Pattern. 1  the pattern will be compared to the name. * 2  is a wildcard that will match zero or more letters example: *oo* will match names which contain oo. _ 3  is a wildcard that will match exactly one letter example: __z will match names which have two letters and then a z.
Normally, the placenta is attached to the uterus above the cervix. In rare cases, the placenta forms low in the uterus and is partially or completely covering the cervix. When the placenta is blocking the cervix, it is called placenta previa. Placents posterior mean high risk in doctor's language Posterior means back.
A partial previa occurs when the placenta asymmetrically covers only part of the internal cervical os. A marginal previa occurs when only an edge of the placenta reaches the internal os. A low-lying placenta occurs when the placenta implants in the lower uterine segment but does not reach the internal os.