LOA is the English abbreviation for Left Occipital Anterior, which indicates the baby’s fetal position: L means left, O means occipital, A means anterior, and together, LOA means that the baby’s occipital bone is located in the left anterior part of the mother’s pelvis. If you feel from the abdomen, the back of the baby in LOA is located in the left front of the mother’s abdomen, with the head facing downward and the baby’s face facing the mother’s spine, which is equivalent to the baby lying on its back. LOA is a better birth orientation, other fetal orientation are ROA right occipital anterior, LOP left occipital posterior, ROP right occipital posterior, LOT left occipital transverse, ROT right occipital transverse and so on. LOA does not mean that the baby is in labor. The measure of whether the baby is in labor is described as S. S indicates the sciatic spine of the pelvis, which is in the middle of the mother’s pelvis. They are two small bony protrusions. If the lowest point of the bony part of the baby’s head reaches the level of the sciatic spines, the baby is in labor, which is indicated by S0. If it is 2 cm above the sciatic spine, it means that it has not yet entered the pelvis, indicated by S-2. If the lowest point is 2 cm below the sciatic spine, the uterine opening will not reach this level until after labor is in progress, which is indicated by S+2. If you are a primigravida, you will usually enter labor around 38-39 weeks of pregnancy. In the case of a primigravida, it is usually around 38-39 weeks. In the case of a primigravida, it is much later, and the head of the fetus may enter the uterus only after the contractions have dilated the uterus.