I'm dry before my boyfriend and I are about to have sex. What can I do to fix this problem?
Vaginal dryness can have lots of different causes. Especially if you're having dryness all the time (even when you're not aroused or sexually active as well), you'll want to first check out the other things going on in your life and see if there's a cause there. Some medications and certain conditions (like hypothyroidism, vaginitis, or menopause) can lead to vaginal dryness. In terms of medications, some may inhibit vaginal lubrication or make it difficult for a woman to become aroused (thus decreasing lubrication when sexually active). Also, if you're not well hydrated it might impact your vagina just as it would any other part of your body, so you'll want to make sure you're drinking a good amount of water each day. During certain parts of your menstrual cycle, it's also not unusual to be drier.
If you're only feeling dry when you and your partner are sexually active, then there are some additional thing to consider. First, are you spending enough time on activities that relax and arouse you, engaging not just your vagina, but your whole vulva, including your clitoris, and the rest of your body? Often, we get in a big hurry and skip or rush the foreplay that allows your body the time it needs to relax and get really turned on. When we're in that arousal phase of sexual activity, the vagina is going to produce the slippery lubrication necessary to make sex (of any sort) comfortable. And that is not a process that we can really short change and expect it to work properly.
Also, are you only having sex when you really want to have sex? If you're not wanting sex or are just not into it, it's going to be harder for your body to relax and become aroused. Along with that, how are other things with you and your relationship? If we're not feeling great about ourselves (body worries, pregnancy or STI concerns, etc.) or have worries about our relationships (communication problems, etc.), it can often impact our ability to really relax and enjoy. Even if it's not something that you are conscious of right now, those sneaky little worries can impact things. So take a few moments and check out what's going on with you to see if there might be something there.
Finally, are you using extra condom-safe lubricant? If not, get yourself some! Lubricant is one of the best things ever. Now lube is not going to be a good substitute for taking time to become relaxed and aroused or addressing any other issues you might have going on. However, even if you are relaxed and aroused, lube is a good idea. If you're using condoms, it's important to remember that naturally produced lubrication does not tend to hold up well to contact with latex. (That's NOT a good reason to go without condoms since they are both good pregnancy protection and are the only method available that can protect you from STIs.) So adding extra condom-safe lubricant is going to help address that issue and will also have the added benefit of helping prevent condom breakage! Also, beyond a certain point (especially if you're engaging in penetrative activities that bring the lubrication out of the vagina) in any sexual activity, it's not unusual to become dry. Your body can only produce a certain amount of lubrication so fast. So no matter how much lubrication you produce naturally, extra lube is a good idea. It makes things much more comfortable and much smoother. Needing to use extra lube does not mean that there's anything wrong with you or that you (or your partner) are a failure in any way, it just means that you're normal.
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Lubricant (not diamonds) is a girl's best friend!