It's always recommended to stoping any exogenous testosterone, get your natural hormones in range, healthy HPTA and such.
There is often inherent conflict in the overlapping fields of male fertility and andrology. While the goal of all male fertility specialists is to facilitate and preserve biologic paternity, many practitioners also care for a significant number of patients ...
www.ncbi.nlm.nih.gov
"If a planned pregnancy is desired within the 6 to 12 months time frame, the authors suggest continuing TTh with adjuvant 500 IU HCG every other day [
18]. CC at a dose of 25 mg per day should be considered an optional addition throughout this time. When planning for pregnancy over a year away, TTh with adjuvant 500 IU HCG may be continued but patients should be cycled off every six months given the increased risk of impaired fertility with prolonged, uninterrupted TTh [
25]. Each off-cycle involves a four-week cycle of 3,000 IU of HCG every other day and CC 25 mg daily. During any of these above regimens, anastrozole may be added and titrated in dose to address any elevations in estradiol. Patients who cannot tolerate CC should substitute tamoxifen 10 mg twice daily.
Many men receiving TTh may not be interested in fertility but still wish to maintain normal testicular size. It is recommended that these individuals take 1,500 IU HCG weekly while on TTh. This dose is thought to be enough to maintain adequate levels of intratesticular testosterone in order to minimize testicular volume loss. Some men feel that periodically cycling off of TTh is symptomatically beneficial but this is an anecdotal observation and primarily a matter of patient preference."
Do let me know if there's new update on the protocols since i'm too lazy right now to search most recent studies