if u have irregular menstruation, calculation will be based on ur ovulation date. Good you know ur ovulation date. so, the calculation will be (today's date - 31 Oct) + 2 weeks. I also calculated my preg weeks based on my ovulation date as I hv PCOS. During my first scan at 8weeks, my calculation turned out to be accurate. Take care sis.
set up an appt with gynae and do an ultrasound scan. they will measure the CRL of the embryo in the sac to determine the EDD. cos your ovulation period could take longer than you expected so it may not be accurate. and edd is calculated by the first day of your last menses not by your ovulation date.
LMP may not be accurate. The most accurate is to do an ultrasound with your gynae. He or she will advise on the actual gestational age and EDD.
EDD is calculated from your last period not on your ovulation but again LMP is also not accurate. Ultrasound is more correct.
calculated from the first day of your last menstrual period