For around 50 years now, women have been taking the birth control pill to prevent pregnancy – but are they aware of all the potential side effects?

Speaking to ABC News, Dr Nanette Santoro of Albert Einstein College of Medicine describes how doctors do not always discuss possible side effects of the pill with patients.

For example, some women taking this combination of estrogen and progestin may experience a slowdown in their libido, mood changes and some changes in their sinuses.

Furthermore, those who take the pill have reported side effects that are similar to conditions noted by pregnant women.

These include heartburn, constipation, sleep disturbances and changes in weight.

“Because the pill in a lot of ways produces a pseudo-pregnant state, some of the side effects of pregnancy are noticed in the pill,” Santoro told the news provider.

She also warned that smokers – particular those over 35 – should be discouraged from taking birth control pills altogether, because of connections to high blood pressure.

Some women who are not comfortable taking hormones to prevent pregnancy have used natural health resources – such as the rhythm method – instead.