Umbilical cord transection to induce fetal demise prior to second-trimester D&E abortion.

OBJECTIVE: Induction of fetal demise via transabdominal injection has been used to facilitate second-trimester abortion but requires a second procedure and has associated risks. The method of amniotomy, cord transection and documentation of fetal asystole immediately prior to dilation and evacuation (D&E) is an alternative approach; however, characteristics of this method have not been described. STUDY DESIGN: This descriptive report from a single center involves a large case series of D&Es ranging from 16 to 23 weeks of gestation. Umbilical cord transection (UCT) was attempted immediately prior to D&E in 407 cases, which were reviewed to determine success, time to fetal asystole and complications. RESULTS: Both UCT and asystole were achieved in 100% of cases. Mean time from UCT to asystole was 3.35±2.11 min. When compared to cases performed at less than 20 weeks of gestation, mean time to asystole was slightly longer in the ≥20-week group (3.7±2.4 min vs. 3.1±1.9 min; p=.008). Few patients had minor (4.6%) or major (0.3%) complications; time to asystole was not associated with complications. CONCLUSIONS: Umbilical cord transection immediately prior to D&E is a feasible, efficacious and safe way to induce fetal demise without performing additional procedures. IMPLICATION STATEMENT: This study demonstrates the feasibility, effectiveness and safety of utilizing umbilical cord transection to induce fetal demise in a large cohort. This method is an alternative to other feticidal procedures.

FISHing for chick genes: Triple-label whole-mount fluorescence in situ hybridization detects simultaneous and overlapping gene expression in avian embryos.

Multi-color whole-mount in situ hybridization is a powerful technique for comparing the spatial expression patterns of two or more genes in developing embryos. We have developed an amplified triple-label whole-mount fluorescence in situ hybridization (FISH) protocol that permits detection of three different mRNAs in a single embryo. Our protocol uses simultaneous in situ hybridization to haptenylated riboprobes, followed by sequential antibody detection using anti-hapten antibodies conjugated to horseradish peroxidase, and the tyramide signal amplification (TSA) fluorescence detection system. Conventional fluorescence microscopy identifies areas of overlapping gene expression at the tissue level, whereas confocal fluorescence microscopy permits single-cell resolution and differentiates specialized cell types within a given tissue. This protocol will provide researchers engaged in the use of FISH with a solid starting point for adapting their own in situ hybridization protocols, either alone or in combination with immunohistochemistry or green fluorescence protein colocalization.