B12d, periods & clomid: Just wondering... - Pernicious Anaemi...

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B12d, periods & clomid


Just wondering if anyone has experienced any of the following and can maybe help? I have b12 deficiency, not diet related and not hereditary as far as I know so no idea why I have it. Anyway, I'm self-injecting twice a week since April this year and have been feeling pretty much ok.

My periods stopped in Jan 2017, following all the tests there was no conclusion why... after my first b12 injections in April I had a period straight away but then no more. I've started clomid to encourage me to ovulate, so have just had my 3rd period on this. But... all my b12d symptoms are coming back.

So basically I'm a bit confused, could I be losing b12 through my periods making me deficient again? If b12d stopped my periods then why haven't they come back as normal after I started injections? Does clomid have any affect on b12 levels?

If anyone has any pearls of wisdom to offer I'd be grateful :) thank you

12 Replies

Sorry I can’t answer your question but I just wanted to mention that before I was diagnosed with an overactive thyroid (Graves disease), 10 years before I had PA, my periods had stopped. I understand that was because of the thyroid problem.

Both Graves and PA are autoimmune illnesses and as such are linked.

I assume you’ve had your thyroid levels, including antibodies, tested?

Thanks for your reply - yes I have had the tests and they were "normal" over 6 months ago but got a GP appt early Dec when I'm going to ask for all the tests again as a review.


not sure if this would be relevant but progesterone based 'pill' is known to affect B12 absorption. I personally found that it wiped me out completely which wouldn't have been anything to do with the amount of B12 in my blood but would seem to be about creating circumstances for me in which some processes just didn't run efficiently. More B12 did help ... but cutting the hormone down to a bare minimum to do the job probably helped more.

I think we probably muck around with hormones at our own peril. There are a lot of grey areas with them and interactions aren't fully understood.

Looks like clomid can have a lot of side-effects but nothing obviously linked to B12 coming up - you could try speaking to your pharmacist and may be it just isn't the right treatment for you.

Thanks so much, that's very helpful. The clomid is only short term atm so I guess I'll see if I pick back up again once I've stopped taking it... and yes, messing with hormones is a bad business :(

Hi Gambit62! It's interesting to hear your reply - all my much more serious absorption problems have been since I was put on a POP. I'm desperate to stay on it though as it is the only thing that manages my migraines which can last for 3 weeks at a time without it - but it would be good to know how it affects absorption. I even take my pill sublingually as I get migraines if I don't an suspect I must be getting more progesterone into my system via my mouth than my digestive tract.

Hi Yellowkangaroo! I had a spell on Clomid a long time ago as part of fertility treatment and it made me feel terrible. This was when I was diagnosed with CFS which I'm sure was B12d. I thought it was just the hormone but this could easily have been a worsening of my deficiency.

If you are B12d then you are likely to have raised homocysteine levels. This in turn will have an impact on fertility. If you are trying to get pregnant you may have to increase your B12 levels further and take supporting supplements - a broad spectrum multivitamin and mineral supplement plus extra folate, potassium, magnesium and iron - to make it work optimally to get your homocysteine levels down.

Good luck!

Thanks so much... have started the extra vits and here's hoping there's an improvement... I'm planning on a couple of months off clomid now to see what happens to the b12d symptoms.


"I have b12 deficiency, not diet related and not hereditary as far as I know so no idea why I have it."

Have you looked at these links?

Risk Factors for PA and B12 Deficiency




NICE guidelines Coeliac Disease (2015 version)


Coeliac Blood Tests


Nitrous Oxide


H Pylori infection


Internal parasites eg fish tapeworm?

B12 books I found useful

"What You Need to Know About Pernicious Anaemia and B12 Deficiency" by Martyn Hooper

Martyn Hooper is the chair of PAS (Pernicious Anaemia Society). Book is up to date with UK b12 guidelines.

"Living with Pernicious Anaemia and Vitamin B12 Deficiency" by Martyn Hooper

Has several case studies.

