Growth and development of twins compared with singletons at ages one and four years.

OBJECTIVE To compare the growth and development of twins with normal control singletons and also with matched 'high risk' singletons, at one and four years of age. DESIGN A four year prospective follow up study. SETTING High risk clinic (HRC) of a referral hospital. SUBJECTS Twin pairs enrolled in the HRC; normal full term singleton controls; and high risk "matched" singletons enrolled in the HRC. METHODS The height, weight and head circumference was measured at one and four years. Development was assessed at 1 year using the Bayley Scales of Infant Development. At 4 years, the intelligence quotient was determined by the Stanford Binet Intelligence Scale. RESULTS Forty two twins and an equal number of controls were assessed at one year. All the twins weighed less than 2 kg at birth. They lagged behind in all three parameters of growth, namely, height, weight and head circumference. AT 4 years, 24 twins came for follow up. Although, they had caught up for head circumference, they lagged behind in height and weight, particularly the group of fourteen SGA twins. The growth parameters of LBW twins and LBW matched singletons did not show any significant difference. At one year, the development of twins was within normal limits although the motor quotients were significantly lower than that of controls. At 4 years, the intelligence quotients of twins were well within normal limits. CONCLUSIONS Twins were lighter and shorter than controls at four years, particularly the SGA twins. The growth parameters of LBW twins and LBW matched singletons showed no significant difference. The intelligence of twins was normal at four years.