Serial third trimester ultrasound examinations in predicting fetal weight

Öz

Objective: The aim of this study was to compare the ac­curacy of estimated fetal weights obtained by ultrasonog­raphies performed at different weeks in the third trimester and just before delivery. Methods: A total of 664 patients underwent three serial ultrasonographic examinations in the third trimester. The sonographically estimated fetal weight was calculated us­ing the Hadlock formula and then converted into percen­tiles. The estimated fetal weight percentiles were com­pared with the actual birth weight percentiles at delivery. Results: Mean maternal age was 30±4 years (18-42 years), mean gestational age at first ultrasound was 32±0.5 weeks (30.4-33.6 weeks), mean gestational age at second ultrasound was 36±0.4 weeks (35-36.9 weeks), mean gestational age at third ultrasound was 38.6±1 weeks (36.3– 42 weeks). Mean gestational age at deliv­ery was 39± 1 weeks (36-42 weeks), mean birth weight was 3422±423 grams (1900-4900 grams). Correlation coefficients of estimated fetal weights percentiles at first, second and third ultrasounds were significantly correlated with birth weight percentiles (r=0.556, p

Anahtar Kelimeler

• Fetal weight estimation, third trimester ultra­sound, Hadlock formula

Ardışık üçüncü trimester ultrason incelemeleri ile fetal ağırlığın tahmin edilmesi

Öz

Amaç: Bu çalışmanın amacı, üçüncü trimesterin değişik haftalarında ve doğumdan hemen önce yapılan ultraso­nografik ölçümlerin tahmini fetal ağırlığı tespit etmedeki doğruluğunu belirlemektir. Yöntemler: Toplam 664 hastanın üçüncü trimesterde ya­pılmış 3 adet ultrasonografik verisi elde edildi ve Hadlock formülü ile tahmini doğum ağırlığı ve persentili hesaplan­dı. Daha sonra tahmini fetal ağırlık persentilleri, doğum­daki gerçek ağırlık persentili ile karşılaştırıldı. Bulgular: Ortalama anne yaşı 30±4 (18-42) yıl, ilk üçüncü trimester ultrasonunun yapıldığı hafta ortalaması 32±0.5 hafta (30.4-33.6 hafta), ikinci ultrasonun yapıldığı hafta ortalaması 36±0.4 hafta (35-36.9 hafta), üçüncü ultraso­nun yapıldığı hafta ortalaması 38.6±1 hafta (36.3– 42 haf­ta). Doğumun gerçekleştiği ortalama gebelik haftası 39±1 hafta (36-42 hafta), ortalama doğum kilosu 3422±423 gram (1900-4900 gram). Birinci, ikinci, üçüncü ultrason ölçümlerinde elde edilen persentillerin doğum ağırlığı persentili ile korelasyonu (sırasıyla, r=0.556, p

Anahtar Kelimeler

• Tahmini doğum ağırlığı, üçüncü tri­mester ultrasonu, Hadlock

Kaynakça

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