The trigger shot given to you contains human chorionic gonadotropin (hCG) hormone that has an activity similar to the luteinizing hormone (LH) which is the hormone responsible for causing ovulation in the body. Ovulation prediction kits are based on the principle of detecting a rise in the LH levels thereby indicating that ovulation is about to occur. These kits do not indicate whether or not ovulation has actually occured. As you took the trigger shot, thereby ensuring the LH surge, you need not have used the ovulation prediction kits. The fact that it is faintly positive means that the LH surge has already occured and most probably you must have ovulated in the 42 hours as your doctor suggested.
A better way of documenting ovulation is to check serum progesterone levels 7 days after presumed date of ovulation or to chart the basal body temperature. In the basal body temperature method, you need to use a BBT thermometer to chart your temperature daily. Around ovulation, you will see a dip and then a rise in the temperature that stays high throughout the later half of the cycle.
Wish you all the very best with your fertility issues. Hope you complete your family soon.
These Q&A’s are for educational purposes and should not be relied upon as a substitute for medical advice you may receive from your physician. If you have a medical emergency, please call 911. These answers do not constitute or initiate a patient/doctor relationship.