Great sex is all about spontaneity and exploration—assuming, of course, you have her consent—but there are a few parts of her body you shouldn’t touch willy-nilly.

Here are four such spots you’re better off avoiding. (For explicit instructions on where and how you should touch her, check out How to Pleasure a Woman, the ultimate sex manual from the editors of Men’?s Health.)

Her Cervix

If you reach her cervix during sex, recognize that something is wrong. Remember, this is the narrow canal that connects the vagina to the uterus—where babies grow. That isn’t a place you want to go, so don’t knock on the door.

For starters, it’s painful for her to have something rammed against her cervix, and it could be a sign that you need to shift for a position with shallower penetration. But it could also mean that she isn’t warmed up enough. Her uterus will actually “lift” upwards when she’s sexually aroused, making her vaginal cavity a few inches deeper than when she isn’t turned on.

So don’t skimp on foreplay, and don’t service her cervix.

The Head Of Her Clitoris

This might seem counter intuitive, but the clitoris—which is full of super sensitive nerve endings—can sometimes feel too intense when it’s stimulated directly. Touching the clitoris head-on, especially if she’s really aroused, can feel too severe.

Think about that feeling when you gulp an ice-cold beverage and your teeth start to tingle—it’s just not pleasant. Instead, try going for the shaft of her clitoris or rubbing circles around it, which will engage the nerve endings without overstimulating her.

We won’t tell you to never touch her there, but it’s worth checking in with your partner to see if she has a sensitive C-spot.

Her Feet

Especially if she’s sporting socks. A study from Johns Hopkins University showed that wearing socks in the sack can increase orgasm potential, for both men and women.

One potential reason: In order to orgasm, women need to be totally relaxed and anxiety-free, and cold feet can interfere with their ability to really get into sex.

Though we usually recommend knocking her socks off, leave them on this time.

Her Anus

Unless you’re all lubed-up, that is. Anal play can take plenty of warming up, but even when she’s totally aroused and ready to get it on, nothing should go in there without a generous helping of lubricant. The anal opening is small enough that even a finger can feel uncomfortable.

While you’ve got the KY bottle handy, you should probably go ahead and use it for all other acts. A study from the Journal of Sexual Medicine found that women rate their sexual satisfaction much higher when lube is involved.