Remember those two hormones we learned about earlier? Estrogen and progesterone. That’s what hormonal birth control uses to override the menstrual cycle. You’ll also remember that the trigger for ovulation is a surge of hormones from the brain. That’s because the brain ultimately controls the menstrual cycle. However, when estrogen and progesterone are taken as medication, it fools the brain into giving up control of the ovaries, and the brain hormones don’t surge to trigger ovulation. That’s essentially how hormonal birth control works, by preventing the release of an egg from the ovaries. If there’s no ovulation, there’s no chance of pregnancy. 

Hormonal birth control isn’t perfect. There’s always the possibility an egg will be release and fertilized during a menstrual cycle. If this occurs, the uterus lining will be less favorable for implantation due to secondary effects of the hormones in preventing pregnancy. If your view of personhood begins at fertilization, you may not be comfortable with this possibility. This is why many churches take the official stance that using hormonal birth control is morally wrong.

THE PILL

The most popular form of hormonal birth control is what doctors call oral contraceptives (OCP), but we’ll just call The Pill. It’s a tablet, containing both estrogen and progesterone, taken daily for three weeks to prevent ovulation. Then there’s a “sugar pill” (without hormones) for a week to trigger menstruation – the drop off of hormones signals the time for your period to start. Packages of birth control pills have enough pills for four weeks of medication, but only three weeks’ worth have actual hormones. You just have to take a pill every day, and the cycle will sort itself out.

As we stated, the main way birth control pills work is by preventing ovulation. That’s what estrogen does. However, the progesterone component also thickens the mucus plug in the cervix (to help block sperm from entering the uterus) and makes the uterine lining less favorable to implant an embryo, on the off-chance ovulation and fertilization occurs. 

Overall, birth control pills are about 93% effective. Most failures are due to not taking the pills every day, especially in the first week of the cycle.

Birth control pills can help with a number of other medical conditions besides preventing pregnancy. Acne is one of them: your skin typically improves when on hormonal birth control. Menorrhagia is another.

Menorrhagia, what a fitting term. Women who suffer from this have raging periods: painful cramping and heavy bleeding that causes them to miss school/work. The bleeding can be so bad that it causes anemia (low blood count). Symptoms can be debilitating. If this is you, know that there’s help available. Talk to your doctor.

Historically, the dose of estrogen in birth control pills was really high, causing all sorts of nasty side effects. Over time, the dose has decreased, making The Pill much more tolerable. Side effects are usually mild and short-lived. Breast tenderness, nausea, bloating, and irregular bleeding are common but usually subside. Coming off of birth control pills can be miserable for a few months until your body gets used to cycling on its own again. However, one of the most common complaints is “I just don’t like how they make me feel.” Simple as that. “Moody” or “icky” or “just weird” – some women don’t feel quite right on oral contraceptives. As with taking any medication, if a side effect doesn’t sit well with you, get off it and find something else. But overall, birth control pills are well-tolerated by most women.

There are a number of medical reasons why your doctor may not prescribe The Pill. Specifically, these are conditions that can make oral contraceptives dangerous. These include:

• uncontrolled high blood pressure

• prior clots in your legs or lungs

• prior stroke or heart attack

• severe liver failure or liver cancer

• gallbladder disease

• migraines with aura

• active breast cancer

• cigarette smoking with age over 35

If you have any of these, taking estrogen may not be a good choice for you – talk to your doctor about it.

THE PATCH

Hormones can also be delivered in other ways. Instead of taking a pill by mouth every day, an adhesive patch is applied to the skin weekly for three weeks, then nothing for the fourth week. Three weeks on, one week off. The hormone-free week triggers a period in the same way that “sugar pills” do. 

Because The Patch uses the same type of hormones as The Pill, their side effects are virtually the same. Additionally, The Patch can cause mild skin irritation under the adhesive.

Advantage: 96-99% effective. This improvement over birth control pills is likely due to not forgetting doses. Weekly dosing with a patch is typically easier than daily dosing with a pill. Women are instructed to pick a day of the week to be their “patch change day” – Sundays are common, so periods don’t start over the weekend.

Disadvantage: patches may occasionally detach. The adhesive is quite strong – only 1 in 50 will fall off during the week. Exercise, heavy sweating, swimming, and hot tubs don’t seem to affect adhesion. However, if it comes off within the first 24 hours of putting it on, it can be stuck back on where it was initially. If the patch falls off more than 24 hours after it was put on, it must be replaced with a new one, and this day of the week becomes the new patch change day. 

