A girl who uses the birth control shot (also known as depot medroxyprogesterone [DMPA] or Depo-Provera) to prevent pregnancy receives a shot of a long-acting form of progesterone about once every 3 months. Despite the convenience of this method of birth control, many teens who stop using it say they do so because they gained weight. Researchers from Case Western Reserve University in Cleveland, Ohio, conducted a study to understand more about the relationship between the birth control shot and weight gain in teen girls.
Researchers interviewed 290 12- to 18-year-old girls who'd requested contraception at a city health clinic. Teens chose either the birth control shot or the birth control pill and underwent checkups about 6, 12, and 18 months after starting birth control. Each teen had her height and weight measured throughout the study. Later, researchers compared the teens using birth control with a group of teen girls who didn't use contraception.
In teens who weren't obese prior to taking contraceptives, both the pill and the shot didn't really affect weight. But teen girls who were obese at the time they started taking the birth control shot gained significantly more weight than obese girls who took the pill or used no birth control. After 18 months, obese girls taking the birth control shot gained about 21 pounds (9.2 kilograms), compared with only half a pound (0.2 kilograms) in obese girls who'd taken the pill and about 7 pounds (3.1 kilograms) in girls who'd not taken any birth control.
What This Means to You: The results of this study suggest that girls who are obese and receive the birth control shot are at significant risk for additional weight gain. If your daughter needs contraception and she's unsure of which method to choose, she should talk to her primary doctor or gynecologist. He or she can take into account your daughter's weight, birth control needs, and suggest a form that's best for her. If your daughter already receives the birth control shot, she should also be using a condom during sexual activity because the shot does not offer any protection against sexually transmitted diseases.
Source: Andrea E. Bonny, MD; Julie Ziegler, MA; Ray Harvey, MPH; Sara M. Debanne, PhD; Michelle Secic, MS; Barbara A. Cromer, MD; Archives of Pediatrics and Adolescent Medicine, January 2006.
Reviewed by: Steven Dowshen, MD
Date reviewed: January 2006