Contraceptive options: How the rhythm method works
THE rhythm method, also known as the fertility awareness method, is the most natural and oldest form of contraception used by women.
Essentially, what this does is track the menstrual cycle, detect ovulation dates, and is used to determine when to and when not to have sex if your goal is to get pregnant or prevent conception.
“In the rhythm method you abstain from sex during your most fertile days if you want to prevent pregnancy, and have sex on those days if your aim is to conceive. These days are usually determined by the length of your cycle,” said Dr Jordan Hardie, obstetrician-gynaecologist.
But he pointed out that it is an ineffective form of contraception as women may miss a beat of the rhythm.
“If you are fully aware of your cycle and possess the discipline and diligence to only have unprotected sex on your safe days then it may work. But while some women have consistent cycles, some have irregular ones. Also, conception can only occur if an egg is fertilised 24 to 48 hours after the time of actual ovulation. However, male sperm can remain alive and viable in your body for up to five days after ejaculation. So it’s possible to have intercourse up to five days before you ovulate and get pregnant as a result,” Dr Hardie said.
He added: “You’re less likely to get pregnant if you’ve accurately identified your fertile period and avoid unprotected sex on those days each month. Theoretically, this will prevent viable sperm from being present in your reproductive system at the same time as a viable egg. In turn, this will prevent fertilisation and conception.”
The OB-Gyn said the effectiveness of the rhythm method depends on how regular your menstrual cycles are, how reliably you track your menstrual cycles, and how long you abstain from sex around your ovulation date.
He further explained that it is the regularity of the cycles that influence when a woman will ovulate and leads to the weakness in this method.
“A woman’s cycle may vary slightly depending on other factors such as psychological stress, changes in weight, drugs, and other things. If it varies by a day or two it will impact the calculation significantly,” Dr Hardie said.
In relation to benefits, Dr Hardie said the rhythm method is cost-effective, has no side effects, and requires no medication, but the downside is that it does not protect against sexually transmitted infections such as chlamydia, herpes or HIV.
Dr Hardie said it is best to discuss other forms of contraception with an OB-Gyn and with your partner before making a decision.
“You want to know if your partner is up for this. Is your partner faithful? Can you stick to this regimen? Do you have normal periods? Do you understand your period, ovulation time, and other things?”