"Could it Be B12?: An Epidemic of Misdiagnoses" by Sally Pacholok and JJ. Stuart (USA authors)

Very comprehensive with lots of case studies.

PAS (Pernicious Anaemia Society)

Based in Wales, UK.


PAS tel no +44 (0)1656 769717 answerphone

PAS support groups in UK


B12 Deficiency Info website


I am not medically trained.

Thanks so much for your reply... I have finally got an appt with the GP next week to ask for full bloods to be done for any other deficiencies, and a referral to a gastro to see if any bowel issues causing it. I tested negative for coeliac in April. Heres hoping the gp cooperates!!


" I tested negative for coeliac in April"

Did you have both these tests?

1) tTG IgA

2) Total IgA

tTG IgA test is checking for a particular type of antibody to gluten.

Total IgA test is checking for which patients have IgA deficiency. Patients with IgA deficiency are unable to make the antibodies to gluten that tTG IgA test checks for and will test negative on tTG IgA test even if they have Coeliac disease.

If you have not had the Total IgA test, I don't see how GP can be certain you do not have Coeliac disease.

Prior to having tests for Coeliac disease, did GP explain that you need to be eating plenty of gluten each day for several weeks before testing for Coeliac? If you weren't eating much gluten then your antibody results may have been negative because there was not enough gluten for your body to produce lots of antibodies.

Coeliac disease and fertlity


Coeliac UK Helpline 0333 332 2033

Have you got copies of all your blood test results? I learnt to always do this after being told everything was normal on more than one occasion and then finding abnormal and borderline results on the copies.

Glad to read you are seeing a gastro specialist as they may be able to pick up signs of gut damage from Coeliac, PA, H Pylori etc.

Some details in next two links may be upsetting to read.

Link about B12 and Fertility


Link about B12 and Pregnancy


I think fertility issues are mentioned in all three books listed in my first post.

More B12 info.....

B12 and Blood Tests

What to do next


Blood tests




Full Blood Count and Blood Film



Folate Deficiency


Iron Studies


Thyroid Problems

"yes I have had the tests and they were "normal" over 6 months ago"

Have you seen actual results or were you just told they were normal? These days I don't trust what I am told about results unless I have a copy of results in my hand.

Some UK GPs will only do TSH test. Did you have all these tests?



Probably worth putting your thyroid results on the Thyroid UK forum on HU.

PA testing

Were you ever tested for PA (Pernicious Anaemia)?

In UK, recommended diagnostic test for PA is an Intrinsic Factor Antibody (IFA) test. Have you checked your results to see if you had an IFA test ?

IFA result is not always reliable, it's still possible to have PA even if IFA result is negative.

This flowchart explains how PA and Antibody Negative PA can be diagnosed in UK.

Flowchart from BSH Cobalamin and Folate Guidelines


If you're in UK, did GP follow process outlined by flowchart? In some areas of UK, Gps may be following outdated local B12 guidelines.

If you think PA may be a possibility then worth considering joining and talking to PAS (Pernicious Anaemia Society).


I am not medically trained.

Hi Yellow Kangaroo! I don’t have experience with your medication but I know that my periods were very very light and sporadic before I started on the b12. Now I’m on b12 they’re much heavier, more regular and I need to inject daily to keep the PA symptoms away during that time of the month. The PA definitely effects my cycle.

Thanks, I wonder if daily injections for a while would help me... It's all such a trial and error thing! Wish I could just know what was going on instead of taking this and that medication which probably isn't helping anything!

Unfortunately I can't help you either but thought I would share my experience.

I started taking the mini pill (which is well known for stopping periods in a lot of people who take it). My period stopped shortly after and I never thought anything off it. 2 years later I was diagnosed with PA and my b12 level was 16, I got 4 monthly injections for a few months and about 3 weeks ago I got a small period and a week ago I got another small one (completely unheard of for me previously).

Not sure if my period is going to actually come back, if it was gone because of my severe deficiency or just due to the pill I take. I guess I'm partially in the same boat as you in not knowing only time will tell for me! I hope you get your answer soon xo

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