title: Homocysteine levels in amniotic fluid. Relationship with birth-weight.
abstract: Hyperhomocysteinemia could play a similar role in the placenta to that played in adults at risk of thrombosis. Moreover, hyperhomocysteinemia in women is described to be associated with the birth of small for gestational age (SGA) newborns, although there are discrepancies on this issue. To date, there is no biochemical marker predictive of SGA in a given pregnancy. We verified the presence of a relationship between homocysteine in amniotic fluid at mid-pregnancy and birth-weight. Amniotic fluid was obtained from 459 healthy women undergoing midtrimester amniocentesis (17.1 +/- 1.2 weeks) because of maternal age. Homocysteine levels were measured in 434 (10 twin) pregnancies. In addition, femur length (FL) and biparietal diameter (BPD) were measured. Outcome of pregnancy was recorded. 233 (53.7%) foetuses were males, 201 (46.3%) females. The mean homocysteine concentration was 1.04 +/- 0.72 microM, (95% C.I. 0.43-2.41). An univariate analysis showed the presence of an association with gestational age, FL, BPD. A multiple linear regression showed that homocysteine levels were significantly associated with FL (p < 0.001) and BPD (p = 0.011). After excluding twin pregnancies, 31 newborns (7.3%) were classified as SGA. Mean birth-weight was 2390 g in SGA, whereas it was 3360 g in 393 adequate for gestational age (AGA) newborns (p < 0.001). The adjusted mean level of homocysteine was significantly lower in AGA (1.01 microM; 95% C.I: 0.94-1.08) than that recorded in pregnancies resulting in a SGA (1.29 microM; 95% CI: 1.05-1.51; p = 0.03). In a large setting, these data provide reference values for homocysteine in amniotic fluids. Moreover, they suggest that homocysteine levels in amniotic fluids may be higher in pregnancies with a SGA newborn.
authors.affiliation: Unità di Aterosclerosi e Trombosi, Poliambulatorio Giovanni Paolo II, IRCCS Casa Sollievo della Sofferenza S. Giovanni R. (FG), 71013 Italy. grandone@katamail.com
authors.forename: Elvira
authors.initials: E
authors.lastname: Grandone
authors.forename: Donatella
authors.initials: D
authors.lastname: Colaizzo
authors.forename: Gennaro
authors.initials: G
authors.lastname: Vecchione
authors.forename: Natale
authors.initials: N
authors.lastname: Sciannamè
authors.forename: Angelo
authors.initials: A
authors.lastname: Notarangelo
authors.forename: Anna Irma
authors.initials: AI
authors.lastname: Croce
authors.forename: Maurizio
authors.initials: M
authors.lastname: Margaglione
mesh_terms: D000328:Adult; D000653:Amniotic Fluid / Q000378:metabolism*; D001724:Birth Weight; D002869:Chromosome Aberrations; D005260:Female; D006710:Homocysteine / Q000096:biosynthesis*; D006801:Humans; D020138:Hyperhomocysteinemia / Q000175:diagnosis / Q000378:metabolism; D007231:Infant, Newborn; D007236:Infant, Small for Gestational Age; D008297:Male; D011247:Pregnancy; D011256:Pregnancy Outcome; D011296:Prenatal Diagnosis; D014427:Twins
chemical_list: D006710:Homocysteine