Disadvantage: patches may be visible. It’s typically applied to the buttock, abdomen, upper arms, or chest – somewhere discreet. Don’t put it on your breast, since the estrogen can cause increased tenderness in nearby estrogen-sensitive breast tissue. 

THE RING

Unlike patches, which must be changed weekly, a vaginal ring delivers hormones for three weeks straight. Each ring gets inserted high in the vaginal canal and stays there for 21 days, after which it’s removed for a week. A new ring goes in at the start of every cycle.

It’s 97% effective at preventing pregnancy during the year, with most failures related to incorrect usage.

Side effects are similar to other hormonal methods – primarily nausea and breast tenderness. It can occasionally cause vaginal irritation and increased discharge, but it’s usually mild.

Advantage: no pills to take, no patch to be seen. It’s invisible and relatively easy to use. Also, The Ring tends to be forgiving if it’s not inserted or removed exactly on time – not like forgetting your birth control pills for a couple of days.

Disadvantage: some women aren’t comfortable with an object in their vaginal canal, or with inserting/removing it.

PROGESTERONE INJECTION

Unlike the hormonal methods that operate on a monthly cycle, the progesterone injection suppresses ovulation and periods altogether for as long as you’re on it. Progesterone also makes mucus in the cervix thicker (more difficult for sperm to enter the uterus) and the uterine lining unfavorable for implantation. There’s no estrogen, just a long-acting progesterone that gets injected every three months. It’s 94% effective at preventing pregnancy.

Progesterone thins the uterine lining. This makes implantation of an embryo much less likely, if an egg somehow gets released and fertilized. However, it also makes breakthrough bleeding (“spotting”) a common side effect. 

For your first injection, it should be done within a week of your period starting. If you’re late getting a repeat injection, you should use another form of birth control beyond 14 weeks. Pregnancy is unlikely up to 18 weeks after injection, but it’s possible. Early repeat injection usually isn’t an issue.

A big advantage of the progesterone injection is that it has no estrogen. Some women can’t have estrogen for a number of reasons (see THE PILL section). Other advantages include:

• No regular period (excellent choice for those who normally have heavy menstrual bleeding)

• No pills, no patch, no ring, and no at-home maintenance

One of the biggest disadvantages is needing to go see your doctor every three months to have it administered. Such visits, while infrequent, can be a hassle to schedule and regularly attend.

Another disadvantage is that it can take a while to become fertile again. Although the progesterone injection is only supposed to last three months, it can take much longer to restore a regular cycle and ovulation. That means fertility might be delayed a year or more after your last injection.

There was some concern that bones can get brittle with years of progesterone injections, especially in teenagers whose bones are still developing. However, once the progesterone is discontinued, bone density tends to rebound back to normal. As well, the decrease in bone density is similar to what normally occurs naturally during pregnancy or breastfeeding.

Overall, progesterone injections work well if you don’t want to get pregnant for at least a couple years, and you don’t mind seeing the doctor every few months.

PROGESTERONE IMPLANT

Instead of an injection into your shoulder, a small plastic rod can be implanted under the skin, which slowly releases progesterone and prevents ovulation. It’s about the size and shape of a matchstick, but flexible. It usually gets placed just under the skin on the inside of the upper arm.

The insertion procedure is considerably less invasive than that of an IUD. A doctor numbs the area with freezing (local anesthetic), then the introducer pierces the skin and is gently burrowed under the surface. Once in all the way, the introducer is withdrawn, leaving the implant behind. The small hole is bandaged; no stitches needed. The whole procedure takes a few minutes and leaves a tiny scar when healed. 

Like IUDs, progesterone implants can be removed at any time. After your doctor makes a small incision, the implant is pulled out from under the skin. Again, no stitches needed, just a small bandage. Periods get lighter or disappear altogether.

Progesterone implants are supposed to be replaced every three years, but they may be effective for longer. 

The main disadvantage is their cost – considerably more than other methods. Also, because they’re relatively new, your doctor may not be familiar with it. 

SUMMARY

Hormonal contraception is readily accessible and relatively easy to use. However you choose to take the medication – pills, patch, ring, or injection – ovulation is prevented to reduce the chances of pregnancy considerably. Hormones are currently the most popular form of reversible birth control, but IUDs usage is quickly catching up.