Fertility blood tests

Infertility on TRT: What to Monitor

Testosterone replacement therapy (TRT) often lowers sperm production, because testosterone from outside the body tells the pituitary gland to cut back on LH and FSH, the two signals the testicles need to make sperm. The measurements used to follow this are a semen analysis, which is the direct measure, plus blood levels of LH, FSH, testosterone, estradiol and prolactin.

What is a semen analysis?

A semen analysis measures the volume of a semen sample and the number, movement and shape of the sperm in it. It is the main lab test for male fertility, and it is not a blood test: the sample is collected at a clinic or lab, or at home and delivered within 30 to 60 minutes. Blood-test ordering services don’t sell it, but they do sell the hormone tests often ordered alongside it.

What blood tests do bodybuilders track?

The blood tests most often discussed in bodybuilding and strength communities fall into four groups: hormones (total and free testosterone, estradiol, SHBG, LH and FSH), general health panels (CBC and CMP), heart and metabolic markers (lipid panel, ApoB, A1c, fasting insulin), and thyroid, iron and vitamin markers. Hard training changes some of these numbers by itself, which matters when comparing results over time.