Bartholomew's Rule of Fourths Calculator




Fundus







Enter the Position of the Fundus:








Bartholomew's rule of fourths calculator calculates the estimated age of gestation (aog) of a fetus depending on the the height of the fundus.

Bartholomew's rule of fourths does not use a numerical height value to compute gestational age, but landmarks.

If the fundus is at the symphysis pubis, then the age of gestation is about 12 weeks.

If the fundus is midway between the symphysis pubis and the umbilicus, the age of gestation is about 16 weeks.

If the fundus is at the umbilicus, the age of gestation is about 20 weeks.

If the fundus is at the xiphoid process, the age of gestation is about 36 weeks.

Know that the bartholomew's method of calculating gestational age is an approximation. It does not and cannot accurately predict gestational age, but gives a close-enough rough estimate.

The fundus of the uterus, as shown above in the image, is the top portion of the uterus. As pregnancy progresses, the fundus expands to accomodate the growing fetus. The fetus grows inside of the uterus during pregnancy. As the fetus grows, so must the uterus. At 12 weeks, the fundus is at the symphysis pubis, which is about at the level of the top of the legs. At 20 weeks, the fundus reaches the umbilicus, which is at the level of the belly button. At 36 weeks, the fundus is at the xiphoid process, which is at the lower end of the sternum, which is the chest term. At this point, the mother is near term and delivery is close.

The reason this calculator is included is because many aspects of pregnancy and health and healthcare in general uses many electronic tools and components as predictors or markers for health. Many electronic tools are used in pregnancy, so this calculator can serve as a guide in the design of an electronic tool to predict pregnancy Being that health and electronics are being more interwined as ever before, all calculators predicting or forecasting healht can be used in the design of electronics for health.

Related Resources

Naegele's Rule Calculator

GPA System Obstetric History Calculator

TPAL System Obstetric History Calculator

GTPAL System Obstetric History Calculator

Autosomal Recessive Inheritance Calculator

Autosomal Dominant Inheritance Calculator