Which of the following are true regarding estimation/ calculation of gestational age?
A. A woman’s ‘gestation’ is 2 more weeks than the time period since conception.
B. If a cycle is >28 days, the EDD will be later and needs to be adjusted.
C. If the cycle is <28 days the number of days by which the cycle is less than 28 should be deducted from the EDD.
D. Measurement of crown–rump length between 7 and 14 weeks: if there is >1 week difference between LMP and scan, EDD estimated by LMP is used.
E. Biparietal diameter or femur length are best used to date between 14 and 20 weeks if there is no early scan and the LMP is unknown.
F. None of the above.