"Second question: What's up with a positive OPK not followed by a spike? She always gets a positive and then a spike 4-5 days later. Which day is she ovulating? We always just assume the day after the positive OPK and figure she has a delayed rise. If we were straight, we'd just keep trying until the spike, but we don't have that luxury, and obviously we don't want to miss it. What gives?"
EasttoWest: does her temp slowly rise up for those three to four days before she spikes? Or does it tend to go a little up and down over the next 3-4 days? It could be that her body gears up, doesn't ovulate and then her body tries once more. In this case, she could be releasing enough LH to get a positive on the OPK but it's not actually releasing until later. Do you continue the OPKs even those four days? And if so, how long does the positive OPK last? I don't know what other methods you are using to pinpoint ovulation but this is why a third and/or fourth sign monitoring is important (cervical mucous, cervical position, etc). It's when three of those signs line up that she is likely to ovulate. Is her CM more egg white two days after a positive OPK or at that fourth or fifth day after the positive OPK?
You mention the luteal phase is "between 11-13 days." Usually, ones luteal phase does not change. Maybe one day here or there, but typically it's exactly the same each month. What can change is ovulation. Things like stress can change when someone ovulates, as well as fertility drugs. So what's probably happening is you guys are having a hard time pinpointing her ovulation which is giving you only a rough estimate of the luteal phase. Once you get that more secured, you'll know her luteal phase and it may turn out to be short. 11 days is a little on the short side but it's still considered "normal." Mine is 11 days but I've taken Prometrium over the years "just because" of that shortened luteal phase. Anything less than 10 days is considered medically to be a Luteal Phase Defect.