Remember that oxytocin, while released during an orgasm, also needs to be released in order to have an orgasm. At the moment of orgasm adrenaline is also released. Labor is really like one big orgasm, if things are going well you are releasing oxytocin all the time and when you reach the fetal ejection point you will release a flood of adrenaline as well. This is why women just before the moment of birth will stand up or become agitated or start shaking.
So, in order to have a labor "orgasm" you have to have similar conditions as having an orgasm otherwise. You need to feel safe, warm, unobserved and the lights should be kept to a minimum. Some women have an easier time in different conditions because their inhibition levels are lower than some. Feeding your need to have privacy will increase your hormone levels and increase your chances of a safe birth. So, even if it seems totally unreasonable, make sure you feel comfortable and uninhibited. You are trying to have an orgasm in the grand sense. And while birth can be pleasurable for some women, I am not using orgasm in that sense, I am referring to the hormones only.