About Sex
You will probably be told to hold off having sex until after your six-week checkup. There is nothing magical about six weeks, really. If you had a vaginal delivery, you can safely have intercourse any time after all bleeding stops (bleeding indicates that your cervix is still open and bacteria could easily invade). This usually takes two or three weeks, but it's more important to wait until you actually want to have sex. And you may want to, especially if you've had an easy birth and a baby who sleeps a lot.
Probably, though, you won't want to. Your vaginal area may still be tender, your scar from any episiotomy or tearing may be sensitive. You might feel just fine physically, but the memory of how much the birth hurt may still make you cringe. Your body may feel odd when you are touched, in part because the hormonal effects of breastfeeding change your skin (this can be remedied with lotion or massage oil), and also because you're being touched so much by your baby you just can't take any more.
Starting Over with Sex
Sometime after getting the six-week go-ahead (possibly way after, research shows, if your baby wakes frequently at night) you may find yourself having fond memories of sex, fond enough to contemplate having it again in spite of your exhaustion. Or, more likely, you may want to try it just once to reassure yourself that everything still works, and then have no interest again for months. When you hit this point, think Astroglide.
You will need a lubricant because your vaginal walls postpartum are thinner and produce less natural lubrication thanks to the dramatic drop in estrogen. Gel lubricants are goopy and will remind you of getting a pelvic exam, but Astroglide is barely thicker than water, nearly invisible, and works like magic.
You may find articles that say all you need to solve the lubrication problem is a little extra time for foreplay, starting with dinner out and a bottle of wine. If you're nursing, you really shouldn't have more than a little bit of wine and, in the brief hours your baby gives you between feedings and considering how tired you probably are, how realistic is dedicating hours to foreplay? Go for the lubricant.
If sex hurts, a different position may help. Consider one that puts the least amount of pressure on the scar where you tore or had an episiotomy. That area, typically at the base of the vagina, will become less sensitive eventually, but it may take a year or more. Find a position (use pillows if you have to) that angles your partner away from the scar. If you have very sharp pain, use a mirror to check your scar for a black line like a splinter — you may have a stitch that didn't dissolve and it will need to be removed.
After a C-section the biggest concern is the abdominal scar; any position that puts pressure on it is out.
Talk to you health care provider if dryness is a problem even with the Astroglide. She may recommend an estrogen cream that will make the vaginal tissue softer and more lubricated.
Milk Gets in Your Eyes
Sex can make your milk spray because oxytocin, the hormone that triggers the let-down reflex, is released when you have an orgasm. This can, as you might imagine, be distracting. It's at least good for a laugh, but might make you lose any romantic focus. The best way to handle it, if you don't like cold wet sheets, is to wear a sleep bra with nursing pads. Also, try to feed the baby shortly beforehand (though you may leak anyway).
The optimal time window may take a while for you to figure out. If your baby's been fed recently, he'll be more likely to give you some free time and, if you're nursing, your breasts will be less likely to leak.
Get to Know Yourself Again
Of course, leaking milk effectively makes your breasts off-limits. To be honest, many women find that they can't stand to have their breasts or nipples touched in the first few postpartum months. Your new shape may be a turn-on for your partner, but your bigger breasts may not feel erotic at all to you. This can be frustrating for both of you. The answer, like with any other problem, is to be honest about what's a turn-on and what's not.
There may be other parts of your body that you used to like to have touched and suddenly don't. It might be your stomach — a reminder of how much work you have ahead to tighten it back up again. All these new rules about what can and can't be touched will probably baffle your partner, but your body has been through some huge changes. Why would you expect everything to feel the same?
Timing Is Everything
Complicating the whole sex thing even further is the probability that when you have an orgasm, or are about to, your baby will wake up. Anticipating his cry can ruin the most romantic moment. If you can get away for a few hours, do so.
Don't worry about it if you really, really don't feel like sex, but don't entirely forget about it. Remember there are other ways to be intimate besides sexual intercourse. Start off slow, just touching and cuddling with each other, even if it doesn't lead to intercourse. The goal is not just physical intimacy, but emotional intimacy with your partner. If you continue to have an aversion to sex, after a few months, talk to your healthcare provider to make sure that there are no physical issues. Be honest with your provider about any emotional problems you now feel about having sex.

