If both partners in a couple are overweight or obese, they are more likely to have to wait longer before successfully conceiving a child, according to new research published online in Europes leading reproductive medicine journal, Human Reproduction, today (Wednesday 7 March). 
Researchers in Denmark studied 47,835 Danish couples between 1996 and 2002 and found that if both partners were obese the chances of the couple having to wait for more than a year before the woman became pregnant were nearly three times higher (2.74) than for a normal weight couple. If both partners were overweight, the likelihood they would have to wait longer than a year was 1.4 times higher. 
Cecilia Ramlau-Hansen, who led the study, warned that if further research supported the findings of the study that too much weight could make couples less fertile, this would have major implications for population levels, particularly in parts of the world where obesity and low fertility were, or would become, more common.
If overweight and obesity actually is a cause of subfecundity, and if the obesity epidemic continues, this reduced capacity to reproduce could become a serious public health problem. Further research in this area is needed, she said.
Sub-fertility (or subfecundity) is normally defined as a waiting time to pregnancy of more than 12 months from the time a couple starts to have unprotected sex with an intention to conceive.
Earlier research has already shown that weight can affect fertility in both women and men, individually. However, this is the first study to look at the effect on fertility of overweight and obesity in couples. Ms Ramlau-Hansen, a doctoral student in the Department of Occupational Medicine, Aarhus University Hospital, Denmark, who is on a visiting scholarship to the University of California Los Angeles School of Public Health, USA, said: Since it is quite common to have couples where both partners are overwe
Contact: Emma Mason
European Society for Human Reproduction and Embryology