I wanted to add a brief postscript to the entry below...
For those of you who don't know fertility signs, your "luteal phase" is the second half of your cycle - the post-ovulatory half - and it is generally constant for any given woman. For example, even if your cycle varies all over the place (28 days, then 32 days, then 34 days), your luteal phase will stay the same (for example, 11 days plus or minus one day).
Doctors vary on what they consider to be "normal" for a luteal phase. Some consider anything under 12 to be dysfunctional; some consider anything under 10 to be dysfunctional. (When estimating a due date, they will use a default value of 14 days. This is one reason why it is SO important to chart your fertility signs - otherwise your "estimated due date" may be horrendously off. With my cycles, which are long with short luteal phases, my due date will usually be one week later than that estimated by a pregnancy wheel. Thus, if I didn't know my fertility signs, I could conceivably have had an OB pressuring me to induce when my baby was still premature.)
Anyhow, regarding my last post, when I wrote that I thought that I was pregnant because I had a long luteal phase (12 days as opposed to 10): I had started taking vitamin B6 supplements a month or so ago to deal preemptively with morning sickness. BUT, vitamin B6 also happens to be one of the over-the-counter remedies for short luteal phases, LOL!!! I had known that but forgotten about it, as I was not at that time wanting to increase my fertility. But I can now testify that it works!!! I'll post next month to see if my luteal phase continues to lengthen with additional B6 supplementation. Kind of cool to see that such a simple supplement can do such amazing things!