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Male and female infertility

After multiple early miscarriages an ectopic pregnancy and two expensive failed attempts at IVF I was interested to find that B12 deficiency plays a role in fertility. Looking back through my medical records I found that I had never been tested for B12 deficiency and my high homocysteine test result was ignored. 


I was never asked if B12 deficiency or pernicious anaemia was present in my family (it is). It appears that none of the clinicians involved in my care had any idea of the consequences of B12 deficiency and the effect on fertility. How can clinicians find something they have not been trained to see?

The cost of one ampoule of hydroxocobalamin in the UK is now under £2, a drop in the ocean in comparison to the cost of IVF.

I discovered that I have MTHFR and MTRR genetic mutations and these mutations affect my ability to metabolise both B12 and folate. 

It may be that you, like me, require an active form of folate rather than the folic acid generally prescribed.

My hope is that those who may have an undiagnosed deficiency go on to have a chance of natural conception with the help of information provided here. For help on what to do next please click here. We have also developed an app to help determine your risk of B12 deficiency.

If you are struggling to access correct treatment and you feel you need personalised help, please see the contact page for more information. 

Information below supplied with kind permission of Sally M. Pacholok R.N. and Dr. Jeffrey J. Stuart.

For infertile couples life often becomes an endless round of expensive (and often expensive) fertility treatments. For couples who conceive babies but suffer miscarriages, trying to become pregnant again can be frightening, turning into an anxiety-ridden ordeal that often ends once again in failure. There are dozens of common causes of male and female infertility . . . but there is another risk factor that is often overlooked, even by infertility specialists. That problem is B12 deficiency.


Male infertility

Many investigations into male infertility find low sperm motility or a low sperm count to be the cause. How many of these men are tested for B12 deficiency?

Male infertility and B12 deficiency

In about 40% of cases, a couples inability to conceive is due to male infertility. Here again, Vitamin B12 plays a significant role and again that role is generally overlooked by doctors.

The link between male infertility and insufficient B12 levels first became commonly known in the 1980's when researchers reported a study in which 27% of men with sperm counts less than 20 million were able to increase these counts to more than a 100 million after receiving 1,000 mcg per day of vitamin B12. This research was pursued by scientists in Japan, who published a series of clinical and laboratory studies showing B12's beneficial effect on sperm counts.

Impotence and Erectile dysfunction

When symptoms such as ED or incontinence involve B12 deficiency, early treatment is crucial. The longer the problem continues, the more difficult treatment will be- and eventually the damage will be irreversible.

B12 deficiency may also cause impotence in men. B12 deficiency can result in erectile dysfunction (ED) because the nerves in the penis can become damaged making it impossible to achieve or maintain an erection. We routinely see general practitioners, internists and urologists prescribing medications for patients with ED. We also see them blaming other disease processes, such as diabetes, for ED impotence, or incontinence. Typically they fail to contemplate that B12 deficiency may be causing or or contributing to these problems. This is a huge and tragic mistake, because B12 deficiency is more common as we age, especially in older adults who suffer from ED.

Click here to read relevant medical journals.


Female infertility

Married for 7 years a thirty three year old woman kept hoping for a baby and wondering why she couldn't conceive. She also felt increasingly weak, had trouble walking, and noticed that she couldn't remember things well.

Her doctors's drew a blank, until one spotted signs of macrocytic anaemia and referred her to a haematology clinic. There, doctors diagnosed her with B12 deficiency and started her on injections of the vitamin.

Within three months she felt vastly better mentally and she could walk normally again. Within six months, she became pregnant. Her long years of waiting for a child ended when she delivered a healthy baby girl.

Other doctors have also reported successful pregnancies in once infertile women following therapy for B12 deficiency. Yet often, sadly, this deficiency is overlooked even by infertility specialists until women have undergone months or even years of unsuccessful treatment. They experience disappointment after disappointment, when treatment with proper B12 replacement and high dose B12 therapy might have solved their problem. 

B12 deficiency and Miscarriage: Far More Common Than Doctors Think

A recurring theme in medical literature is that B12 deficiency is a fairly rare cause of miscarriage or stillbirth. The evidence, however, suggests otherwise. One recent study, for instance, compared thirty-six women who'd suffered recurrent foetal loss to forty women who'd carried healthy babies to term. The researchers found that 31 percent of the women who'd lost several babies had high homocysteine levels. (Elevated homocysteine is caused by low levels of folate, B12 and/or vitamin B6, and is easily treated with these vitamins).

Sixteen percent of the women who'd suffered recurrent foetal loss carried two copies of the MTHFR gene that causes abnormally high homocysteine levels, and three of the women had overt B12 deficiency. 

Click here to read more.

Click here to read relevant medical journals.

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