Hodge planes are levels used to imaginatively divide the pelvis from the upper to the lower straits in order to locate the position of the fetal presentation during birth, as it passes through the birth canal.
In total there are four planes numbered from top to bottom, the first plane being the highest and the fourth the lowest. Needless to say, at the time of delivery, the vertical position and pelvic rocking aids this pelvic descent.
The four planes of Hodge
- Hodge’s close-up (I) is the highest of the four, extending with an imaginary line running from the upper end of the pubic symphysis in front to the promontory of the sacrum behind. When the salient pole of the fetus reaches this plane, it is said to be still mobile.
- The second Hodge plane (II) is an imaginary straight line parallel to the previous one and passes, in front, from the lower border of the pubic symphysis to the second or third vertebra of the sacrum. When the salient pole of the fetus reaches this plane, it is said to be a fixed presentation.
- The third plane of Hodge (III) , equally parallel to the first two planes, is a straight line which, at the height of the ischial spines, intersects the ischium and the fourth sacral vertebra. When the fetal presentation reaches this plane it is said to be embedded. The most prominent part of the fetus protrudes from the vulva only between contractions.
- Hodge’s fourth plane (IV) : line that starts behind the vertex of the sacrum and runs parallel to all the previous ones. It is said to be deeply embedded. The most prominent part of the fetus protrudes from the vulva even between contractions, and is the prepartum step.
In Babies and more | When to go to the hospital if you are in labor ?, Dilation of labor in water: the help of bathtubs to give birth
