I am a mother of a healthy 2yo, but have not conceived second child despite 2 years of unprotected sex w/ extremely irregular cycles... is this normal?

Pregnancy: Often women after having their first child can develop " secondary infertility". You need to go toy your GYN and have them examine you and test your blood. Most likely you are just exhausted from running around with a two year old bit please get checked by your doctor.

Time for workup: If you haven't already, it is time to talk with your OB & begin the process of assessing your reproductive health. S/he may refer you to a fertility center & hubby needs to come along because he can be part of the problem too.