A new chart to monitor maternal weight gain during pregnancy is presented. The chart is based on the adequacy of maternal weight for height, as suggested by a modified table of weight for average frame size, and the data were derived from a low-income racially-mixed population living in New York City. A nomogram accompanies the chart and is used to calculate values of percentage of "standard weight" at various gestational ages. The chart establishes a desirable weight near term which is equivalent to 120 percent of "standard weight" for women with a pre-pregnancy weight equal to or lower than 100 percent of "standard weight". For women with pre-pregnancy weight above 100% of "standard weight" the desirable weight near term varies according to the initial weight but includes a minimal weight gain of 7 kg for women with pre-pregnancy weight over 120% of standard. Women who attained or exceeded body weight near term equivalent to 120 percent of "standard weight" in low income populations in the US and Chile delivered infants with significantly higher mean birth weight than those from mothers who did not meet this goal.