really common in the UK, to the extent that everyone is recommended to take a supplement of 400 IU (10 micrograms) of Vitamin D per day from approximately the end of September to April,” says Dr Kaye.

“Pregnant women are also advised to take this dose throughout the whole of pregnancy, so it may be worth starting while you are trying to conceive.”

Can Vitamin D help women with PCOS get pregnant?

There’s also been a few small-scale studies looking at the role of Vitamin D in helping to regulate the periods of women with PCOS.

One report, from the Indian Journal of Medical Research, takes an overview of such studies, and claims:

“In particular, Vitamin D and calcium supplementation in addition to metformin therapy in women with PCOS could result in the beneficial effects on menstrual regularity and ovulation.”

Though very interesting, the report also notes that the studies were so small in size that results are not conclusive, adding:

“Further research with high quality randomised controlled trials is warranted to establish the impact of vitamin D supplementation on the management of PCOS.”

Like Dr Kaye says, though, most people in the UK need a Vitamin D supplement regardless.

So, if you have PCOS, are trying to get pregnant, and your doc finds you are a bit deficient in Vitamin D, we don’t see ANY reason why you shouldn’t give the supplements a shot!

We would add that you should try, as hard as it is, not to get your hopes up too high 💛

Share your story

Have you fallen pregnant not long after introducing a Vitamin D supplement? Perhaps you’ve tried it and it had no affect? Tell us in the comments below or over on Facebook – we’d love to hear your stories.

Images: Getty Images

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