Try a different kind of lubricant maybe? Astroglide is a popular choice from what I've read online. You can get it from Lazada here: http://www.lazada.sg/astroglide-gel-personal-lubricant-4oz-3636419.html
Alternatively, if you are not breastfeeding (or you can pump and dump), having a glass of your favourite wine or cocktail can help. Alcohol causes the blood vessels to dilate and this will go a long way in helping your muscles down there to relax.
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