Math is hard
The longest wait in an IVF cycle is not the two weeks between embryo transfer and pregnancy test. And it's not the two weeks between a positive pregnancy test and the first ultrasound. No, the longest wait is between a negative pregnancy test and a post-cycle consultation.
I bet they've done extensive research on how long it takes a woman to stop being dangerous after a failed cycle. I bet there's a sophisticated algorithm they apply in every case.
"Let's see. This one's for Julie? Okay, we might need extra paper. Now, she's 32. Her estradiol level at trigger times her IQ divided by the number of disappointments she's suffered at our hands...multiplied by the square root of how much she paid us this time out...(scribbling sounds)...hmm, carry the 8...round up here...number of injections, cubed...average temperature of the ultrasound wand...(head-scratching noises)...check my math here, Bert...yes. Hmm. Interesting.
"Nurse? Nurse! Cancel all the appointments, close the office, lock the doors, and put on your riot gear. This one won't be safe for another month at least."