A woman’s libido is complicated. Getting in the mood doesn’t just hinge on one organ—there are so many emotional and mental factors that can influence how feisty you feel, which makes it easy for your sex drive to fluctuate. You’re not always going to be jumping to hit the sheets, and that’s totally normal.

If you’re someone who is typically raring and ready to go, it’s frustrating when that feeling suddenly goes missing. But it’s very normal for women to experience problems with sexual desire at some point, Kate Thomas, Ph.D., a director of clinical services in the sexual behaviors consultation unit at the Johns Hopkins Hospital, tells SELF. And for every woman who speaks up about it, there’s likely to be a handful more who have the same experience but don’t seek help.

If you’ve noticed your sex drive is lower than normal and can’t figure out why, here are some things that could be causing the change.

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1. Something is missing in your relationship.

“Women in long term relationships lose their sex drive more readily than men,” Thomas says. There’s a number of different theories as to why this happens, but Thomas suggests that because emotion plays a bigger role in sex drive for women than men, it’s more likely sex drive will go away if a connection is lost or feels strained. “For women, if the emotional connection is lost in a relationship, that can color how much sexual desire there is,” Thomas says. 

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2. You’re aging (of course you are).

Unfortunately, you can’t really stop this from happening. As we age and our hormonal balances change, so does sex drive, Thomas says. That’s because testosterone levels change throughout life, peaking in our 20s, and then decreasing slowly as we age. The ovaries continue to produce some testosterone even after estrogen drops rapidly in menopause, but low estrogen comes with its own side effects that make sex unenjoyable (like vaginal dryness and pain with intercourse) and therefore, can dampen your drive.

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3. You switched up your birth control.

Change in libido is a known side effect of hormonal birth control. Even if you’ve been on one pill and never had issues, switching to a new one with different levels of progesterone could have an impact. Talk to your ob/gyn if you’ve noticed a change in your libido that coincides with a new form of birth control. Thompson suggests asking about non-hormonal options, like the ParaGard IUD, that can prevent pregnancy without messing with your hormones.

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4. You’re taking a new medication that inhibits orgasm.

It’s not just birth control that can put your sex drive on the fritz. SSRIs prescribed for depression are very well known to dull desire, which Thomas explains can be because they can make it more difficult to orgasm.

“An orgasm is important for women’s desire,” she says. “If you don’t have spontaneous desire but want to be sexual and know you’re going to enjoy it, you’re ready to do it. In a sense, the desire becomes amplified. But if it’s always a disappointing experience, you won’t want to do it.”

Other medications like those for hypertension diminish orgasm as well. Opiates are notorious for making orgasm difficult, and the effects can happen even with short term use. “But desire will go away completely if you’re on them more chronically, and of course chronic pain itself can cause decreased desire.”

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5. You don’t feel as desired by your partner as you used to.

Another theory for why LTRs smother the fire is that many women get off to knowing they’re wanted. Knowing your partner desires you makes you feel sexy and confident as hell, and therefore, turns you on. Makes sense. “If you read female erotica, just about all of it has this quality, where this person wants her.

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In “Fifty Shades Of Grey,” it’s more about the fact that Christian Grey wants her, when he could have anyone,” explains Thomas.

In a new relationship, there’s this fuel where your partner makes it known they want you. In an LTR, you may feel loved and cared for, but that I-need-to-have-you-right-now feeling may have faded and taken your desire along with it. Having an open conversation with your partner about how you’re feeling and coming up with new ways to spice things up is the best way to reignite that desire and get out of a sexual rut.