Calculating Pregnancy Due Date ... cont.
c) Use of Tape Measure: Measure from Notch of symphysis pubis over fundus without tipping
the corpus back. The figure be multiplied by 8 and divided by 7 to get the number of weeks To increase reliability: Same person must examine the client at each visit and establish a protocol for use e.g. Position of client on couch, device used – tape or finger breadths, method used – contour of fundus, tape elevated, between index and middle finger, palm of hand at fundus.
d) McDonald’s Rule (not commonly used in Malawi)
• FH (cm) x 2/7 = duration of pregnancy in lunar months
• FH (cm) + 3.5 = duration of pregnancy in months
• FH (cm) x 8/7 = duration of pregnancy in weeks
e) Ultrasonography: Very accurate but expensive and not available in all the centres. Tends to be used in special cases but is becoming increasingly popular
• If unable to establish LNMP
• Fundus large than dates

Very Accurate
The importance of using the formulas is that the couple can be guided in:
a) Preparation of the baby’s arrival.
b) Not surprised by certain features of gestation.
c) Able to follow milestones of pregnancy.

Enrichment Resource: Health-cares.net