Hello! I am new to this side of the board but have been ttc my no2 for 2yrs now. I am nursing my first child though so, as you may know, nursing is said to lower progesterone (hormone needed for pregnancy) by raising prolactin. Therefore I feel I may be able to give you advise despite nursing not being the issue for you.
My daughter is only on three nursings at night now and as many nursing mothers can still get pregs I feel my 'issues' are more about me and my hormones being out of whack than from the nursing itself and that has led me to search for a 'cure'.
Firstly its possible your hormones just got messed and never righted after the birth of your first. Apparently low progesterone is a common secondary infertility issue.
Do you chart your temps or anything? I first discovered I had low progesterone by my luteal phase being short - an average 7 or 8 days between ovulation and AF. This is too short and a good place to start with checking if your functioning correctly.
As prolactin lowers progesterone you may also have some of these low progesterone symptoms:
Infertility
Thyroid dysfunction
Depression
Fibrocystic breasts
Weight gain
Gallbladder disease
Low Blood Sugar
Panic attacks
Water retention
Irregular menstrual cycle
Blood clots during menstruation
Magnesium deficiency
Vaginal dryness
Breast tenderness
Low sex drive
Insomnia
Remedies can be Vitex (aka Agnus Castus). This can restore balance and indirectly heighten progesterone although I tried (and am still taking) 400mg from Dec and saw no difference except reduced PMS symptoms. Then I tried 200mg of B6 from March and this DID correct my luteal phase defect (to 10 days and 11 days) but my last cycle was back to 7. I still think it works and as I have nursing on top both these things could work better for you. But most excitingly I have just researched and ordered
Progesterone cream. You apply it from ov to AF and I am hoping it will make all the difference with ttc. Its actually the reason I came here to ask others but I saw your post and just had to answer first!
As I haven't used it yet (waiting for ovulation) I can't say 'hey it works, its great' or anything but it could be just what you need to battle high prolactin! Look it up online - its used for lots of things, not just fertility, but I have read really good stuff about it helping women concieve!