排卵誘発剤は癌発生の危険を増加させない　

1999/4/26　ロイター　　以前排卵誘発剤により卵巣癌が増加すると報告されたが、イスラエルの研究では治療後平均18年経た婦人には卵巣癌や乳癌の発生増加は認められなかった。しかし、さらに長期間の追跡が必要としている。

Fertility drugs not linked to increased cancer risk

NEW YORK, Apr 26 (Reuters Health) -- Contradicting previous studies, a new study from Israel found no link between fertility drugs and an increased risk of ovarian and breast cancer.
But the research team also cautions that more long-term study is needed to reach a definitive answer.
The study included 1,197 infertile women treated between 1960 and 1984 at Soroka University Hospital in Beer-Sheva, Israel, who were followed for an average of 18 years after treatment.
Of those infertile women not treated with fertility drugs, there was no increase in ovarian, breast or any other type of cancer.
Of the 780 women given drugs such as the ovulation-stimulating drugs clomiphene citrate and hMG, there was no increase in ovarian cancer, according to the report in the May issue of the journal Fertility and Sterility.
There was, however, an increased risk of breast cancer in women who had one to two cycles of clomiphene citrate and no more than 1,000 milligrams of the drug. However, the risk was not elevated in women who had three to five cycles or even in those with more than six cycles of treatment, or those given more than 1,000 milligrams of the drug.
``Therefore, it is very unlikely that the use of fertility drugs might have contributed to the development of the disease,'' conclude Dr. Gad Potashnik, of the Soroka University Medical Center and colleagues.
Overall, nine women who had one to two cycles of clomiphene citrate developed breast cancer and one developed ovarian cancer, compared with the three to four cases of breast cancer and less than one case of ovarian cancer that would be expected to be diagnosed in the 276 women.
``On the basis of these observations, we conclude that the use of fertility drugs among infertile women is not associated with an excessive risk of developing breast cancer,'' the authors write.
However, the authors caution that because of the long period of time it takes for cancer to develop, the women need to be followed for many more years to confirm the preliminary results.
The average age of the women studied was 44, and they must be followed well into their 60s before the authors can make ``a definitive statement about the risk of ovarian and breast cancers among infertile women and after the use of fertility drugs,'' they conclude.
SOURCE: Fertility and Sterility 1999;71:853-859.