To determine the acceptable timeframe for placental collection, Wolfe et al. collected multiple samples from first and third trimester placentas at serial time points 0-120 minutes after delivery, simultaneously comparing the traditional snap-freeze technique to commercial solutions designed to preserve RNA (RNAlater™, Ambion) and DNA (DNAgard®, Biomatrica). First trimester (10-12 weeks) and third trimester (38-40 weeks) placental samples were collected from women undergoing abortion procedures and women undergoing scheduled term cesarean sections, respectively. Samples approximately 1 cm³ in size were obtained from the placental disc, halfway between the umbilical cord insertion point and the placental margin. Care was taken to exclude large blood vessels. Note: Only samples collected at 0 minutes in RNAlater™ were used for this analysis

Tissue Condition Samples
Test placenta third trimester pregnancy 9
Control placenta first trimester pregnancy 9
Gene Fold Change (log2) Significance Genus Species