DMPA-SC — Get insight on contraceptive shot
The young woman waiting in your exam room has indicated she would like a method of long-term contraception, but she says she has experienced estrogen-related side effects from previous pill use. What options can you offer her?
U.S. clinicians can prescribe a new form of progestin-only contraception: Depo-SubQ Provera (DMPA-SC, Pfizer, New York City). The subcutaneous form of the contraceptive injection depot medroxyprogesterone acetate (DMPA) has been widely available in the United States since May 2005, says An Phan, Pfizer spokeswoman.
"Response has been very positive," she reports. "Doctors have told us they like a lower-dose product."
Depo-SubQ Provera 104 is designed to be administered subcutaneously, not intramuscularly, as with the conventional quarterly injection of DMPA. Both drugs are administered every three months to achieve contraceptive efficacy. Each injection of DMPA-SC contains 104 mg medroxy-progesterone acetate, DMPA contains 150 mg.
DMPA-SC offers an excellent pregnancy prevention rate and comparable side effect profile to DMPA, says John Jain, MD, associate professor of obstetrics and gynecology at the University of Southern California Keck School of Medicine in Los Angeles.
Results from two large open-label, Phase III studies conducted in North and South America, Europe, and Asia point to the drug’s effectiveness; they report zero pregnancies in 16,023 women-cycles of exposure.1 Women in the studies had a broad range of body weights. The absence of pregnancies across all categories of body mass index (BMI) suggests that no dosage adjustments are needed for higher BMIs.1
DMPA-SC now carries approval from the Food and Drug Administration (FDA) for management of pain associated with endometriosis, a gynecological condition that affects one in 10 women of reproductive age. The drug, which gained FDA approval for the indication in March, is the first new treatment option for endometriosis pain in 15 years, according to Pfizer.
At least 5.5 million women in North America alone have endometriosis.2 The condition occurs when excess endometrial tissue of the uterus migrates and implants in other areas of the body, such as on the ovaries, fallopian tubes, and other organs in the pelvic region. Its major symptoms include pelvic pain, particularly during the menstrual cycle. About 30% to 40% of women with endometriosis are infertile, which makes it one of the top three causes for female infertility.2
In an 18-month study involving 274 patients, DMPA-SC was statistically equivalent to Lupron (leuprolide acetate, TAP Pharmaceuticals, Lake Forest, IL) across all endometriosis-associated pain categories including pelvic pain, pelvic tenderness, painful periods, painful intercourse, and hardening/thickening of tissue.3 Researchers conclude that DMPA-SC 104 reduces endometriosis-associated pain as effectively as leuprolide with less decline in bone mineral density (BMD).3
Counsel on black box’
Side effects for DMPA-SC are similar to other progestin-only methods, says Jain. Irregular uterine bleeding, such as spotting and prolonged bleeding, is common during the first three months of use; however, such bleeding usually diminishes over time. Most women using DMPA or DMPA-SC become amenorrheic.4 In one study of DMPA-SC, amenorrhea increased from 26% during month three to 55% during month 12.4
DMPA-SC carries the same "black box" warning as DMPA regarding the drug’s potential impact on bone mineral density. The injectable contraceptive should be used as a long-term birth control method (longer than two years) only if other birth control methods are inadequate, the label advises. Women who continue to use the drug past the two-year mark should have their BMD evaluated.
One promise of DMPA-SC may lie in its potential for self-injection, which would allow patients to self-administer the drug instead of returning to a provider’s office. Researchers looking at the acceptability of such administration report that many women would prefer such an option. In a questionnaire survey of 176 women currently using DMPA, 67% said they would like to self-inject.5 In a second survey, 26% of women who had never used DMPA and 40% of ex-users said they would seriously consider DMPA if self-administration were possible.5
Women will have to wait for this option, though. Pfizer is not pursuing such an indication for DMPA-SC at this time, says Phan.
References
- Jain JK, Jakimiuk AJ, Bode FR, et al. Contraceptive efficacy and safety of DMPA-SC. Contraception 2004; 70:269-275.
- National Institute of Child Health and Human Development. Endometriosis. Accessed at: www.nichd.nih.gov/publications/pubs/endometriosis/index.htm.
- Crosignani PG, Luciano A, Ray A, et al. Subcutaneous depot medroxyprogesterone acetate versus leuprolide acetate in the treatment of endometriosis-associated pain. Hum Reprod 2005 Sep 21; [Epub ahead of print]. Accessed at: humrep.oxfordjournals.org/cgi/content/abstract/dei290v1.
- Jain JK. Subcutaneous depot medroxyprogesterone acetate for birth control and endometriosis pain. OBG Management 2005; accessed at: www.obgmanagement.com/content/obg_featurexml.asp?file=2005/08/obg_0805_00033.xml.
- Lakha F, Henderson C, Glasier A. The acceptability of self-administration of subcutaneous Depo-Provera. Contraception. 2005; 72:14-18.
You have reached your article limit for the month. Subscribe now to access this article plus other member-only content.
- Award-winning Medical Content
- Latest Advances & Development in Medicine
- Unbiased Content