Contraception and Birth Control


We often use the terms “contraception” and “birth control” to mean the same thing. There is a lot of overlap between them, but there are subtle differences, and you owe it to yourself and your body to know them. Before you can understand the differences, you need to understand the basic stages of early pregnancy. Each stage can be prevented or disrupted, so that the pregnancy either never starts or is ended.

 

 

 

Diagram of the Female Reproductive System

uterus labeled

 

 

Definitions of Key Terms

Sexual intercourse – This is how the sperm is introduced to the woman’s body. Both sperm and an egg are needed to create a new life, so if they never meet, there will not be a pregnancy.

 

Conception – Also known as fertilization, this is the moment when the sperm meets the egg. The sperm and the egg combine their DNA and from that moment on, there is a new life. The fertilized egg has a unique genetic code that has never existed before and will never exist again.

 

Implantation – The fertilized egg makes its way through the Fallopian tubes to the uterus, or womb. By the time it gets there, it has divided several times and can have hundreds of cells. The bundle of cells implants in the wall of the uterus, which grows around it to protect and nourish it. At this point, the new life is called an embryo.

 

Contragestion – The prevention of the implantation of the fertilized egg into the uterus. Since the cluster of cells that will develop into a human baby cannot survive without the blood supply from the uterus, if it cannot implant into the uterus, it will cease to grow. Some examples of contragestion include the “morning-after pill” and the Mirena IUD.

 

Abortion – The chemical or surgical ending of a pregnancy after the embryo has implanted in the uterus. At this point, the mother’s body is feeding the growing baby. In order to end the pregnancy, the nourishment to the baby has to be cut off and the baby removed from the uterus, either using medications or surgery.

 

If everything goes the way it is designed to, the fetus will grow inside the uterus for about nine months, attached to that same spot that it implanted. When the baby’s lungs are ready to breathe air, the baby’s hormones signal to the uterus that it is ready to be born, and the mother goes into labor. All of these delicate processes can be interrupted by medications, medical procedures, sexual practices, and other methods. Different types of birth control will affect different parts of this process.

 

 

Contraception

A contraceptive is something that prevents conception. Contraception refers to the medications, devices, or habits that prevent sperm from meeting an egg. Once the sperm has fertilized the egg, it is too late for contraception to function, since conception has already taken place and there is a fertilized egg present. There are two basic forms of contraception: barrier methods, which physically block the passage of the sperm to the egg, and hormonal methods, which interfere with the release of the egg by the ovary.

 

 

 

 

Barrier Methods

 

Barrier methods, such as condoms, prevent the sperm from getting past the cervix. The sperm never meets the egg, so the egg cannot be fertilized.
Barrier methods, such as condoms, prevent the sperm from getting past the cervix. The sperm never meets the egg, so the egg cannot be fertilized.

 

 

 

Hormonal Methods

 

Eggs are released from the ovaries ready to be fertilized. Many hormonal contraceptives work by preventing the release of the egg.
Eggs are released from the ovaries ready to be fertilized. Many hormonal contraceptives work by preventing the release of the egg.

 

  • Withdrawal method – sperm never enters the female’s body
  • Natural Family Planning (NFP) – by tracking the female’s fertility, sperm is only introduced when there is no egg present to fertilize
  • Male and Female condom – prevents sperm from meeting the egg
  • Spermicides – kills the sperm before it reaches the egg
  • Contraceptive sponge – kills the sperm before it reaches the egg
  • Diaphragm – prevents sperm from meeting the egg
  • The Pill – prevents the female’s body from releasing an egg
  • Contraceptive injection (The Shot) – prevents the female’s body from releasing an egg
  • Contraceptive ring (NuvaRing) – prevents the female’s body from releasing an egg
  • Contraceptive patch – prevents the female’s body from releasing an egg

There are also two forms of permanent contraception, each of which involves a small surgical procedure:

  • Tubal ligation (permanent) – prevents sperm from meeting the egg
  • Vasectomy (permanent) – prevents the male from releasing sperm during sexual intercourse

The “Morning-After” Pill

The morning-after pill (sold under the name “Plan B” or “Plan B One-Step”) is a concentrated dose of hormones that can be taken up to 72 hours following sexual intercourse. Multiple studies try to prove exactly how this pill works to prevent pregnancy, and many of those studies contradict each other.

 

What is known about Plan B:

  • if you have not yet ovulated, the hormones in Plan B will prevent ovulation
  • if you have already ovulated, Plan B will not prevent fertilization of the egg
  • if you are already pregnant and the embryo has implanted in your uterus, Plan B is unlikely to affect your pregnancy

 

What is not known about Plan B:

  • whether it changes the uterine lining so that the fertilized egg cannot implant, resulting in an early abortion
  • whether it thickens the mucus of the cervix to slow down the sperm

We encourage you to do your own research before you use any birth control method. You deserve to know what you’re putting in your body, and what effect it will have on you.

 

Birth Control

Birth control is similar to contraception, except that it has the broader definition of preventing birth rather than preventing conception. Contraception is one form of birth control,  and there are other types of birth control (methods that prevent birth) as well. Contragestives work by preventing implantation into the walls of the uterus. Chemical abortions work by forcing the uterus to reject the implanted, growing embryo. Surgical abortions work by physically tearing the baby out of the uterus. All non-contraceptive birth control works at the level of the uterus and the uterine lining.

 

Contragestive Birth Control and Abortion

contragestive

 

Most Common Types Of Non-Contraceptive Birth Control:
  • Mifepristone – the “abortion pill,” formerly known as RU-486, blocks the action of the hormones (specifically progesterone) that keep the embryo nourished after it implants. It is usually combined with another medication that causes contractions, so that the uterus will push the embryo out once it has died. Also called “chemical abortion” or “medical abortion.”
  • Intrauterine Device (IUD) – There are two types of IUD. The Mirena IUD has hormones that function similarly to the Pill, but in much lower doses that make it less effective at stopping the release of an egg. It counters that by making the uterus unable to sustain a pregnancy, so the fertilized egg can’t implant in the uterine wall. The other type is the Paragard IUD, which has no hormones in it but is made of copper. The copper is poisonous to sperm and prevents most of them from reaching the egg. The copper also makes the uterus unwelcoming to the fertilized egg, so it cannot implant.
  • Implants (Implanon) – This birth control functions in three ways, two of which are contraceptive and one of which is contragestive. It works like the Pill by preventing the release of an egg through the use of artificial hormones. It also makes the mucus at the entrance to the uterus thicker, so it is more difficult for the sperm to get through and fertilize the egg. Finally, it makes the uterus unwelcoming to the fertilized egg, so it cannot implant.
  • Surgical Abortions – Surgical removal of the embryo or fetus.

 

There are many options that involve taking hormones to effect changes in your menstrual cycle. It is important to remember that every woman’s body is unique and responds differently to hormones. There are serious side effects that can occur when you take artificial hormones, and these should always be supervised by your doctor.

 

When you are researching how different types of birth control function, also note that there is conflicting information from various studies that have been done on these different options. All hormonal contraceptives have the possibility of changing the lining of the uterus, which can lead to the death of an embryo. The only 100% effective form of birth control is not to have sex. Also, many forms of birth control work in multiple ways, both contraceptive and contragestive. Do some research; know your options.

 

If you have questions about these birth control options or understanding your menstrual cycle, please Make an Appointment. We would be happy to teach you more about the incredible intricacies of your reproductive system. Please note that LivingWell Pregnancy Centers cannot prescribe birth control.