The mucosa of the cervical canal (endocervix) is composed of a single layer of mucin-secreting columnar epithelium, which lines both the surface and the underlying glandular crypts. Isolated neuroendocrine epithelial cells of argentaffin type or argyrophil type are admixed with the normal endocervical cells.
Air travel Pregnant travellers can normally travel safely by air. In the absence of medical or obstetrical complications, pregnant women can safely fly up to 36 weeks gestation. Most airlines restrict travel in late pregnancy or may require a written confirmation from a physician.
If you have an uncomplicated pregnancy, you are likely to be able to travel during most of your pregnancy. Just be sure to discuss air travel and extended trips with your doctor ahead of time. When traveling, it's also smart to carry a written record of your due date and any medical conditions you have.