Get Real! How Can I Be Sure My Birth Control Works?

curiousgirl asks:

have been on the pill for over 2 years, and have never missed a pill. I
just started my inactive pills on Sunday of this week, and had sex with
my boyfriend on Monday. He wore a condom but I am still concerned there
is a chance I might still get pregnant. Is it possible for this to
happen or am I safe?

Heather replies:

long as you take your pills as directed and on time, with the exception
of a few medications or herbs that can interact with the pill, you’re
as covered as you get.

I get questions like this a lot, so in the interest of making sure
you and everyone else understand your pill as best you can, let me
explain how the pill works and thus, why it works just the same during
the placebo period (the time you take or have the inactive pills) as it
does during the other three weeks of your pill cycle.

If you understand how your menstrual and fertility cycle works when you aren’t on oral contraceptives (and if you don’t, read this before reading further), it’s easier to understand how the pill works.

During a normal, unmodified fertility cycle, everything that happens
is first driven by the signals your brain, via the hypothalamus and
your pituitary gland, sends your reproductive system. Based on those
actions, the release of an egg by the ovary during a normal cycle also
releases hormones which direct the rest of the cycle, including the
type of vaginal secretions you’ll have for the best sperm mobility
during the fertile period.

When you menstruate, it’s because the egg released by the ovary
either wasn’t fertilized, or was fertilized but did not implant in the
uterus, so your endometrium which has built up from all of those
directives, to prepare for a fertilized egg implanting, then sloughs
itself off. That’s what your flow is during menses (which is also why
sometimes it has little globs in it, rather than just fluid).

When you take the pill, the synthetic hormones send a different set
of signals to your reproductive system entirely, so that you do not
ovulate — release that egg — so that your vaginal secretions become
and remain thicker (to make it tougher for sperm to get to an egg in
the case something went amiss there), and so that that endometrial
lining doesn’t build up as much (in the case that the other two modes
go awry, that would make it really tough for a fertilized egg to
implant). That’s three different ways to protect you from pregnancy,
and even just one of those ways is often enough.

The reason why you don’t have any extra risks during that placebo
week is because of all of the things the pill has done in the three
weeks prior, and which it will do once you start taking it again.
During that week, you don’t need pills because they’ve already
prevented ovulation and fertilization, so you couldn’t become pregnant
during that period of time, as without all those preceding signals to
be fertile, you can’t suddenly become fertile in that week.

Sometimes this is all more simply explained by saying that the pill
tricks your body into thinking it is already pregnant each cycle, which
is an accurate way to put it, since similar things do occur when a
woman is pregnant, and since you can’t become pregnant again once you
already are.

For more on how the pill works, one of my favorite explanations in visual format is on the PBS site about the pill, here. The Feminist Women’s Health Center also has a great general page about the pill, including loads of extra links.

While there are certainly downsides and risks with taking the pill,
one thing that isn’t a downside is how incredibly effective it is: in
perfect use, the pill is very close to 100% effective. When you combine
it with condom use — — which is always wise, since the pill offers so
STI protection — which are around 98% effective in perfect use, you have an awesome combined method that is beyond unlikely to fail.

Just be sure that you are taking your pills as directed — and if
you’ve lost your pill insert and need a reminder on what that means, check this out
— and on time, and it’s all good. Keep combining your pills with
condoms and I really can assure you that there is just no sound reason
to be worrying yourself about pregnancy. Obviously, no method, even a
combined one, is 100% effective, but right now, you’ve got as close as
it gets.

