Speed ratings on tires are expressed in letters and are generally listed along with the load index for a tire after the size, for instance 245/40R18 93H. 93 is a load index and the H is the speed rating .â¦. What Does Z Mean On The Tires | Zr Speed Rated | Zr Rating. 1  Differences in Tire Speed Ratings Explained.
Effacement: Thinning of the cervix. In the last month of pregnancy the cervix will begin to stretch and thin. This is an indication that the lower portion of the uterus is getting prepared for delivery, as a thinner cervix dilates more easily. Your health care provider can check for effacement in the final two months of pregnancy.
1 The cervix is actually a part of the uterus, but made up of different tissue. 2  During pregnancy, the cervix is thick and closed. 3  As you approach the time of birth, your contractions draw the cervix up into the body of the uterus, and it becomes thinner (called effacement) and opens (called dilation). The cervix is actually a part of the uterus, but made up of different tissue. 2  During pregnancy, the cervix is thick and closed. 3  As you approach the time of birth, your contractions draw the cervix up into the body of the uterus, and it becomes thinner (called effacement) and opens (called dilation).