Things I Wish I’d Learned About Straight Sex in High School

Including: natural family planning can be as effective as birth control.

I always assumed that, after getting sex ed in some progressive, pro-feminist liberal school that I’d gotten a banging sex education. Add to that my volunteer time in planned parenthood, college level biology classes, many discussions and debates about female body issues with other feminists, and a safer sex education from the wider queer community, I figured I was a motherfucking pro when it came to knowing what was what about sex.

So, you can imagine my surprise when I picked up Taking Charge of Your Fertility, and realized holy shit, I have no idea how my vagina works.

In my defense, I think I actually did get a much better sexual education than your average American. Which… really makes me worry about our current level of sexual literacy.

While I don’t think the current liberal sex education actively propagated is great, it’s a hell of a lot better than the abstinence only education many conservatives promote. So, if you were the victim of an abstinence only sex education, feel free to check out the infographic on contraception I put at the bottom of this post. (I got from I thought it pretty good for readability and decent for accuracy, but obviously you should research any contraceptive method you’re interested in further.

So, to note, some of the places where things start to get questionably accurate is with the effectiveness rates of contraceptive methods. It’s not that the reported rates are inaccurate necessarily, it’s that they don’t fully expand on the conditions under which they are accurate.

For example, you may take a look at the stated effectiveness rating of condoms (82%-98% effective) and think, wow, that averages to a 90% effectiveness rating, that gives me a 1 in 10 chance of getting pregnant in a year. Doesn’t sound so good, does it? However, there’s a bunch of missing information here. The 82% effectiveness rate is a “typical use” case for people who use condoms, and part of typical use includes people don’t use condoms every time. To be clear, what is bringing down the average isn’t that the condoms aren’t working, but that people aren’t using them. If you use condoms every time you have sex, and put them on correctly (which isn’t hard, you just have to research how to do it) you can blast yourself into the 98% effectiveness range. You have control over how effective your condoms are. But, the way we present this information often makes it seem like it’s out of your control. We say condoms “are” 82–98% effective but that’s misleading. Condoms are 98% effective, but only if you actually use them.

The other thing this leaves out, is you usually know when condoms fail because you end up with a bunch of jizz in the vag. The usual way condoms fail is they break or slip and some come leaks out. If this happens, you have the option of using emergency contraception. This leads to more like a 99.8% effectiveness rating, or a 1 in 500 chance of getting pregnant. Quite a bit better than that 1 in 10 chance the infographic implies. (To see the effectiveness rating of other contraceptive combos, check this out.)

But, with a bit more knowledge, I think people can do ever better than that.

I is gunna explain to you the mechanics behind how babies happen. And, maybe you know this already — but, maybe like me, you thought you knew this already, but were actually missing some key pieces of information.

I’m assuming you know that babies grow inside a uterus, that they start growing in there after sperm has been deposited in the vagina, and 9 months after impregnation the baby is pushed out of the vagina. If you don’t know that, watch this video before you continue reading:

You should maybe watch this video even if you already know, cuz it is hilarious.

But, there’s a lot more detail than that — detail that I learned in Taking Charge of Your Fertility (I’m going to keep plugging that book, cuz 4 realz, that book revolutionized how I thought about my vag.) Trigger warning: for the rest of this explanation, I’m going to call people who ovulate “women” and people who ejaculate sperm “men” because I’m just not woke enough to explain the the details of impregnation in non-gendered language without sounding like a martian robot. Sorry.

The main piece of information that is often left out in conversations about contraception is that a woman isn’t always fertile. In fact, she is only fertile for about a week out of the month, whereas men are fertile all the time. Most people know that in order to get pregnant, a woman has to ovulate (or release an egg) that is fertilized by sperm. What many people don’t know, is that after a woman ovulates, the egg dies pretty quickly. Usually within 24 hours. So, if you have sex with a woman more than a day after she ovulates, she usually can’t get pregnant. There is usually only 1 day a month that a woman has a viable egg available to be fertilized.

What extends a woman’s fertility, is that before she ovulates, she produces a fluid that allows sperm to live in her body. Sperm can live in a woman’s body for up to 5 days, but only if her body is producing this special fluid. At other times of the month, sperm will die off much more quickly — usually within a few hours. Misunderstandings around this are pretty common.

People trying to get pregnant will sometimes have sex after ovulation, but this actually only gives you a very short window of fertility (1 day instead of 6 days.) Additionally, people trying to avoid pregnancy may assume that a woman isn’t fertile until she ovulates but this is definitely NOT true. If you want to get pregnant, you want to have sex the week before a woman ovulates, and if you want to avoid pregnancy, you want to have sex more than a week before a woman ovulates, or more than a few days after she’s ovulated.

Which begs the question: how can we tell when a woman is ovulating?

