Clomid...breast enlargement in men?


New member
Just read some side effects of Clomid for men on some medical site and they listed breast enlargement as a possible side.

I didn't think that Clomid could do this/gyno. Does anyone know why this side is listed in medical literature for Clomid in regard to men using it?

i have never heard of that but it is a synthetic estrogen... i think they were speaking theoretically, but im not sure, post the article
Here's the article

Fertility Drugs for Men

• The drugs and how they work
• Is it for you?
• Length of treatment
• Success rate
• Side effects

Just as women need the right balance of hormones to ovulate regularly, men need certain hormones to produce healthy sperm. Surprisingly, the same substances control these reproductive functions in both men and women -- so the same fertility drugs that stimulate ovulation stimulate sperm production. The catch is that the drugs don't perform nearly as well for men (success rates are about a third of those for women), and the FDA hasn't yet approved them for use in men, though a specialist can prescribe them. Very few studies have been done on the effects of fertility drugs on men, and those few agree on just one thing: The drugs can help only men with specific hormonal imbalances.

The drugs and how they work

The two most popular fertility drugs for women, clomiphene and human menopausal gonadotropin (hMG) used with human chorionic gonadotropin (hCG), are also used to treat men with primary hypogonadotropic hypogonadism -- a hormone deficiency in the pituitary gland or hypothalamus that prevents the testicles from receiving the signal to make sperm.

Clomiphene (taken daily as a pill) prompts the pituitary gland to make luteinizing hormone and follicle-stimulating hormone, which tell the testicles to produce testosterone and possibly more sperm. Human Chorionic Gonadotropin ( Human Chorionic Gonadotropin (HCG) ) (injected two to three times a week, sometimes with hMG) prompts the testes to produce testosterone and sperm directly.

Is it for you?

Your doctor may prescribe fertility drugs if you have a hormonal imbalance (originating in the pituitary gland or hypothalamus) linked to a low sperm count; sometimes a doctor will also prescribe them for poor sperm quality and motility (its ability to move).

Length of treatment

For men, a cycle of clomiphene consists of taking one pill a day for three to six months, and a cycle of hCG means having two to three injections a week for six months. (If your body doesn't respond to hCG, your doctor may suggest that you also take hMG.)

Taking fertility drugs for longer periods doesn't improve your chance of success, so if you take one for more than three months and your partner doesn't get pregnant, your doctor may increase the dosage, switch you to another medication, or, most likely, suggest another kind of treatment. However, as long as your hormone levels stay normal, you can safely take clomiphene in low doses for six months to a year.

Success rate

Although success is far from guaranteed, fertility drugs can help jump-start your sperm production, boosting your count to 20 million or more (anything under 20 million is considered low). If the medication works, you won't have to think about undergoing a testicle biopsy to see what else might be wrong with your sperm.

Some studies cite an estimated 20 to 25 percent pregnancy rate for couples when the man has used fertility drugs. That's low compared to the rates for women on fertility drugs, which is 20 to 60 percent. But even the latter number loses some of its punch when you consider that it's about the same rate couples battling a low sperm count or poor sperm quality can expect for a spontaneous pregnancy with no treatment at all.

Side effects

In men, both clomiphene and hMG can cause temporary blurred vision, breast enlargement and tenderness, and weight gain. In rare cases, clomiphene can cause liver damage.
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Anyone know about the validity of this side effect of Clomid? I for one don't believe it and use Clomid quite a bit. I've never heard of a bodybuilder getting gyno from Clomid.

Bump for comments!

I've seen 'gynecomastia' listed as a possible side effect of clomiphene, but I don't really think it's possible since it's actually used to treat gynecomastia....

A few examples:

Acta Endocrinol (Copenh) 1980 Oct;95(2):177-80 Related Articles, Links

The effect of clomiphene citrate on pubertal gynaecomastia.

LeRoith D, Sobel R, Glick SM.

Clomiphene citrate 100 mg daily was used to treat 28 boys with pubertal gynaecomastia. Six failed to complete the course and of the remaining, 14 (64%) responded within 6 months of commencement of therapy. LH, FSH, testosterone and oestradiol levels rose during therapy. It is suggested that clomiphene affects gynaecomastia locally as an anti-oestrogen.


Am J Dis Child 1983 Nov;137(11):1080-2 Related Articles, Links

Clomiphene in the treatment of adolescent gynecomastia. Clinical and endocrine studies.

Plourde PV, Kulin HE, Santner SJ.

Twelve boys, aged 12 to 19 years, with persistent gynecomastia were treated with the antiestrogen, clomiphene citrate, at a dose of 50 mg/day by mouth for one to three months. The mean breast size decreased by 0% to 36%, with only five boys experiencing a reduction of greater than 20%. Five boys subsequently required reduction mammoplasty. Levels of urinary gonadotropins, serum testosterone, and estradiol increased significantly during therapy. Since the ratio of testosterone to estradiol remained unchanged during treatment, the antiestrogen effects were achieved primarily at the level of breast tissue. Clomiphene citrate in a dose of 50 mg/day resulted in only small decreases in persistent pubertal gynecomastia and was not a satisfactory medical therapy for the condition.

I did find this study, but the abstract is not available.

Fertil Steril 1978 Dec;30(6):713-5 Related Articles, Links

Case report: cystic gynecomastia in a male treated with clomiphene citrate.

Check JH, Murdock MG, Caro JF, Hermel MB.
There is a mention made of men being on clomide for 6 months to a year for fertility purposes. It may be the length of time that increases the risk factor. Bodybuilders are never on clomide for that length of time. Additionally, if this was a problem experienced by bodybuilders there would be anecdotal experiences posted all over the boards about it.
Nutrient-Nut said:
Just read some side effects of Clomid for men on some medical site and they listed breast enlargement as a possible side.

Sorry to bump an old thread, going through post cycle therapy (pct) stuff :)

I have read actually that clomid has been proven in some males to inexplicably raise estrogen levels.
I know the reason for this I believe. Because clomid is a selective agonist/antagonist and binds to the receptor, doctors weren't entirely sure in which tissues it would exert estrogen-like effects. Breast activity seems like a possibility given its structure but it just so happen (thank GOD) that it does not.