Knowledge of the growth of the neonatal conjunctival fornix and anterior orbit will aid development of neonatal prosthetic conformers and conjunctival sensors for oxygen determinations, as well as help define orbital malformation syndromes. These data are not available in any prospective series in the literature. The authors studied 55 premature and term neonates and determined horizontal and vertical dimensions of the conjunctival fornix and orbital margin and palpebral fissure width. Each of the ocular parameters had statistically significant correlation coefficients in relation to weight and gestational age (P less than 0.05). Linear regression analysis showed significant relationships which predict conjunctival fornix, orbital margin, and palpebral fissure dimensions from body weight (P less than 0.05). Statistically significant correlation coefficients and linear regression relationships were found for horizontal, but not vertical, diameter measurements of the conjunctival fornix in relation to orbital margin and palpebral fissure dimensions (P less than 0.01).