Types of Birth Control Pills
Birth control pills are categorized as combination or continuous. Combination birth control pills contain estrogen (typically in the synthetic version of ethinyl estradiol) and progestin. Continuous birth control pills, also called the mini pill, contain only progestin. Progestin is a man-made hormone that has similar properties to natural progesterone. There are eight kinds of progestin and each type is classified differently, often by generation and its effects on a woman's body. There are no estrogen-only oral contraceptives so every birth control pill you take will have a type of progestin.
The Effects on a Woman's Body
The effects of progestin on a woman's body are usually described in terms of estrogenic, progestational and androgenic effects.
Progestational activity refers to how the progestin stimulates the progesterone receptors ultimately lessening menstrual bleeding and preventing ovulation. Estrogenic activity is used to describe how the amount of synthetic estrogen in the birth control pill counters androgen-related activity or side effects. Generally a higher amount of estrogen means a lower amount of androgenic activity. Androgenic effects are basically the unpleasant side effects like unwanted hair growth (hirsutism), more acne breakouts and a modest slow of the body's carbohydrate metabolism. Each generation of progestins is better and causes less androgenic activity.
This is a first generation progestin. This means it has low progestational and estrogenic activity and also tends to be less androgenic than second generation progestins. It's usually used in low dose combination pills, meaning that the pill has less than 50 mcg of synthetic estrogen, ethinyl estradiol. Norethindrone tends to improve lipid profiles by lowering LDL (bad) cholesterol and raising HDL (good) cholesterol.
This first generation progestin is categorized as have medium progestational activity. They tend to have little androgenic activity and few estrogenic effects. They also tend to cause mid-cycle breakthrough bleeding, but this symptom is combated with higher combining this progestin with higher amounts of estrogen.
This type of progestin has slight estrogenic effects and low progestational activity and is a first generation progestin. It tends to have lower androgenic activity which can be helpful for women who suffer from negative pill side effects like fluid retention, nausea or migraines. One example of an oral contraceptive brand that uses norethindrone acetate is Estrostep which increases estrogen levels with a constant progestin does to copy the way a woman's natural menstrual cycle works.
This second generation progestin has high progestational and androgenic activity. It can also increase the bad cholesterol and lower good cholesterol.
This third generation progestin has been proven successful in treating acne. Ortho Tri-Cyclen Lo is an example of a brand name that uses this type of progestin with mid-level doses of estrogen. It's FDA approved for the treatment of acne, doesn't often cause spotting and lowers the chances of experiencing vomiting and nausea.
Levonorgestrel is the most widely prescribed progestin worldwide. It's second generation and has both high progestational and androgenic effects. Basically, it's highly effective but can produce a startlingly high amount of negative side effects in some women. This type of progestin has also be FDA approved for emergency contraception when used in higher doses. Low-dose estrogen brands are also available for daily oral use. Lybrel, Seasonique and Seasonale are three mini pill versions with this type of progestin that have been FDA-approved.
This type of progestin is third generation and tends to have less of a negative impact on metabolism and weight gain as well as acne. It doesn't cause you to gain weight and it won't cause you to break out. It tends to slightly raise good cholesterol as well. It can be helpful for women with dysmenorrhea and migraines. The biggest downside of desogestrel is that this progestin can slightly raise the risk of non-fatal venous thrombosis (blood clot in the leg). Cyclessa is a brand name containing this type of progestin.
Birth control pills with this type of progestin tend to alleviate symptoms of PMS including water retention, negative mood and increased appetite. It's especially effective at treating bloating and water retention because it suppresses the secretion of water-holding hormones and electrolytes. YAZ is an example of a birth control brand name that contains drospirenone.