Whether Sharna Burgess used an oral contraceptive or not, a few factors other than time play into why it could have failed.
If she had been taking over-the-counter allergy medication, the efficacy of Burgess’ birth control could have dropped. “I personally noticed that pseudoephedrine causes breakthrough bleeding,” Dr. Sophia Yen exclusively told The List. “This is most likely because it revs up the liver and the liver eats through the birth control pills faster.” Pseudoephedrine is most commonly known as Sudafed. According to Dr. Yen, St. John’s Wart and activated charcoal, used most often if you need to get your stomach pumped, also puts you at risk for birth control failure.
But there could be another reason why Burgess ended up pregnant: her genes. In 2019, a new study was published that showed how metabolism factors into how protected a woman is by the birth control pill. According to Reuters, the study shows that some birth control users “may inherit genes that break down contraceptive hormones more rapidly,” which keeps the hormone level of the pill you’re on — progestin-only or a combination — too low to prevent pregnancy.
“Knowing that there is a difference in how people metabolize hormones sets the stage for more research that can help us … give the right medication to the right patient,” Dr. Anne Davis, an obstetrician-gynecologist at NewYork-Presbyterian/Columbia University Irving Medical Center told Reuters.
The problem with solving the mystery of Burgess’ and many other pregnancies that happen despite birth control is that there still hasn’t been enough research done to understand.
