Fimbriae (common pili) and flagella on the surface of bacterial cells. Left: dividing Shigella enclosed in fimbriae. The structures are probably involved in the bacterium's ability to adhere to the intestinal surface. Right: dividing pair of Salmonella displaying both its peritrichous flagella and its fimbriae.
Relaxin's peak is reached during the 14 weeks of the first trimester and at delivery. It is known to mediate the hemodynamic changes that occur during pregnancy, such as increased cardiac output, increased renal blood flow, and increased arterial compliance.
Avoid Overstretching. During pregnancy, the hormone relaxin increases flexibility (the name itself is a bit of a giveaway!) and helps to prepare the body for birth. Because this influx of relaxin causes the ligaments to become more lax, pregnant students should take extra care not to overstretch.