A new study suggests females who take a certain type of birth control pill may be more vulnerable to certain sexually transmitted diseases.
Researchers from the University of Newcastle in Australia say the mini-pill, which only contains the hormone progesterone, can impact levels of a protein that can boost immunity to STDs such as chlamydia and herpes.
According to ABC News, the protein - interferon epsilon - is produced in the female reproductive tract and is regulated by hormones. Progesterone causes levels of the protein to drop, making individuals more susceptible to STDs.
However, scientists say that birth control pills that contain both estrogen and progesterone don't impact interferon epsilon because they cancel out the decrease caused by the progesterone.
They also conclude that their findings may lead to the development of new mini-pills that will neither impact the protein nor make people more susceptible to STDs, as well as vaccines that could boost immunity.
"Since this protein boosts female reproductive tract immune responses, it's likely, although we haven't addressed it directly, that this finding will be important for other infectious diseases like HIV and HPV," lead researcher Paul Hertzog told the news provider.
Chlamydia is a common STD that is caused by a bacteria. According to the Centers for Disease Control and Prevention, it is the most prevalent STD in the U.S., infecting an estimated 2.86 million individuals each year. It can infect both men and women and can be transmitted from pregnant women to their babies during childbirth. If left untreated, it can cause serious health problems, including infertility.
It is often referred to as a "silent" infection because most individuals with chlamydia don't have any symptoms. However, asymptomatic people can still transmit the STD to others.
Chlamydia can be diagnosed through laboratory tests such as a genital swab or urine test. It can be cured with antibiotics.