While technically, UTIs are caused by invasive bacteria like E. coli, hormones are able to change just how likely you are to get a urine infection.
Depending on our time of the month, our immune system function changes, affecting how likely we are to get sick. For example, some studies show that during ovulation women have a more robust immune system that can better fight off infection.
While this is a natural fluctuation that has evolved over millennia, yet we can immediately change this rhythm when we take hormone contraceptives. Many of us have been on hormonal contraceptives for years or even decades to prevent pregnancy or to get rid of severe or debilitating menstrual pain.
We’ve already talked about how contraceptives like condoms and IUDs can affect your UTI risk. But what about the Pill you take every day or the Depo-Provera shot you get every 3 months? Could that be driving your UTI risk? Let’s delve deeper.
Hormonal Contraceptives Trick Your Body
Are you aware of how oral and injectable contraceptives work? They are hormone contraceptives, which means that they are derived from the natural “female” hormones progesterone and estrogen.
A “progestin” is a progesterone derivative. These hormones control the female cycle from puberty through menopause.
Essentially, these “look-alike” contraceptives work at three different levels to prevent you from getting pregnant or reduce your painful period symptoms:
- Stop you from ovulating, which means you don’t release an egg during your cycle. No egg means no chance of it getting fertilized by any sperm swimming around.
- Increase the cervical mucus. This mucus makes it much more difficult for anything, including sperm, to get to the uterus. Your body naturally does this AFTER you are already pregnant, so a single egg doesn’t get fertilized by another sperm.
- Thin the lining of the endometrium (the inside of your uterus). This prevents any superhuman egg-sperm combination that made it past the first two steps from being able to set up residence in your uterus and grow into a baby. This is more a theoretical effect as some studies show that contraceptives are not very good at this step.
Basically, contraceptives have a similar structure to your natural hormones and “trick” your body into thinking you are already pregnant.
While these three methods of protection are great at keeping you pregnancy free, as they say, “nothing in life is free.”
Which Hormones Does Your Pill Have?
Oral contraceptive (OC) pills have a host of side-effects that you need to know. Unfortunately, many of the UTI associated side effects are not discussed when you get your prescription.
It’s important to note, that different contraceptives types could have different effects on different women. This is because OC can’t perfectly mimic the fluctuation in our cycles and they aren’t exact copies, so they interact differently with our bodies than progesterone and estrogen.
Depending on the type of OC, the pill can either increase or decrease the effects of natural hormones in different parts of your body.
- For example, progesterone causes changes in your mood, bone density, thinking, bloating and thyroid to name a few. It is no wonder that contraceptives can have a wide range of side effects.
- Combined oral contraceptive pills (OCPs), meaning that they have both estrogen and progestins, are the most common type of pill.
- There are also low dose progestin-only “mini-pill” as well. The mini pill is the better choice for women with certain health conditions like blood clots and is often prescribed to women who are breastfeeding.
- On the other hand, injectable or intrauterine devices (when they are hormonal) usually only contain progestins.
So, can hormonal contraceptives wreak havoc on your risk of future UTIs? Probably. Here is why.
#1: If Your Hormonal Contraceptive Causes UTI, Check Your Stress Hormones
Progestins directly affect your body’s stress levels because they bind to the glucocorticoid receptor. This is the same way that cortisol (the stress hormone) is able to achieve our “flight or fight” response.
We all know that prolonged stress is bad for us and the same holds true if our hormones are increasing our stress levels.
Studies show that more activity in this receptor decreases bone density, immune function and glucose insensitivity, which is one of the earliest steps leading to diabetes.
Depo-Provera, a contraceptive shot you get every 3 months, targets the glucocorticoid receptor. In fact, one study showed that the active medication in Depo-Provera is twice as effective as cortisol at turning “on” the glucocorticoid receptor. This means that the Depo shot could trick your body into thinking you are really stressed out.
In this way, Depo-Provera can decrease your immune function, and over time, make you more susceptible to certain infections like UTIs.
On the other hand, the progestins in the Pill have little or no effect on the glucocorticoid receptor, which is likely a big reason that OCPs are less often associated with vaginal infections. More research studies are definitely needed to figure this out.
