You probably know from grade school health classes that testosterone is important for boys and estrogen is important for girls but, well, it's a bit more complicated than that. (Isn't it always?) Women naturally produce testosterone as well (and men, estrogen), but there could be warning signs a woman isn't producing enough testosterone on her own. While it's true that women produce less of the hormone testosterone than men, according to Harvard Women's Health Watch, women need testosterone to make a specific form of estrogen called estradiol. Testosterone is important in women's bodies, so not making enough naturally, either due to a condition of some sort or the aging process, can be problematic.
High levels of testosterone in women are characteristic of polycystic ovarian syndrome (PCOS) and can potentially lead to infertility. Testosterone levels decline as you move towards menopause, but there can also be some signs that you may not be producing enough. Keep an eye out for these signs to determine what, if anything, needs to be discussed with a doctor or done to remedy the situation.