The Search
A computerized literature search of the following bibliographic databases (from 1966 or closest to present) was conducted: Cancerlit, Cinhal, Current Contents, Premedline, and MEDLINE. An Ovid Vendor and Polaris interface were used. Mesh heading and text words (for databases without Mesh headings, i.e., Premedline), adjacency operators and truncation were employed. A preliminary search was used to maximize potential keywords.
A study filter was not applied, nor was the search limited by language or year of publication.
The search produced four cohort studies of relevance. The highest-quality study is analyzed in this article: "Risk of cancer after use of fertility drugs with in-vitro fertilization."[6] The authors proposed to examine "whether cause of infertility or exposure to fertility drugs to induce superovulation was associated with an increased cancer risk." We will focus on the latter part of the objective (i.e., whether superovulation is associated with an increased risk of ovarian cancer). The cited article is an extension of a previous study published by the authors in 1995.[7]
The Venn study is a prospective cohort study that attempts to determine the relative risk of the exposed cohort versus the general population by means of standardized incidence ratios. The authors also compared the exposed infertile cohort to an unexposed infertile cohort. We are concerned with this latter comparison. The relative risk (0.51, [confidence interval 0.17, 1.52]), however, is not clearly stated. It has therefore been calculated from the crude numbers, using a random effects model, as presented below.
Semin Reprod Med. 2003;21(1) © 2003 Thieme Medical Publishers
Cite this: Ovarian Cancer and Fertility Medications: A Critical Appraisal - Medscape - Feb 01, 2003.
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