There is increasing evidence that Depo-Provera and some oral contraceptives actually increase a woman’s risk of getting HIV and other STIs. This is obviously concerning as many women at risk for HIV use contraceptives. In addition, although UTIs are rarely caused by viruses, some STIs, like chlamydia, can actually cause urine infections.
It also is not too far a leap to realize that if contraceptives increase our risks for infections like HIV and STIs, they likely can increase our risk for UTIs. This is supported by the fact that there is a high rate of UTIs in women who have STIs.
#2: OC & UTI? Check For Vaginal Inflammation
Studies show again and again that hormone contraceptives are not the same as our natural hormones and can in some cases even have the exact opposite effects than the hormones they are simulating.
For example, the active ingredient in Depo-Provera shots (medroxyprogesterone) and many of the OCPs and Norplant (levonorgestrel) actually increases inflammation in vaginal cells.
One study looked at women who used either of these two medications for contraception compared to women who were not on any hormonal contraceptives. They found that women on contraceptives had different types and amounts of inflammatory cells in their vaginal wall.
This means that women on contraceptives may not be as well prepared to fight off infection-causing bacteria that make it to the vagina.
For example, some studies show that women on progestin contraceptive had more of a certain type of immune cell called Langerhans cells. These cells can be “tricked” by viruses to actually increase the risk of infection. Other research shows that progestins decrease the activity of other immune cells.
#3: The Pill Could Lead to Thinner Vaginal Lining That Linked to UTIs
Some studies show that certain contraceptive hormones can damage the vagina by thinning its inner lining. This is similar to what happens in women going through menopause.
We already know that post-menopausal women are more likely to have UTIs. One reason for this is that the thinned vaginal wall is not as effective as protecting us from infections. That’s because a thinned vaginal wall is more likely to be damaged during intercourse or even regular daily activity.
Interestingly, at least in animal studies, vaginal estrogen can decrease this risk. This is the same treatment used for women dealing with the side effects of menopause.
For example, some studies show that vaginal estrogen decreased the risk of transmission of HIV in women on contraceptive pills. Studies show that the Pill causes less inflammation than IUDs and does not damage the lining of your cervix.
#4: Hormonal Contraceptives Change Vaginal Flora
Luckily, the news is not all bad. One study looking at women who used combined OCP for up to one year showed that they had less chance of getting bacterial vaginosis (BV).
Bacterial vaginosis is one of the most common causes of vaginal infections and it occurs when the good bacteria (lactobacilli) in your vagina are overwhelmed by the disease-causing bacteria.
We know that women who have BV are much more likely to get UTIs, so this study suggests that the Pill may actually be a pretty good choice for women with UTIs.
Women who have taken combined OCPs– compared to women who used condoms or had an IUDs- also had higher levels of peroxide producing lactobacilli. These are the good bacteria that are really effective at keeping the vagina healthy, another sign that these contraceptives are good at combating UTIs.
These benefits also held true for women who used intramuscular shots or subcutaneous implants (like Depo-Provera or Norplant). They were less likely to have bacterial vaginosis for up to a year after starting the medicine. However, they were not more likely to have the more beneficial type of lactobacilli.
Although it seems that the Pill is the clear winner, they still can affect the vaginal flora for worse.
However, a study showed that OCP users were about two times more likely to have recurrent vaginal yeast infections than women who did not use a hormonal contraceptive.
In contrast, IUD users were four times more likely to get a yeast infection. Like BV, vaginal yeast infections can contribute to your risk of UTIs.
Which Hormonal Contraceptive if Prone to UTIs?
Overall, women on multiple types of hormonal contraception are more likely to have vaginal infections, STIs and may even increase their risk of HIV. As we know, all of these infections can increase our risk of getting a UTI.
For now, it seems as though if you must be on an oral contraceptive, combined OCPs are the least likely to cause UTIs or vaginal infections. However, they probably still increase your risk compared to not using contraceptives at all.
As we have discussed before, vaginal health may be key to preventing UTIs for women, so it is important to know how any medication can affect the nether regions.
It’s also important to know the type of hormones in your OCP or injectable as they are definitely not all the same.
Since there are many different contraceptives out there, you need to be aware of how your particular brand affects your body. You can touch base with your doctor and ask if your OCP or injection may increase your personal risk of getting UTIs.Read Next:
What’s your experience? Have you noticed a difference in the number of UTIs since changing your birth control method?
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