Contraceptive Pearl: Birth Control Patches
Updated November 29th, 2022
The three birth control patches available in the US deliver estrogen and progestin transdermally. Some people find a once-weekly patch easier to remember than a daily pill.
The newest patch, Twirla, contains lower doses of hormones:
Brand Name | Estrogen | Progestin |
---|---|---|
Xulane | 35 mcg | 150 mcg norelgestromin |
Zafemy | 35 mcg | 150 mcg norelgestromin |
Twirla | 30 mcg | 120 mcg levonorgestrel |
All three patches carry a boxed warning from the Food and Drug Administration (FDA) about smoking and body mass index (BMI). The FDA recommends against the patch for all smokers over the age of 35, and for anyone whose BMI is over 30. The Medical Eligibility Criteria for Contraceptive Use (MEC) from the Centers for Disease Control and Prevention (CDC) differs in its approach, giving the patch a MEC category 3 or 4 (relative/absolute contraindication) for smokers over age 35 depending on how many cigarettes they smoke. The MEC gives the patch a 2 (mild caution) for people with a BMI over 30, acknowledging a higher risk for thromboembolism but noting that the absolute risk remains small.
A phase 3 clinical trial of Twirla enrolled 2032 people, 35% of whom had a BMI over 30. The most common adverse effects were nausea and headache. Eleven percent of participants stopped using the patch due to side effects. Three participants (0.4%), all with BMI over 30, had a deep vein thrombosis and pulmonary embolism during the trial. The study participants’ pregnancy rate also rose with higher BMI.
There are some additional considerations that are unique to the patch. People who swim for longer than 30 minutes at a time may find that the patch detaches. Swimmers may want to choose a different method. Additionally, the color of the patch is made to reflect lighter skin tones. People with darker skin tones may not feel comfortable wearing the contraceptive patch.
Resources:
Your Birth Control Choices Fact Sheet
Medical Eligibility Criteria for Initiating Contraception
Sources:
Pharma-free
The Reproductive Health Access Project does not accept funding from pharmaceutical companies. We do not promote specific brands of medication or contraception. The information in the Contraceptive Pearls is unbiased, based on science alone.