Tricep fat is a sure sign of low testosterone in females, with contraception playing its part in lowing the product of female testosterone.
Let explain menstrual cycle briefly. The menstrual cycle begins on the first day of menses (the period) and continues for about 28 days on average. During that time a series of events happens within the body to prepare the uterus for conception. Ovulation, when a female’s ovaries release an egg to possibly be fertilized, occurs typically around day 14 of the cycle. At this time the sex hormones estradiol and testosterone peak. Testosterone causes sex drive, energy levels, mental sharpness, and mood to all increase. To put it simply, it makes you want to get jiggy with it and makes you attractive to your partners. After ovulation occurs, progesterone, another sex hormone, rises. If conception occurs, progesterone stays high. If not, progesterone abruptly falls, causing the lining of the uterus to shed and menses to start.
So how does contraception cause low testosterone levels...?
Remember that whole bit about ovulation and testosterone? If we’re suppressing ovulation with contraception, guess what doesn’t happen? The body doesn’t get that bump in testosterone and for those of you with athletic and body composition concerns, this presents a problem.
Without testosterone, or without adequate amounts, it’s hard to build strength, muscle mass, and very hard to maintain a favorable body composition. Not impossible; just much harder. Also, when you don’t get that testosterone boost, your mood and libido is negatively affected. So, I guess you could say that birth control also helps to prevent pregnancy by making the patient totally uninterested in having sex. Taking birth control pills also has the side effect of causing something called sex hormone binding globulin (SHBG) to increase. The liver produces this in response to the ingestion of oral estrogen and has a high binding affinity for testosterone. So, not only are the ovaries not making as much testosterone because of the suppression of ovulation, but what little is circulating is likely to be bound up by SHBG that has gone wild because of the ingestion of the birth control pill.