Pregnancy

Women who wish to become pregnant can simply stop taking the pill; there is no need to finish the current pack. Pregnancy may take some time, especially if a woman had irregular periods before starting the pill. But use of birth control pills does not decrease the odds of pregnancy once a woman discontinues usage.

Post-pill Amenorrhea

Some women do not resume regular periods after stopping birth control; this is called post-pill amenorrhea. It may take up to three months for your body to start producing the hormones that cause regular periods.

Libido

Some women decide to stop taking birth control due to a decrease in their sex drive. A study by researchers at Boston University's medical school in 2005, however, shows that this lack of libido does not immediately resolve itself; low levels of testosterone were reported up to a year after stopping the pill.

Weight

Some women find that the pill causes them to gain weight. Stopping birth control can cause less water retention in some women, leading to the loss of this weight.

Other Effects

Some women take birth control to ease PMS symptoms and clear up acne. If taking the pill resolved these problems, stopping birth control may lead to a recurrence of them.

Source:

Information about Birth Control

Informaton from the Mayo Clinic about Birth Control

The Pill and Libido