受精过程在微重力环境下能够正常完成，但是继续培养后研究人员发现，初期胚胎的生长 速 度 缓慢。经观察，受精卵分裂过程中，向胎盘一侧的细胞分化被抑制，这一侧聚集的细胞数量少于正常值，延缓了胚胎生长。雌鼠被植入经培养得到的胚胎后，虽然也能生产正常的幼鼠，但产子率只有正常情况下的一半。
From Wikipedia, the free encyclopedia
Sex in space refers to sexual activity in the weightlessness and/or extreme environments of outer space. Usually only human sexual activity is considered. The act of human intimacy, sexual intercourse, and procreation distinguished by the state of weightlessness (precluding artificial gravity) presents difficulties surrounding the performing of most sexual activities due to Newton's Third Law. The issue also includes conception and pregnancy in off-Earth environments.
The topic of sex in space has been hotly debated to clarify its potential impact on human beings in the isolated, confined, and hazardous space environment. Past discussions often included attempts to determine the veracity of speculations (e.g., about the STS-47 mission, on which married astronauts Mark C. Lee and Jan Davis flew), and even hoaxes, such as Document 12-571-3570. Experts such as Princeton astrophysics professor Dr. J. Richard Gott consider humanity's expansion into space crucial to survival, but it was considered taboo for decades of spacefaring exploration history.
As of 2009, with NASA planning long-term missions for lunar settlements with goals to explore and colonize space, the topic has taken its respected place in life sciences. Scientist Stephen Hawking publicly concurred in 2007 that possibly human survival itself will depend on successfully contending with the extreme environments of space.
Numerous physiological changes have been noted during spaceflight, many of which may affect sex and procreation, although it remains unclear whether such effects are due to gravity changes, radiation, noise, vibration, isolation, disrupted circadian rhythms, stress, or a combination of these factors.
The primary issue to be considered in off-Earth reproduction is the lack of gravitational acceleration. Life on Earth, and thus the reproductive and ontogenetic processes of all extant species and their ancestors, evolved under the constant influence of the Earth's 1G gravitational field. It is imperative to study how space environment affects critical phases of mammalian reproduction and development as well as events surrounding fertilization, embryogenesis, pregnancy, birth, postnatal maturation, and parental care. Gravity affects all aspects of vertebrate development, including cell structure and function, organ system development, and even behavior. As gravity regulates mammalian gene expression then there are significant implications for successful procreation in an extraterrestrial environment.
Studies conducted on reproduction of mammals in microgravity include experiments with rats. Although the fetus developed properly, the rats that developed in microgravity lacked the ability to right themselves. Another study examined mouse embryo fertilization in microgravity. Although both groups resulted in healthy mice, the authors noted that the growth rate was slower for the embryos fertilized in microgravity than for those in normal gravity.
The psychosocial implications of in-flight sex and reproduction are at least as problematic as the related physiological challenges. For the foreseeable future, space crews will be relatively small in number. If pairing off occurs within the crew, it can have ramifications on the crew's working relationships, and therefore, on mission success and crew operations. Behavioral health, close proximity, compatibility and coupling will all be factors determining selection of crews for long term and off-planet missions.
Lyubov Serova, a specialist with the Russian Institute for Biomedical Problems (IBMP) in the field of procreation in the conditions of spaceflight, says "After a period of adaptation for weightlessness, people will not need any special devices, like elastic belts or inflatable tubes to have sex in space," and "We study the impact of weightlessness on the reproductive function of male and female bodies by using mammals as test subjects, particularly rats." The overall conclusion is that sex in space is not a physical problem, and that individuals motivated enough to embark on space flight won't be distracted by sex.