Can switching birth control cause you to have lighter periods?
Yes. In general, hormonal birth control methods that contain both estrogen and a progestin (birth control pills, the patch, NuvaRing) decrease the number of days of bleeding and the amount of blood women lose each cycle. Since these methods all have varying levels of estrogen and progesterone in them, a change from one kind of birth control to another can also change the days and amount of flow.
During a normal menstrual cycle, hormones cause the uterus to build up a thick lining with a lot of blood vessels called the endometrium to create a welcoming environment for a fertilized egg to attach. If conception doesn’t happen, the hormone levels drop, the blood vessels shrink and the endometrium sloughs off. Voila – you have a period! Hormonal birth control causes the endometrial lining to be thinner than normal, so there is less to shed each month. In fact, there may be no fresh blood at all. A period could be just a drop of blood, or a brown smudge.
On the other hand, if you are using a birth control method that contains only a progestin and no estrogen (Depo Provera, Nexplanon implant, Mirena IUD, or “mini-pill”) you are more likely to experience irregular bleeding. Many women experience either an increased number of days of light bleeding or no bleeding at all.
It’s a good idea to check in with your health care provider after your first 3 months on the pill to make sure everything is going OK. If your pattern of bleeding concerns you be sure to see her to rule out the possibility of pregnancy, infection or other medical conditions. Remember, not all bleeding can be blamed on birth control!
If you have any questions or concerns about birth control, the clinical staff of our Women’s Services Department is always happy to see you!
Beth Askue, MS, CNP
Student Health Services
The Ohio State University