The Truth About Contraceptives

Why are Contraceptives Immoral and Can They Be Used Therapeutically?

Types of Contraceptives

There are no comprehensive lists, from a Catholic Moral perspective, that distinguish the types of devices, therapies, medications, surgeries from one another. This section will provide general guidelines that can be used to classify contraceptive types. It is important to recognize that there are some devices such as the Hormonal IUD that can fit under multiple categories.

Behavioral Contraceptives

A behavioral contraceptive is any physical action during the course of freely chosen sexual intercourse which is intended to prevent pregnancy while still allowing the pleasure and bonding of sexual intercourse. Such examples include withdrawal and non-vaginal intercourse. 

Barriers and Spermicides

Barriers are devices that are used to prevent sperm from fertilizing eggs during freely chosen sexual intercourse. Condoms, cervical caps, and diaphragms are types of barriers. More recently, some couples have chosen to use menstrual cups in an effort to prevent pregnancy. While this action is contraceptive in nature, it should be noted that most experts agree that it is not effective at preventing pregnancy.

Spermicides are often used in conjunction with barriers, but can be used as a stand-alone contraceptive. Spermicides are liquids, gels, or devices that prevent pregnancy by killing or immobilizing sperm (inhibition of sperm capacitation). Of special note is that there is significant debate regarding the Mechanism of Action (see below) of certain IUDs and some experts believe that they work primarily as a spermicide.

Hormonal Contraceptives

Hormonal Contraceptives are medications, therapies, or devices that use synthetic progesterone (progestin), synthetic estrogen (typically ethinyl estradiol), or a combination of both to prevent pregnancy by blocking or disrupting the normal production of progesterone and estrogen in a woman's body. Despite the use of the name "hormonal," these contraceptives are actually endocrine disrupters which can have significant and serious short-term and long-term side effects (see below). Types of hormonal contraceptives include the pill, patch, ring, shot, implant, and hormonal IUD.

It is important to note that hormonal contraceptives have traditionally been used by women, but pharmaceutical companies have been working to create male hormonal contraceptives. If and when these contraceptives are created, they will also be considered contraceptives.


There are multiple types of Intrauterine Devices (IUDs). The hormonal IUD typically contains a progestin called Levonorgestrel and its actual Mechanism of Action (see below) is not actually known and is highly debated. Mirena is one of the more commonly used hormonal IUDs and the packet insert states that it likely works by "thickening of cervical mucus preventing passage of sperm into the uterus, inhibition of sperm capacitation or survival, and alteration of the endometrium." 

Understanding Mechanism of Action

Understanding Effectiveness Rates

Do Contraceptives Cause Abortions?

Do Contraceptives Cause Breast Cancer?

What are Contraindications?

Common (and not-so-common) Side Effects of Contraceptives

As with any medication, supplement, or medical treatment, it is common to have side effects (unintended/unwanted secondary or adverse effects) from various types of contraceptives. This section will cover common and uncommon side effects and provide links to important research. Where possible, meta-analyses of research (considered the Gold Standard in research will be linked. Due to the rapid output of scientific research, this section may not have the most recent publications.