This will enable you to estimate the stage of pregnancy she has reached, and check the accuracy of the due date calculated from the mother’s last normal menstrual period.Then we discuss possible reasons for the uterus growing too quickly or too slowly, and what actions you should take if you suspect that something may be wrong.Sometimes a woman misses her menstruation for another reason, and then gets pregnant later.This woman could really be less pregnant than you thought, so the uterus is smaller than you expect.If the top of the uterus is above the bellybutton, measure how many fingers above the bellybutton it is.When you measure fundal height at every antenatal visit, write down the number of fingers you used to measure the height of the uterus on the woman’s antenatal record card.At about eight to nine months (36-40 weeks), the top of the uterus is almost up to the bottom of the mother’s ribs.
For example, it assumes that the distance between the pubic symphysis and the umbilicus is 20 cm at 20 weeks’ gestation, but it can be as long as 30 cm and as short as 14 cm.
They start counting at the first day of the last normal menstrual period (LNMP), even though the woman probably got pregnant two weeks later.
Counting this way makes most pregnancies 40 weeks long (or you can say a normal gestation is 40 weeks).
The uterus should grow about 1 cm every week, or 4 cm every month.
Doctors, nurses and many midwives are taught to count pregnancy by weeks instead of months.