Ultrasonic evidence of placental calcification at 36 weeks' gestation: maternal and fetal outcomes.
BACKGROUND
To determine the significance of an inappropriately mature placenta on ultrasound examination (Grannum classification), in a low-risk obstetric population. Scans were performed at 36 weeks' gestation. The study group comprised patients demonstrating a grade III placenta, and the control group comprised patients not demonstrating a grade III placenta.


METHODS
A total of 1802 low-risk patients were scanned using serial directed real-time ultrasound at 36 weeks' gestation to determine placental maturity.


RESULTS
The incidence of a grade III placenta at 36 weeks' gestation was 3.8% (68/1802). A grade III placenta was associated with young maternal age and cigarette smoking, p < 0.01. The incidence of proteinuric pregnancy-induced hypertension in the study and control groups was 7.4% (5/68) and 1.56% (27/1734), respectively, p < 0.01. The proportion of infants with a weight less than the 10th centile at birth in the study and control groups was 17.6% (12/68) and 5.6% (97/1734), respectively, p < 0.01.


CONCLUSIONS
Ultrasound detection of a grade III placenta at 36 weeks' gestation in a low-risk population helps to identify the "at-risk" pregnancy. It helps to predict subsequent development of proteinuric pregnancy-induced hypertension and may help in identifying the growth-restricted baby.
McKenna
Daniel
D
The Royal Jubilee Maternity Hospital, Grosvenor Road, Belfast, Northern Ireland, UK. dan.mckenna@virgin.net
Tharmaratnam
Suresh
S
Mahsud
Samina
S
Dornan
James
J
D000328:Adult; D002114:Calcinosis / Q000000981:diagnostic imaging* / Q000453:epidemiology; D016022:Case-Control Studies; D005260:Female; D005865:Gestational Age; D006801:Humans; D008423:Maternal Age; D010922:Placenta Diseases / Q000000981:diagnostic imaging* / Q000453:epidemiology; D011225:Pre-Eclampsia / Q000000981:diagnostic imaging / Q000453:epidemiology; D011247:Pregnancy; D011256:Pregnancy Outcome; D018566:Pregnancy, High-Risk; D011446:Prospective Studies; D012307:Risk Factors; D012907:Smoking / Q000453:epidemiology; D016216:Ultrasonography, Prenatal