The Mini Pill

The term "the mini-pill" refers to the progestogen-only pill (POP) designed to prevent pregnancy. The mini-pill contains synthetic progestogens and, if taken as directed, is 99% effective in preventing pregnancy.

The mini-pill is usually prescribed if the combined contraceptive pill is not considered suitable, for example if the woman suffers from certain health conditions or is a smoker. This pill is safer for such women because it does not contain oestrogen.

How does the POP work?

The POP prevents pregnancy in two ways. Firstly, it makes the mucous that is made by the cervix thicker at the neck of the womb, which makes it harder for the sperm to reach an egg. It also makes the lining of the womb thinner, so if an egg was fertilised it would not be able to implant itself in the wall of the womb to grow.

In some cases, the progestogen-only pill also prevents ovulation, which means an egg is not released from the ovaries.

Is this an effective form of contraceptive?

The mini-pill is only marginally less effective in preventing pregnancy than the combined contraceptive pill. For every 100 women who take the mini-pill correctly, less than two will fall pregnant. This is around the same level of protection as the contraceptive coil. It is worth noting that the newer progestogen-only pills, such as Cerazette, have lower failure rates. Whichever POP you take, it is critical to take each tablet at the same time every day.

What are the benefits?

The progestogen-only pill has many of the same benefits as the combined contraceptive pill, such as convenience and effectiveness. An added benefit of the POP is that it is safe for use by women who cannot take the combined contraceptive pill, due to the oestrogen it contains. The mini-pill is also safe for breast-feeding women. Due to the lack of oestrogen, there are fewer side effects associated with the mini-pill such as nausea, headaches, depression and blood pressure changes.

Should I worry about side effects?

There are far fewer side effects for those taking the mini-pill than any other birth control pill. If side effects do occur, they are usually brief and mild and could include mood changes, reduced libido, breast tenderness and increased acne.

If you have a history of liver disease, breast cancer, ovarian cysts or unexplained vaginal bleeding, you may not be suitable to take this progestogen-only pill.