Hormones are important chemical messengers found in the body. In the female reproductive system, they regulate everything from libido to the menstrual cycle. Synthetic hormones can be administered to females with natural hormonal imbalances, and are used primarily as a form of fertility control.1
Hormones in the Human Body
Estrogen is a hormone naturally produced in a female’s ovaries, as well as by the adrenal glands. It plays an integral role in the development of the female body and in the female reproductive system. Estrogen induces the development of secondary sexual characteristics in females such as breasts, pubic hair, and armpit hair. It also functions to regulate the menstrual cycle. As a part of the reproductive system, estrogen serves to thicken the endometrial lining of the uterus in order to prepare for the potential implantation of an egg. Another important hormone, progesterone, which is produced by the corpus luteum in the ovary, assists in this process. If a fertilized egg is not implanted, there is a decline in the amount of progesterone produced, the endometrial lining sheds, and a new menstrual cycle begins. On the other hand, if the fertilized egg does implant, progesterone aids the progression of the pregnancy.2
When females have hormonal imbalances, they may experience side effects. For example, females with low progesterone production may experience irregular menstrual cycles, spotting and pain when pregnant, and frequent miscarriages. Females with low levels of estrogen experience infrequent menstruation, hot flashes, lack of vaginal lubrication, mood swings, and decreased libido. In contrast, high estrogen in females can cause weight gain, fibroids, menstrual problems, and depression or anxiety, amongst other side effects. Birth control and hormone therapies provide synthetic estrogen and progesterone replacement to help balance changes in natural hormones. If you believe you are experiencing any of these side effects, see a doctor.1
Hormonal Contraceptives Overview
There are two types of hormonal contraceptive methods: the first, the “combo” method, consists of a combination of estrogen and progestin. The other method only contains progestin (a synthetic hormone similar to progesterone). Both forms prevent the ovaries from releasing an egg during ovulation and thicken the cervical mucus to block the sperm from entering the uterus and fertilizing the egg.3
Estrogen-Progestin Combination Contraceptive Methods
Combination birth control methods include combination pills, vaginal rings, and birth control patches. Combination methods have varying amounts of hormones. Although contraceptives with both low and high estrogen levels provide the same amount of protection from pregnancy, they each carry different drawbacks and benefits that should be considered. Contraceptives with higher levels of estrogen are usually associated with an increase in health risks, while contraceptives with lower levels of estrogen do not regulate the menstrual cycle as effieciently. Talk to a healthcare provider for a complete list of estrogen-progestin contraceptive options.4
Among the female population using any of the progestin-estrogen combination birth control methods, studies have shown that with typical use (for example, forgetting to take a pill now and then), 92% are protected from pregnancy. With perfect use, however, 99.97% of females using combination birth control methods are protected.5
Estrogen-progestin combination methods may benefit females who have or have had the following:
- Irregular or heavy menstrual periods
- Ovarian cysts
- Iron-deficiency anemia
- Hot flashes
- A family history of ovarian cancer or endometrial cancer (combination pills are associated with an 80% reduction in the risk for ovarian and endometrial cancer when used for 10 years)
Consult with a doctor if you have had any of the above and are interested in starting birth control.
Side effects of combination birth control methods may include light or skipped menstrual periods, spotting between periods, nausea and vomiting, headaches, weight gain, tender breasts, depression or changes in mood, and changes in sexual desire. Many of these side effects may reduce or disappear following the first few months of use. Talk to a healthcare provider about switching to a different method or dosage of contraception if symptoms continue.
Females using estrogen-containing birth control are at a three to six times increased risk of developing blood clots, so report to a doctor immediately if you experience any of the following ACHES:
- Abdominal pain
- Chest pain
- Eye problems including a blur or change in vision
- Severe leg pain or swelling
Combination contraceptive methods should NOT be used by females who have a family history of blood clots, breast cancer, high blood pressure, liver disease, or diabetes, and who are breastfeeding for the first 6 months following childbirth. Women over the age of thirty-five and smokers have increased risks of potential side effects.1, 2
Progestin-Only Contraceptive methods
The progestin-only mini-pills are just as effective as the combination hormone pills when taken perfectly; however, they must be taken at the same time each day since the effects only last for twenty-four hours. There is also no hormone-free period of time, unlike many types of combination pills. The implant, a thin rod inserted under the skin, is over 99% effective for four years, at which point it needs to be replaced. The birth control shot must be administered every three months by a medical practitioner, and is 94% effective if used typically.4
Progestin-only methods may benefit females who are the following:
- Breast-feeding, since the low-dosage has no effect on the milk supply
- Aged over thirty-five
- Experiencing high blood pressure
- Aware of a history of blood clots
If you are worried about any of the above conditions, consult a doctor to discuss progestin-only contraceptive methods.
Side effects for progestin-only methods are generally less prevalent than those caused by combination methods, so progestin-only can be a good alternative for females experiencing any adverse effects from other types of contraception. However, females may still experience weight gain. Additionally, menstrual period irregularity is common with progestin-only methods.1
Hormonal birth control methods are a great way to prevent unwanted pregnancies and mitigate the effects of natural hormonal imbalances. There are many birth control methods, and each one has unique benefits and drawbacks. If you are interested in getting started on hormonal contraceptives, see a doctor and discuss which method will be the best one for you!
1. "What Are Hormones, And What Do They Do?" What Are Hormones and What Do They Do? | Hormone Health Network. N.p., n.d. Web. 26 Jan. 2017.
2. Baldwin, J., Baldwin, J., and LeVay, S. Discovering Human Sexuality. Massachusetts: Sinauer Associates, Inc. (2009).
3. "Hormonal Contraception." Sex & U. N.p., n.d. Web. 26 Jan. 2017.
4. "Combination birth control pills Why it's done." Mayo Clinic. N.p., n.d. Web. 26 Jan. 2017."Estrogen's Effects on the Female Body." Estrogen's Effects on the Female Body – Health Encyclopedia – University of Rochester Medical Center. N.p., n.d. Web. 26 Jan. 2017.
5. Parenthood, Planned. "Birth Control Methods – Birth Control Options." Methods – Birth Control Options. N.p., 15 Dec. 2016. Web. 26 Jan. 2017.
Last Updated: 9 February 2017.