What is Testosterone?
Testosterone is a hormone generally associated with the differentiation between men and women. Testosterone levels are higher in men than women. The total testosterone blood test may be ordered in men who are aging and showing signs of reduced testosterone levels, including fatigue and loss of muscle mass. Women may also be tested for testosterone levels if polycystic ovarian syndrome is suspected.

Irregular testosterone levels can cause infertility in both men and women. Men may have trouble achieving and maintaining an erection or reduced fertility if testosterone levels are irregular. Women may also suffer infertility, loss of menstruation or development of male characteristics like facial hair growth.

Testosterone levels increase throughout pregnancy, but return to normal after birth.

Normal Value Range

  • Negative Pregnancy Adult: 6 to 86 ng/dL or 0.21 to 2.98 mmol/L
  • Pregnancy Trimester One: 26 to 211 mg/dL or 0.9 to 7.32 mmol/L
  • Pregnancy Trimester Two: 34 to 243 mg/dL or 1.2 to 8.4 mmol/L
  • Pregnancy Trimester Three: 63 to 309 mg/dL or 2.2 to 10.7 mmol/L

< Laboratory Values During Pregnancy