A bioassay procedure is described for quality control testing of various disposable items used in routine IVF procedures. This bioassay is performed over 4 days and uses the survival of human sperm in vitro at room temperature to assess which products are suitable for use. New products were tested for cytotoxicity using a general screening method and subsequent batches of every suitable item tested to detect interbatch variation. Products were considered suitable or unsuitable for use depending upon a calculated sperm survival index. Two main types of product were found to be cytotoxic, namely certain brands of syringe and surgical gloves, the common feature of both being the presence of rubber components. The bioassay was also used to investigate further the cytotoxic effect of the powdered and starch-free surgical gloves. The cytotoxic substances from both types of surgical glove were readily transferred to an embryo replacement catheter by touch, and washing of the gloves reduced this effect only moderately. The bioassay has proved inexpensive and convenient but more importantly it has been invaluable for detecting potential sources of cytotoxicity before they are introduced into a standard IVF protocol.