The only way to ovulate prior to a positive OPK is to have missed your OPK surge. This is common -- especially for those who ovulate very quickly following the LH surge. But evidence suggests that eggs are more likely to 'pop out' closer to 36 hours following a surge (day and a half). Hence, FF tends to put the ovulation one day after your positive OPK.
After an egg comes out, the follicle undergoes a change to create the corpus luteum, which then starts to produce progesterone. Progesterone production is still linked to the pulsing of your LH, so if your LH pulses slower, so will your progesterone. It's more sensitive to the pulsing than to the actual levels of LH.
Implantation relies on a series of very fortunate events all of which need to be impeccably timed by the body. Some evidence shows that the fallopian tube actually prepares the egg for fertilization as it travels and drops the egg off in the uterus where it might sit for 3-4 days preparing for implantation in a beautifully lined uterus, thanks to the progesterone and the estrogen.
It's a wilderness, though, because your body can scavenge the egg, your fallopian tube can slow it down or speed it up (aka drop it off in the uterus too early or too late, when the pH can render it useless), and your lining may not be prepped fast enough or with the right enzymes.
Having enough progesterone (there is a critical level) for longer means that you have a bigger window for implantation. Some women have a very small window and therefore are subfertile.
Hope this helps!
1940s /50s retro!
Beautiful!
in a cycle while using it, don't stop using it until you talk to a doctor about it, just to be safe.
