I just came across this very interesting consumer rating of pregnancy and ovulation tests. There are some very interesting results. Especially regarding ovulation predictor kits. It seems around 10% of women will never have LH surges strong enough to be detected on some kits. Explains why I have only seen 1 positive result in more than 6 months of using them.
http://www.cbsnews.com/stories/2003/01/ ... 8075.shtml
http://www.cbsnews.com/stories/2003/01/ ... 8075.shtml