Foetal growth velocities in twin pregnancies

Abstract

A r etr ospecti ve l ongi tudi nal study w as per for med to quanti fy foetal gr ow th vel oci ti es i n tw i n pr egnanci es and to deter mi ne the effect of var i abl es speci fi c to tw i n pr egnanci es on gr ow th vel oci ty. Foetal gr ow th vel oci ty standar d devi ati on (Z) scor es w er e cal cul ated fr om ser i al ul tr asound data usi ng publ i shed si ngl eton r efer ence data for 131 consecuti ve sets of tw i ns fr om 30 to 37 w eek s' gestati on. Compar ed w i th l ow -r i sk pr egnanci es, the tw i n foetal abdomi nal ar ea gr ow th vel oci ty Z scor es w er e si gni fi cantl y r educed fr om 30 to 37 w eek s and bi par i etal di ameter gr ow th vel oci ty Z scor es w er e al so si gni fi cantl y l ow er, fr om 30 to 33 w eek s. A mongst the tw i n pai r s ther e w er e no si gni fi cant di ffer ences i n Z scor es w i th r espect to chor i oni ci ty, foetal sex, bi r th or der to w hether del i ver y w as pr ematur e or ter m. Thi s r etr ospecti ve study has demonstr ated that tw i n foetal gr ow th vel oci ty i s r educed w hen compar ed to si ngl etons fr om at l east as ear l y as 30 w eek s' gestati on. Tw i n speci fi c var i abl es such as chor i oni ci ty, sex, bi r th or der and subsequent pr ematur e bi r th do not need to be accounted for i n the i nter pr etati on of gr ow th vel oci ti es i n tw i ns. The cl i ni cal i mpor tance of deter mi ni ng foetal gr ow th vel oci ty i n tw i n pr egnanci es aw ai ts fur ther pr ospecti ve study.Keyw or ds: foetal grow th vel oci ty, tw i ns, chori oni ci ty, foetal sex, bi rth order, preterm and term delivery

A Matched Cohort Comparison of the Outcome of Twin Versus Singleton Pregnancies in Flanders, Belgium

“…This study confirms a lower birthweight in twins after 28 weeks gestational age, some authors have even advocated using twin-adjusted charts for ultrasound-determined fetal growth monitoring (Taylor et al,1998 Our study participants are matched for gestational age, fetal sex and maternal parity; the influence of these factors on birthweight can be excluded. The data do not confirm the general opinion that maternal hypertensive disorders are more frequent in twin gestation (Campbell & McGillivray, 1999).…”

Studies of Twins: Can they Shed Light on the Fetal Origins of Adult Disease Hypothesis?

“…As a group, twins have lower birthweight than singletons. This relates partly to decreased median gestation length in twins, and partly to reduced size for gestation (Taylor et al, 1998). Some investigators have compared mortality after age 6 years, cardiovascular mortality or risk of CHD in twins (as a group) with that in singletons, on the grounds that if people with lower birthweight have an increased risk of later disease, then twins should be at higher risk than singletons.…”

The Foetal Origins of Adult Disease: Interpreting the Evidence From Twin Studies

“…From studies of twin deliveries it appears that it is only after 30-32 weeks that there is a measurable deficit in twins compared to singletons delivered at the same age (McKeown & Record, 1952). More recent ultrasound studies, however, suggest that growth velocity in twins may be depressed earlier than 30 weeks (Taylor et al, 1998).…”