To do the deed or not? Leave them wanting more or get them hooked? It's a tough dilemma, but a new piece of research could help with the decision making.
Psychologists from the Israeli-based Interdisciplinary Centre Herzliya and the University of Rochester's Department of Clinical and Social Sciences in Psychology suggest that immediate sexual chemistry can help draw potential partners to each other.
"Sex may set the stage for deepening the emotional connection between strangers," says lead author of the study, Gurit Birnbaum, a social psychologist and associate professor of psychology at the IDC Herzliya.
"This holds true for both men and women. Sex motivates human beings to connect, regardless of gender."
During the experiment, researchers gathered men and women before subjecting them to four different interrelated studies. Psychologists analysed their behaviour towards each other.
Interestingly, 'emotional bonding' between two was fuelled by sexual desires.
"Sexual desire may play a causally important role in the development of relationships," continues Prof. Birnbaum.
"It's the magnetism that holds partners together long enough for an attachment bond to form."
For the first study, 36 women and 22 men were asked to lip-synch pre-recorded music. Participants were paired with an attractive, opposite-sex partner. Scientists then rated their desire towards the other person.
Next, they made 38 women and 42 guys slow dance with, again, an attractive, opposite-sex partner.
The team of researchers noted a link between "synchronisation" and whether there was a desire for the other person.
In the last two studies, the first including 42 women and 42 men, the second including 50 women and 50 men, scientists flashed an erotic, non-pornographic image for 30 milliseconds on a screen to see the reaction of the subjects.
Those who were turned on by the images were actually more "caring" and "helpful" in tasks.
The team of authors suggest this could be down to evolution, to guarantee reproduction.
"Throughout human history, parents' bonding greatly increased the children's survival chances," adds Birnbaum.