Depo Provera

A woman in my parish is considering using Depo Provera. Her doctor told her that it is a contraceptive because it does not end the human life that has already begun in her womb. What is the truth regarding Depo Provera?

Depo-Provera is one of a class of steroid hormones that employ powerful hormones to control the female reproductive system. Others in this class include the intra-uterine device (IUD), birth control pills or oral contraceptives (OCs), the morning-after pill (MAP) and emergency contraception (EC), and the implantables (Norplant, Jadelle and Implanon).
Depo Provera's active ingredient is depot medroxyprogesterone acetate (DMPA), a synthetic form of the natural hormone progesterone. Upjohn Pharmaceuticals is the corporation that produces Depo-Provera. According to Upjohn's patient information pamphlet on Depo Provera, the compound "inhibits the secretion of gonadotropins which, in turn, prevents follicular maturation and ovulation and results in endometrial thinning. These actions produce its contraceptive effect."1
The pamphlet also says that Depo Provera:

• "[Has a] contraceptive effect produced by inhibiting the secretion of gonadotropins (FSH, LH), which prevents follicular maturation and ovulation.
• Suppresses the endometrium [the mucous membrane lining the uterus] and changes cervical mucus."

In other words, Upjohn acknowledges that Depo Provera acts as an abortifacient.
The authoritative Contraceptive Technology confirms that Depo Provera has a three way mode of action. It inhibits ovulation and thickens cervical mucus (which are both contraceptive actions), but it also alters the endometrium (the lining of the uterus) so that its degree of receptivity to the blastocyst (very early developing human being) is significantly decreased.
According to Contraceptive Technology, "Other contraceptive actions include the development of a shallow and atrophic [thinning] endometrium ..."
When Depo Provera works in this way, it is an abortifacient.2

1. Patient information brochure. "Now Available in the U.S.: Depo Provera Contraceptive Injection." Upjohn Pharmaceutical Company, December 1992.
2. Robert A. Hatcher, et.al. Contraceptive Technology (18th Revised Edition) [New York: Ardent Media, Inc.], 2004. Chapter 20, "Depo Provera Injections, Implants, and Progestin Only Pills (Minipills)," pages 461 to 494.

These and other question are answered in HLI's Little black book for priest.