I once read of a "conception plan" which went like this (assuming you have a 28 day cycle; if your cycle is shorter or longer, you'd need to adapt the plan accordingly):
- Start having sex every other night from CD8.
- Start using an ovulation predictor kit on CD10.
- Once you get a positive on your OPK, have sex that night and every day of the subsequent two days.
Assuming that you ovulate on CD14, this could mean:
Sex on CD8, 10
positive OPK on CD12 and CD13
Sex on CD12, 13, 14, (15)
So you'd have had sex 5-6 times, and you'd have optimal chances for conception, and even if the OPK doesn't work (they don't always) or you had ovulated earlier or later than usually, you wouldn't have missed a chance.
Anyone who is finding it hard to find the energy to have sex 3 times a week for the whole month might find this plan interesting. Good luck!
btw recent research (published 2009, so many "specialists" might not know of it yet) has demonstrated that daily sex actually IMPROVES sperm quality; and large scale statistics clearly demonstrate that the chances to conceive rise with every time you have sex inside your fertile window. It's better to have sex two nights in a row if you know you are fertile, compared to "saving" the good sperm for the day of ovulation...
oh and another btw: doctors of all kinds USUALLY (there are exceptions of course) don't take women who chart their basal temps and observe their CM seriously. But that simply doesn't mean that it doesn't work. Yeah if you had sex every other night all month long, that might increase your chances, but hey, who's seriously going to do that for 6 months or so? Pragmatically speaking, ANYTHING which helps you know "when" is helpful. And once you have a clear and sustained temperature rise, you can take a break - once per week or so (to keep the sperm fit) will be more than enough!