The Pill Today
How it works
How it should be used
Side effects
Today's pill types
Schering's newest pill 

How the pill works
The basic principle of the pill is a brilliant scientific idea. Hormones make the body "think" that there is a pregnancy, so ovulation is inhibited. The pill works both centrally in the brain and peripherally in the ovaries, the Fallopian tubes and the womb (uterus). Hormonal contraceptives inhibit the two key hormones that induce ovulation. At first, the release of Follicle Stimulating Hormone (FSH) is inhibited. This hormone is responsible for maturation of the egg. In addition, the pill inhibits the release of Luteinizing Hormone (LH). This substance normally induces ovulation in the middle of the cycle.
The natural production of both hormones starts when the levels of progesterone and estrogen are low. But since both substances are contained in the pill, the FSH/LH production cycle cannot get started.
The estrogens in the pill ensure a stable 28-day cycle with no intermenstrual bleeding. The progestin inhibits the maturation of the egg in the ovary, so no ovulation takes place. In addition, the mucus in the neck of the uterus (cervix) is thickened, so male sperm have no chance to get through.

How it should be used
Hormonal contraception is very simple to use: You take one pill a day, roughly at the same time every day. The only thing to remember is regularity, because otherwise the hormone balance will be disturbed. Usually, a woman will start the pill on the first day of the normal menstruation, and then continue for 21 days. Then there will be a one-week break. 
During this time there will usually be a menstruation-like withdrawal bleeding, which however is weaker and less painful than a normal menstruation. After the one-week break, the 21-day rhythm starts again.
Note: The time between two pills during the intake phase must not be longer than 36 hours. The progestin-only pill must be taken at the same time every day (with no more than 24 hours between two pills) while with other (combined) pills a variation of up to twelve hours can be tolerated. 
Another important point: Vomiting within two hours of pill intake, severe diarrhea or intake of certain concomitant medications can compromise the contraceptive efficacy. In these cases, additional other non-hormonal contraceptives should be used.

Side effects of the pill
The pill is a very effective medication, that's why it is available only on prescription. A woman who wants to use the pill for contraception must therefore visit a doctor. Before prescribing the pill, the doctor will try to find out possible risk factors from the woman's medical history. 
But the hormone content of the pill has been reduced more and more in the last 40 years, and the balance between estrogens and progestins has been changed. Thus, unwanted side effects could be reduced further and further.

Unwanted side effects
Although the pill in most cases is very well tolerated, sometimes there are unwanted side effects such as slight nausea, breast tension, slight headaches, transitory increase of weight, possibly slight loss of libido and a small increase in the risk of thrombosis.

Desired side effects
Scientists agree that the beneficial side effects of modern ovulation inhibitors far outweigh the unwanted effects. For example, menstrual anomalies are corrected, dysmenorrhoea (painful menstruation accompanied by colic-like abdominal pain) is greatly reduced. The pill can reduce iron deficiency anemia and protects from cysts in the ovaries and in the breast. Some other important effects include the beneficial effect on certain malignant tumors, a reduction of inflammatory and rheumatic diseases, a reduction of pregnancies outside the womb (so-called ectopic pregnancies) and positive effects on the skin, e.g. in acne and oily skin (seborrhea).

The different types of pills
All pills are not created equal. They differ in the type and dosage of the hormones used. When the first pill Enovid® was introduced in the US, it contained 80-100 micrograms of estrogen. Only one year later, Schering's Anovlar® had 50 micrograms. Modern pills today – like e.g. Yasmin® - contain an even lower dose (20-30 micrograms). While the estrogen is the same in all pills (only the dosage is different), there is a difference between the preparations because of the progestin and its dosage.

Classic combined pills 
These pills contain both estrogen and progestin. If the estrogen content is less than 50 micrograms per day, the preparation is called "low-dosed" or micropill. Monophasic low-dosed pills, which contain the same amount of both estrogen and progestin in all 21 active pills (e.g. Yasmin® or Mirelle®) are not only effective and well tolerated, but some can also help with cosmetic problems such as acne and oily hair. 

Triphasic pills (e.g. Triquilar® and Milvane®) are also low-dosed pills. The special feature of triphasic pills is that they contain estrogen and progestin in varying dosages. 

Sequential pills contain only estrogen in the first phase, adding progestin in the second phase, while biphasic pills like Sequilar® have a very low dose of progestin in the first phase as well. Sequential and biphasic pills contain 50 micrograms of estrogen and are therefore not "low-dosed".
Combined pills have a Pearl index of 0.1-0.7 and are thus exceptionally effective. (The "Pearl Index" measures the efficacy of a contraceptive method. It counts the number of pregnancies when one hundred couples use the pertinent method for one year.)

POP (Progestin-only pill)
The POP, sometimes also called minipill, contains only progestin at a very low dosage. The result: Ovulation is usually not inhibited. The contraceptive efficacy stems mainly from the POP's effect on the lining of the womb (endometrium) and, even more important, on the thickening of the mucus in the neck of the womb. This is the reason that the POP only achieves a Pearl index of about 3 and is less effective than low-dosed combined pills.
However, it is very important to take the POP punctually at the same time every day. With perfect use, a Pearl index of 0.5 is possible.

Schering's newest pill
After 40 years of research and development, it seems impossible to improve the pill any further. It is safe and well tolerated. However, by developing Drospirenone Schering has created a completely unique progestin. Not only is it well tolerated, it also offers several other interesting features. No other progestin has a molecular structure comparable to the 17a-spirolactone Drospirenone. As unique as the structure is the effect. Drospirenone is very similar to natural progesterone. It has antiandrogenic properties and thus counteracts excessive reactions to male hormones. In women, these hormones can, among other things, cause oily skin with breakouts, and acne. However, what is really innovative about Drospirenone is another effect: The pill containing Drospirenone reduces estrogen-induced water retention in the body. Thus the great fear of pill-induced weight gain is finally lifted.