There are signs. I’ll give a brief overview, but anyone who wants to seriously know the signs either for pregnancy prevention or for pregnancy promotion should read more about it or take a class. To be clear, I will not be giving an in depth enough discussion to use as a reliable method of birth control. If you want to use fertility awareness for birth control, you will need to learn more about it.

The 3 main signs people tend to track are cervical fluid, cervical position, and temperature.

  1. Cervical fluid is the fluid that comes through a woman’s cervix and out of her vagina. It changes consistency throughout a woman’s menstrual cycle. When it is clear and the constancy of egg whites is when a woman is most fertile/sperm will best be able to live in her body. This is also why the discharge on a women’s panties will look different at different times in her cycle.
  2. Cervical position can be tracked by a woman putting her fingers in her vagina and feeling her cervix. If it’s low and firm, it means she’s less fertile, if it’s high and soft, it means she’s more fertile.
  3. After a woman ovulates, her “basil body temperature” will be slightly higher. Basil body temperature must be taken first thing in the morning before a woman gets out of bed. If a woman takes her temperature every day, she can usually tell when she’s ovulated because there will be a slight increase in temperature afterward. She can even tell if she got pregnant since pregnancy is correlated with an additional, secondary rise in temperature a few days later.

Some fertility awareness birth control methods only use one of these, but the most accurate method (the sympto-thermal method described in Taking Charge of Your Fertility) uses all three.

Here is an example of fertility chart from typical cycles

This is a chart from a woman trying to get pregnant, but is very similar to the chart for women avoiding pregnancy (just, the days she has sex will vary.) The green zone is the zone when the woman was most fertile, and the dark green line on day 13 indicates that was the day she was most fertile. Day 14 is the day she ovulated (vertical purple line) and note how all the temperatures after that day are uniformly higher than the temperatures taken before. This chart tracks many things, but additional things to look include are C Fluid (meaning cervical fluid) — note how the days of most cervical fluid correlate with her increased fertility — and additionally, Cerv Softness and Cerv High/Med/Low. These also correlated with fertility giving a woman reassurance that she’s reading the signs correctly.

This method of ovulation tracking isn’t widely propagated. You’ll note that on the contraceptive method chart at the bottom of this post that all “fertility awareness methods” are correlated with the “rhythm method.” This is common categorization, but it is also incorrect. The rhythm method is an out-dated and fairly ineffective birth control method that is based on simply using the calendar to figure out the best days to have sex without taking into account any of the other signs (body temperature, cervical fluid or cervical position.) It’s a bad method because women’s periods are often irregular, and it’s very hard to correctly predict the day of ovulation without tracking these signs.

The bullshit rhythm method, along with religious write ups on natural family planning that include things like “if God decides you should have another child, just embrace it as part of his plan” have likely contributed to the unpopularity of natural family planning. However, a recent study in Germany found that women using natural family planning perfectly had a pregnancy rate of 0.4%, which is on par with the the effectiveness ratings of the contraceptive pill. Now, I’m not saying everyone should go out and use the sympto-thermal method. Frankly, it’s a pain in the ass to take your temperature every morning.

But, you could combine some degree of fertility awareness with other barrier methods. For example, if you chose only to chart your cervical fluid and combined it with condoms and the morning after pill, you’d have a method of birth control far more effective than — say — the pill alone. And even if most people choose not to use any of this information in their everyday life, it seems like highly relevant information for anyone who might want kids someday. Which leads me to be really pissed off that they don’t teach it in schools, considering all the other useless info they teach.

For people having difficulty conceiving, there’s a whole bunch of info can be useful. Women can tell if they’re not ovulating, they can tell if they’re not producing the right fluid for sperm to live in their body, and they can tell if they are in fact getting pregnant but miscarrying early so it looks like a period. Many of these problems have solutions, but they have different solutions. There’s a lot of information a woman can gather before even visiting a fertility doctor that will increase her chances of conceiving.

I suppose when it comes to contraception, part of what really gets to me is how much those educating us strip us of our own agency. Many people are denied any reasonable sexual education with abstinence-only curriculum which — as far as I know — is still in place in many states. Abstinence only education is a fucking travesty; even if people choose to be abstinent for religious reasons, this is a choice they must make for themselves. They deserve information on how contraception works for if, and when, they need it. And, even those of us who received a “good” education are deprived of much basic information regarding fertility, and the role our own agency can play in shaping our reproductive outcomes.

Effectively, we are educated to indulge in a sort of learned helplessness, to rely on others to make the best decisions for us. We’re often not given the full information, because we’re assumed to be too stupid to use it. Using our own agency to improve our situation are often actively discouraged because it’s difficult to fit into the medical machine. But, it doesn’t have to be this way. The information is out there, if you look for it.

Infographic from