Rat pregnancy and parturition survive spaceflight challenge: new considerations of developmental consequences

Results of the NASA-NIH.R1 and NASA-NIH.R2 pregnant rat studies are reported and compared with results of Cosmos-1514 study. Similarities and differences between the Cosmos and STS flights are reviewed. STS rats were videotaped so that in-flight and post-flight behavior could be observed. Rats were observed during readaptation to 1-g and labor and delivery. Results indicate that pregnancy can proceed after exposure to microgravity and that vaginal delivery can occur despite readaptation to 1-g. Analysis of videotape revealed that flight dams experienced almost twice as many labor contractions as controls.