Pregnancy weight gain in Iranian women attending a cross-sectional study of public health centres in Rasht.

OBJECTIVE: to investigate pregnancy weight gain in a group of Iranian women who regularly attended urban public health centres for prenatal care in Rasht, Iran.

DESIGN: an existing data study analysing routinely collected health-centre data.

SETTING: six randomly selected health centres in urban areas in Rasht.

PARTICIPANTS: 704 pregnant women aged 26.1+/-5.6 years who regularly attended health centres for prenatal care and delivered between June 2002 and May 2003.

MEASUREMENTS: data on pre-pregnancy weight, height, total pregnancy weight gain, mother's age, smoking habit, parity, baby birth weight, mother's education and working status were extracted from the health records. The women were categorised based on their pre-pregnancy body mass index (BMI) as 'underweight', 'normal weight' and 'overweight' (and obese). Participants were also grouped on the basis of their years of schooling as 'low', 'intermediate' and 'high-education'; pregnancy weight gain was compared between groups and with recommended ranges.

FINDINGS: weight gain below the lower cut-off recommended by the Institute of Medicine (IOM) were 64% and 67% in underweight and normal weight women, respectively. Baby birth weight and chance of low birth weight were negatively related to pre-pregnancy BMI and pregnancy weight gain. After controlling for the differences in parity, pre-pregnancy BMI, mothers' working status and age, highly educated women (>12 years schooling) gained more weight during pregnancy than women with an intermediate (5-12 years schooling) or lower level of education (< 5 years schooling).

CONCLUSION: this study indicated that a considerable proportion of underweight and normal weight women had pregnancy weight gain below the lower cut off recommended by the IOM. These findings suggest that, in terms of pregnancy weight gain, prenatal care in the present health system is unsatisfactory. It would seem that a more effective nutritional education programme, especially for less educated pregnant women, is necessary.