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  • invalid-0

    Did someone just refer to a fetus as “tissue” here?
    I just don’t get it… I have been indifferent about abortion most of my life. I didn’t know how often it happened or when it happened. As a teenager, since I come from a very conservative background, I would’ve considered it to avoid the “humiliation” within my religious community but at the same time I would’ve struggled with the “sin” aspect of it.
    A couple of decades later and considering myself to be liberal in most of my world views, and removing all “religious” bias from my thought process, I just don’t understand how a human life can be spoken of as if it were a cancerous growth.
    Our feelings or condition do not change the fact that there is a live being growing inside a pregnant woman. If you’ve been pregnant, you know that the relationship you had with your son/daughter started the moment you became pregnant. A live being capable of having a relationship and effect on someone else like this is as human as you or me that are typing on this blog.
    I truly believe that everything should be done to protect the life of a pregnant woman and if abortion is necessary I do believe it to be a choice a woman should be able to make with the appropriate medical advice.
    In any other situation, if it is believed a woman could go full term, then the life of the baby needs to be protected as yours or mine.
    I’ve never had a conversation with a pro-choice person but I really don’t understand what the argument for abortion could be… I keep reading post after post and there is no substance behind the arguments. Most of it sounds like there is a secondary argument behind the arguments and I don’t think that abortion is a subject we should use to push feminist agenda. Don’t get me wrong I agree that inequality has existed and will continue to plague our society a while longer but I hope one day people that fight for equal rights on this forum will take the fight to protect those that can’t even fight for themselves.
    Having said that, I also hope that “pro-life” proponents will have a more reasonable approach in this debate since every person is a world of their own and we have to understand that the situations in which these decisions are made are extremely complex and saturaded with emotions and information.
    Knowing that this post is to long for anyone to read and that I mainly did it to vent for myself, I tell myself one more thing; if you’ve witnessed birth and/or raised a child, you’re appreciation for life grows exponentially, both for the mother’s and the child. One does not exist without the other, cutting one from the other does not end it like you would a tumor, the child’s existence is always with the mother, forever. If your reasons for aborting are based on comfort and not life threatening conditions, think it over. Give yourself or someone else a chance to witness and experience the most beatiful gift the universe gave us. Remember, you can choose to be a part of the childs life or not. With an abortion you never give yourself that choice.

  • heather-corinna

    …is not mentioned even once in this piece.

    Nor is this about abortion or fetuses: this is a piece describing how oral contraceptives work to prevent pregnancy, therefore there is no fetus to discuss.

  • invalid-0

    no where in this post did i read the word tissue. are you speaking of some other post?
    you say you consider yourself liberal in most world views. yet, you say you’ve never had a conversation with a pro-choice person. interesting. do you have a different definition of liberal worldview than liberals have? it just seems odd to me that someone who is liberal could make it into adulthood having never had a conversation with someone who is pro-choice. as a liberal, i tend to have the closest personal relationships with others who are liberal.
    and, i think you’re missing a very important aspect of pro-choice. your comment speaks from opinion, belief, feelings…all yours, and that’s fine. but, you say that you can’t fathom any other reason for abortion than to protect the life of the mother. it’s a statement such as that which reminds me how important it is for anyone pro-choice to remain vigilent regarding a woman’s legal right to an abortion.
    just as you feel very strongly about the one and only situation when abortion is o.k., and just as you are completely sure that some deep type of relationship exists between a woman and a fertilized egg from the moment of conception – there are many who feel just as strongly that a fertilized egg, or zygote, or blastocyst is not “capable of having a relationship” with the woman.
    you claim that no one on this site can back up their arguments. i suspect that the truth is, you don’t agree with their arguments, therefore you consider them invalid. your entire comment was emotion, opinion, belief…how do you back up your arguments? do you even know or understand that implantation isn’t until the 3rd week? or that the embryonic period isn’t until the 4th week?
    pro-choice isn’t about what one individual feels is true about pregnancy, or when life begins. no one, NO ONE, knows when human life actually begins. you can have your opinion, your belief, and your theological theory…but, that should never supercede the female gender’s right to individually have their own opinion, and to excercise that opinion if they so choose.

  • heather-corinna

    (Betty, I think your responses here are simply to some other piece, or you’re thinking you’re continuing a conversation here which you’re having in another thread.  Again, this is a post about birth control, and you appear to be addressing someone when no one else is actually talking here.)