Loestrin Birth Control

How Loestrin Works

Like all birth control pills, Loestrin uses hormones to prevent pregnancy. A combination of estrogen and progestin stops ovulation. The hormones also change the environment inside the uterus, making it harder for a sperm to fertilize an egg in case ovulation does occur.

The scientific name for the estrogen in Loestrin is ethinyl estradiol. The progestin is called norethindrone acetate. The estrogen dose is considered the lowest amount that will still provide reliable contraception. Doctors believe that lower amounts of estrogen are safer than higher doses.

Two Versions of Loestrin Birth Control

With regular Loestrin, you take one hormone pill a day for 21 days and placebo pills with no medicine for seven days. During the placebo days, you'll have your period. Periods on the pill are often shorter and lighter than before.

With Loestrin Fe, you take one hormone pill a day for 24 days, then iron pills for four days. Your period comes when you're taking the iron pills. In a study comparing Loestrin Fe to regular Loestrin, women had periods that were even shorter and lighter, often as lasting less than three days.

Shorter Periods with Loestrin Fe

Why does Loestrin Fe cause shorter periods? The "periods" you get on birth control aren't strictly the same as regular menstrual periods. When you're not on the pill, your body releases an egg each month and your uterus grows a thick lining to receive the egg in case it's fertilized. If the egg isn't fertilized, the lining sloughs off in the form of menstrual bleeding.

When you're on the pill, no egg is released. The hormones allow some uterine lining to develop, but it's usually thinner than it would have been. Continuing to take the hormones keeps the lining intact. As long as you're taking pills, you don't get a period. Taking those few extra days of the Loestrin Fe hormone pills causes your period to start later. It also causes the uterine lining to be even thinner, so there's less bleeding.

Doctors say it's all right to have lighter periods when you're taking birth control pills. In fact, another brand, Seasonale, is designed so that you have only four periods a year.

Side Effects

All hormonal birth control has side effects, including Loestrin birth control. Different women will have different reactions to each brand, so sometimes it takes a few tries to find the right fit.

Possible side effects include:

• Breast tenderness
• Fluid retention
• Mood swings
• Weight gain
• Headache
• Nausea
• Melasma (a skin discoloration, especially on the face)
• Abnormal menstrual bleeding, such as spotting between periods

Rarely, a woman using hormonal birth control will develop a more serious side effect, including blood clots, heart attack, or stroke.

Who Should Not Take Loestrin

Some women should not use hormonal birth control. Your doctor will probably not prescribe Loestrin if you have:

• A history of problems with blood clots
• A history of stroke
• Certain types of heart disease
• High blood pressure
• Breast cancer
• Headaches that cause neurological changes

Smoking appears to increase the risk of heart attack and stroke for women using contraceptive pills, so your doctor will probably caution you to stop smoking if you use Loestrin birth control. You may need to stop taking Loestrin, or any form of hormonal birth control, if you need to have surgery and will be on prolonged bed rest. This increases the risk of blood clots.

Safe Sex and the Pill

Loestrin and Loestrin Fe are very effective forms of birth control, but they will not prevent sexually transmitted diseases. Unless you are in a monogamous relationship with a partner who has tested negative for STDs including HIV, it's important to use condoms to protect yourself.