In average, the LH peak occurred <...> 1.2 days after US-DO.
page 281.
US-DO
The ultrasound-determined day of ovulation
page 280.
In 17 cycles (6%), the LH surge ended before the US-DO but, in the overwhelming majority of the cycles (94%), the LH surge continued after US-DO; in 60% of the cycles, it lasted >3 days after US-DO.
page 281.