A comparison of maternal and paternal body mass index in early pregnancy

To determine the body mass index (BMI) and the body composition of fathers-to-be and to compare the findings with those of mothers-to-be during early pregnancy.

This was a descriptive and comparative study based at a large university teaching hospital. We enrolled men whose partner booked for antenatal care in the first trimester of pregnancy during July 2009. The height and weight of both parents-to-be were measured digitally, and BMI was calculated. The body compositions of the couple were analysed using bioelectrical impedance.

Of 167 fathers-to-be, 14% were obese (BMI > 29.9 kg/m2 ) compared with 16% of mothers-to-be (NS). However, 50% were overweight (BMI 25.0-29.9 kg/m(2) ) compared with 26% of mothers-to-be (P < 0.001). This may be explained, in part, because the men were on average two years older than the women, and in the men, BMI increased with age. The men had a lower overall fat percentage (P < 0.001), but their visceral fat was higher than in the women (P < 0.001).

Our findings show a high level of obesity in fathers-to-be, which has implications not only for the men themselves but also their families. We suggest that public health interventions directed at obesity during pregnancy should include both parents-to-be.