Why LOA Is Easier Than ROA
It is commonly known that LOA is the position preferred by babies when they have a choice. What is special about the left side?
By the 38th week of pregnancy, there is more space on the left side of mother’s abdomen for baby’s long back. Why? Well, about now, the uterus develops a lean to the right at the top, and a twist to the left at the bottom (google uterine right obliquity and dextro- rotation ) The reason is probably that there are more abdominal contents on the left side pushing the uterus sideways. Think of the curve of a banana—the inside curve is shorter, and so less comfortable for baby.
During a second or later pregnancy, the uterine lower segment is softer and rounder, so some babies do choose to lie as ROA, though there is less space on that side.
As long as his/her back stays toward mother’s front, labour will proceed steadily as with LOA.
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