During ultrasound on your sonogram, it will state the exact number of weeks of your pregnancy. LMP is just rough estimation of your EDD hence it may not be accurate.
Follow the sonogram then. Because you have irregular menses it might be miscount on your end. Thats why it is best to put your period day, sexual intercourse day, ovulation days on calendar or apps to specifically count the days. Though, this can be wrong sometimes but if we are bless to be pregnant then we have to accept it. Just like my second pregnancy 🤣🤭 Unexpected but my LMP, ovulation and sexual days fall within the days when I checked on my apps. Nevertheless I accept it and the gap is just nice of 4 years.
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