A standard language variety is a variety that's recognized as more correct* and acceptable than other varieties. Standard varieties have the following prototypical properties, though not all of these properties will be shown by all standard varieties, and non-standard varieties may nevertheless have some of them:
All airlines make up their own rules and regulations regarding pregnant women. Some do not restrict travel at all, no matter what stage of pregnancy a women is in, and others start to restrict at 7 months, although the majority restrict around 36 weeks.
Most experts say it is unlikely that flying will cause pre-term delivery. I don't think that there is any evidence to suggest that flying can cause women to go into labor, says Dr. John Repke, chairman of the department of obstetrics and gynecology at the University of Nebraska Medical Center in Omaha.