Worry over its effectiveness or mechanical preparations that halt the mounting excitement can add negative psychodynamics to intercourse that is remembered all too well the next time. With over 40 different birth control pills on the market, each one touting a unique formula boasting the best of all worlds, it is common for a woman to live in continuing PMS on the wrong pill. I've seen couples on the brink of divorce because the wife was on the wrong pill and the man was clueless about rolling with these hormonal punches. When testosterone falls in perimenopausal women, the libido crashes. There are estrogen hormones available which also include testosterone in the formulation for this problem.
Sexual dysfunction is a cause for decreased libido.
Sexual ignorance of a partner's needs can lead to anger and then hesitation the next time. Pain with intercourse is sure to nix the mood, and this should be worked up by the woman's gynecologist or the man's urologist. If a woman cannot react or if a man suffers from premature ejaculation, the sex act will end up being an exercise in frustration. There are sexual dysfunction clinicians available for instruction and treatment using clinical techniques. There are a plethora of self-help books about intimacy that can help educate the inexperienced couple.