Posts tagged ‘estrogen’
Progesterone In Your Pill: If the shoe fits, wear it!
So, what makes one combination oral contraceptive pill (OCP) different from another? What’s the difference between brand-name and generic versions, if any?
The answer generally boils down to one word: progesterone. How do we know this? Because the chemical composition of the estrogen component of almost every OCP marketed in the U.S. is exactly the same. It’s ethinyl estradiol. The only thing that changes from pill-to-pill is the dose (thus the idea of “low dose” pills, “triphasic” pills etc), as described in my previous post.
So, although all “low dose” OCP’s may contain 20 micrograms of estrogen, there are dozens of different kinds because each manufacturer uses one of eight different kinds of progesterone in each type of pill.
Progesterone
The type of progesterone is indicated by the second word in the pill’s generic name. For example, Loestrin is ethinyl estradiol and NORETHINDRONE. Other pills have other progesterone components (i.e. Ortho-Tri-Cyclen and Ortho-Tri-Cyclen-Lo contain NORGESTIMATE, Yasmin andYaz contain DROSPERINONE). You get the idea.
So, why do we need so much variety? Can’t everyone just use the same pill in different doses? Like Advil or Tylenol, just use a higher dose if you need more of it?
Well, it’ s not that simple. The dose isn’t the important thing (it’s usually low, about 1-2 mg). It’s the differences in the chemical characteristics of the progesterone that make each pill unique and separate it from its similar contraceptive cousins.
Some progesterones have a higher level of “progestational activity.” This means the degree to which it binds with progesterone receptors in the body. In addition to preventing pregnancy, stronger progestational agents can lessen menstrual bleeding, reduce acne, lessen excessive hair growth, etc.
Some progesterones have an effect on blood levels of potassium or cholesterol. Some can increase a person’s risk of blood clots. These risks and benefits are an important topic to discuss with your gynecologist (or other prescriber).
As if things weren’t confusing enough, generic OCP’s have active ingredients (estrogen and progesterones) which are chemically identical to the brand-name version. They are, however, made by different manufacturers. They may contain different additives or be formulated in a slightly different way.
That’s why some people find that, while the brand name version worked well for them, different symptoms occur when they switch to the generic version(or vice-versa). This means you may need to pay more (or less) for the version you prefer. The cost difference can be significant ($50 or more!), so consider the choice carefully.
It’s often difficult to predict which oral contraceptive (and which progesterone) will work best with a particular person’s chemistry. While your gynecologist (or other provider) can often guide you toward picking an oral contraceptive which is the most likely to satisfy your partiuclar needs, sometimes, it’s necessary to try out a few different types before you hit on a pill that you like.
But when you do… Wow. It’s like Cinderella fitting perfectly into that glass slipper and living happily ever after. And not getting pregnant on that pumpkin-carriage ride home.
Happily Ever After
Why are there so many different types of oral contraceptives? – The Estrogen Equation
Well, if you’ve read my previous post (which I’m sure you did!) you already know that the two main components of combined OCP’s are estrogen and progesterone. What makes each type of pill distinct is the way in which these two components are dosed and formulated. In this post, let’s discuss only the estrogen component. We can talk about the progesterone later.
Combination OCP’s can be described as low-dose, medium-dose or (rarely) high-dose. This refers to the dose of estrogen in the tablet. A low-dose pill usually contains 20 micrograms of estrogen. Medium dose pills contain between 30 and 35 micrograms. Higher doses can go up to 50 micrograms.
Why does it matter? Well, a low-dose pill is great for somebody who needs the pill for pregnancy prevention, but doesn’t require the higher doses needed to suppress other conditions (like endometriosis or excessive menstrual bleeding). A low dose of estrogen also minimizes the risk of complications from oral contraceptives (such as an increased risk of blood clots and other potentially life-threatening medical conditions).
So, why wouldn’t everyone choose to take a low-dose pill? Some women taking low-dose pills may not have bleeding during the week of placebos (inactive pills) because the low dose of estrogen keeps the lining of the uterus (womb) very thin. Therefore, little tissue is shed (as menstrual flow) when the body withdraws from the estrogen. Amenorrhea (absence of a period) can be normal and healthy in this situation and is not a cause for concern in the absence of other symptoms.
In some women, bleeding between periods (metrorrhagia) may occur when the dose of estrogen is too low to stabilize the lining of the uterus between cycles. If this occurs, it doesn’t mean the pill isn’t protecting you against pregnancy. It just means you may need to switch to a different pill in order to reduce inconvenient or unpredictable bleeding.
Spotting or mid-cycle bleeding can also be more likely to occur on a low-dose pill if doses are missed or are taken late. Therefore a low-dose pill may be a poor option for women who can’t manage to take their pill on time every day. Obviously, back-up contraception (a condom, perhaps?) should be used when necessary.
Oral contraceptives with 30 to 35 micrograms of estrogen may be a better choice for women who need to suppress their menstrual cycles because of endometriosis, pelvic pain, excessive menstrual bleeding (menorrhagia), or who have had irregular bleeding on lower dose oral contraceptives.
If they dose of estrogen is the same in every pill, the type of pill can be called “monophasic.” Some oral contraceptives have a dose of estrogen which varies from the first to the third week (triphasic). These pills are meant to mimic the natural variation in hormones that occurs during a normal menstrual cycle. Whether a monophasic or a triphasic pill is right for you will depend on a number of factors which you may wish to discuss with your gynecologist.
The Gynecologist 