Twin growth: Initial deficit, recovery, and trends in concordance from birth to nine years

Abstract

Height and weight measurements for a large sample of twins from birth to nine years were used to construct growth curves for this period. Compared to singletons, twins were substantially smaller at birth, particularly for weight (30% deficit), but the latter showed a dramatic recovery in the first 3 months, then smaller increments until finally reaching the singleton norms at 8 years. Height, while less depressed at birth (17% deficit), was also slower to recover during the first year, then moved in comparable increments with weight until reaching parity with singletons. Prenatal influences on birth size were largely dissipated as each twin converged on his/her genetic growth curve. Monozygotic twins became progressively more concordant with age (R = 0.94 for height), while dizygotic twins became less concordant (R = 0.49). Ten monozygotic pairs with large birth-weight differences (greater than 750 g) were examined at 6 years; the smaller twin was still significantly lighter (P less than 0.01), marginally shorter (P less than 0.10), but not significantly lower in IQ. The results suggested a high degree of buffering for intelligence against the effects of nutritional deficit in the prenatal period. Some factors in addition to placental anastomosis are suggested as a possible basis for long-term size differences in monozygotic pairs.

Body Size of Twins Compared with Siblings and the General Population: From Birth to Late Adolescence

“…In accordance with previous literature birth length was less reduced than birth weight when compared with singletons. 11,12 It is known from these studies that the fall off in birth length starts later in pregnancy and is of smaller magnitude than the fall off in birth weight. This may explain our findings that the deficit in height disappeared among 4-year-old twins, but they were still somewhat underweight.…”

“…10 Several studies have shown that the differences in body size between twins and singletons at birth disappeared during childhood, but in a few studies differences remained until adulthood. [11][12][13][14][15] The Louisville Twin Study concluded that the effects of prenatal growth suppression on weight and height appeared to be fully dissipated by age 8, 11 and a Finnish study among 17-year-old twins reported that twins were as tall as singletons, but that boy twins were still leaner. 13 We found in a previous study that at the age of 5 years, female twins were as tall as singleton children, whereas male twins were still somewhat shorter than children in the general population.…”

Multiple Births in Sub-Saharan Africa: Epidemiology, Postnatal Survival, and Growth Pattern

“…Many studies concur on the existence of compensatory growth in twins but contradict on the age at which the full recovery is achieved. A longitudinal study conducted in the United States concluded that compared to singletons, twins were substantially smaller and shorter at birth, but later showed a recovery until they ultimately achieve the singleton norms at eight years (Wilson, 1979). A study in Japan also found the size deficit was fully recovered over the first six years of age (Ooki & Asaka, 1993).…”

Analysis of multiple births in Japan IV. Body weight of 4,317 twin pairs at one year of age

“…It was also indicated that percent deviation within the pair was lower in like-sexed than in unlike-sexed twins, in particular at the age one year, where estimated frequency below the median of percent deviation was markedly higher in MZ (63.4~) than in DZ twins (28.2~) (Table 6), suggesting an effect of genotype on the gain of weight. Wilson (1979) has reported longitudinal study on the weight of twins, in which within-pair correlation at birth was 0.63, 0.68 and 0.64 for MZ, same-sexed DZ and opposite-sexed DZ twins, respectively. At one year of age, it was 0.88, 0.55 and 0.37, respectively.…”

“…It was indicated that the lower the sum of weight of twins at birth, the higher the growth rate at one year of age (Table 10). Wilson (1979) reported that the weight deficit of twins at birth showed dramatic recovery in the first three months, then smaller subsequent reductions until it was fully offset by eight years. He also mentioned that the lightest twins (10th centile), who were the most sharply depressed in birth weight, nevertheless made the largest postnatal gain.…”