Scanning electron microscopy of Dalkon Shield tails.

Scanning electron micrographs of Dalkon Shield tails removed from asymptomatic patients show a variety of microbes and debris throughout their entire length. Apparently, even in undamaged tails, bacterial flora thrive in the protein-rich environment within the multifilament tail. The presence of microbes in the portion of the tail beyond the double knot indicates that an alternative mechanism of microbial transport can occur. Since transient endometritis often occurs immediately after insertion of intrauterine devices, microbes may come in contact with both exposed ends of the multifilament tail and be drawn into the tail by capillary action from the uterine environment down the tail toward the double knot as well as upward from the vagina. Such microorganisms could serve as an inoculum for infection.