Intrauterine growth pattern by the tendency to repeat small-for-gestational-age births in successive pregnancies.

Abstract

Background: Fetuses of women who repeat small-for-gestational-age births in successive pregnancies may have a different intrauterine growth pattern than SGA birth of non-repeater mothers. Also repeated SGA births may grow differently depending on whether the tendency to repeat is due to some external factors such as cigarette smoking ("false repeaters") or due to genetic or intrinsic factors ("true repeaters").

Material and methods: Fetal growth were compared in a "nested case-control" study within a longitudinal (cohort) study, comparing three types of SGA births, 23 of "true repeater" mothers, 46 of "false repeater" mothers and 65 of non-repeater mothers, and these were compared with 1017 non-SGA births. Fetal growth was compared using a regression analysis based on repeated measurements (four for each woman).

Results: For mean abdominal diameter the "true repeater" SGA births grew more slowly towards the end of pregnancy. However, the growth curves show only minor differences between the three types of SGA births, but the patterns are grossly different from the growth of non-SGA births (controls).

Conclusion: The intrauterine growth retardation starts early in pregnancy, and is not strikingly different between births of repeater and non-repeater mothers.