J. S. K. Woo

Zinc deficiency is not a cause for abortion, congenital abnormality and small‐for‐gestational age infant in Chinese women

Summary. Zinc concentration in serum and hair was measured in a cross‐sectional study of 437 Chinese women of whom 310 were normal controls studied at various stages of pregnancy and up to 12 months after delivery. The rest had spontaneous abortions, fetuses with a birthweight below the 10th centile for gestation or congenital abnormalities. Zinc concentration fell throughout normal pregnancy, the fall being greater in serum than in hair. There was no correlation between serum and hair levels. The infant birthweight had a positive correlation with serum level but a negative correlation with hair level. Abortion, low birthweight and congenital abnormality were not associated with low concentrations of zinc in plasma or hair.

Aetiological Factors in the Genesis of Pregnancy Hydronephrosis

Summary: In order to identify possible aetiological factors in the genesis of physiological hydronephrosis in pregnancy, the degree of pelvic‐calyceal dilatation in 90 asymptomatic pregnant women was correlated with levels of plasma oestradiol, progesterone, 24‐hour urinary oestriol, the site of the placenta, birth‐weight of the fetus, and pelvic inlet measurements. A grading system based on maximum calyceal diameter was used; 90% of the patients were found to have at least mild dilatation on the right side. No correlation was demonstrated between the degree of hydronephrosis and the levels of oestradiol, progesterone and 24‐hour urinary oestriol excretion. The birth‐weight of the fetus and its relationship with the pelvic inlet measurements also did not correlate with the occurrence of hydronephrotic changes in the kidneys. The only significant positive finding was a higher incidence of moderate and severe hydronephrosis occurring in patients with a right‐sided placenta than compared with the left (x2= 4.77; p < 0.05), although the sensitivity and specificity in predicting hydronephrosis from a right‐sided placenta is low (53% and 66% respectively). Our results support the hypothesis of a mechanical aetiology in the genesis of pregnancy hydronephrosis, where vascular compression on the ureters may be an important contributory factor. Our study has also shown that urinary tract infection and reduction of creatinine clearance were not more common in patients with moderate or severe pelviccalyceal dilatation.

Chorioangioma of the placenta: an ultrasonic study. Case report

Chorioangioma and trophoblastic tumours are the most common primary tumours of the placenta. The incidence of chorioangioma is about 1% (Wallenburg 1971; Sprit & Kagan 1980). Apparently, only tumours that exceed 5 cm in diameter. or that are multiple, are clinically significant and these cases are relatively rare (Wallenburg 1971). In the majority of patients diagnosis is made after the delivery of the placenta. The role of ultrasound in the diagnosis of placental abnormalities has now been recognized (Mulhern ef al. 1980), but only a few reports have described the ultrasound appearance of chorioangioma in situ (Asokan et al. 1978; Dao et al. 198 1 ; OMalley et ai. 198 1).

ADVANCED PREGNANCY IN THE RUDIMENTARY HORN OF A BICORNUATE UTERUS

Abstract. Ultrasound was useful for the diagnosis of advanced pregnancy in the non‐communicating rudimentary horn of a bicornuate uterus. The role of ultrasonography in early diagnosis of this condition in order to improve fetal salvage was discussed.

Estimation of Fetal Weight in Utero from Symphysisfundal Height and Abdominal Girth Measurements

Summary: The ability to estimate fetal weight accurately from symphysisfundal height (SFH) and abdominal girth (AG) measurements was evaluated. Multivariate regression analysis was performed on measurements made on 208 primigravidas within 48 hours of delivery. A better correlation with birth‐weight was obtained with the SFH than with the AG. The equation BW = ‐1.515 + 0.092 (SFH) + 0.016 (AG) yielded a coefficient of multiple correlation of 0.7259. Using this equation, the mean percentage prediction errors were 5.7%± 4.2(SD) in fetuses between 2,500 and 3,500g (n=156), 9.4%± 5.25(SD) in those larger than 3,500g (n = 33), and 19.1 %± 8.2(SD) in those smaller than 2,500g (n = 19). All the generated equations similarly underestimated the fetal weight in the larger babies and overestimated in the smaller babies. Inclusion of quadratic and logarithmic functions as well as skin‐fold thickness measurements into the equations did not decrease the error or alter the distribution of errors. It was concluded that although fetal weight estimation may be reasonably accurate between 2,500g and 3,500g, the error is too great for the method to be clinically useful in the smaller and larger babies. Moreover, a theoretical basis for a high sensitivity in the detection of small for dates fetuses from these parameters would be difficult to establish.

Ultrasonic Detection of Maternal Ascites in Patients with Severe Pre‐Eclampsia

Summary: Ultrasonography is a reliable method in the detection of free fluid in the abdomen. In 2 patients with severe pre‐eclampsia, maternal ascites was diagnosed by ultrasound. Both babies were delivered prematurely by Caesarean section, indicated by deteriorating maternal condition. One of the babies died in the early neonatal period. The sonologist should be aware of the possible presence of peritoneal free fluid in patients with severe pre‐eclampsia, and be able to demonstrate this accordingly in the ultrasonogram.

Pregnancy Hydronephrosis — A Longitudinal Ultrasonic Evaluation

Summary: The progression of physiological hydronephrosis through the 3 trimesters of pregnancy was assessed by ultrasonic measurement of calyceal diameters in 56 asymptomatic patients in a longitudinal study. A grading system basing on the maximum calyceal diameter was used; 89% of the patients showed at least mild dilatation before delivery. There was a preponderance of the right side being affected. In 6 patients (10.7%), severe dilatation was demonstrable and in all of them its onset appeared to be in the second trimester. The likelihood of progression to moderate or severe dilatation when only mild dilatation is demonstrated in the second trimester is low. Furthermore, it is not common for moderate dilatation in the second trimester to progress to severe dilatation in the third trimester. These findings appear to support the mechanical theory in the genesis of pregnancy hydronephrosis. Rapid regression of calyceal dilatation is not apparent in the first 5 days after delivery.

Partial Hydatidiform Mole: Ultrasonographic Features

Four patients with partial hyatidiform mole managed at the Queen Mary Hospital, Hong Kong, are described. The diagnosis of blighted ovum or missed abortion was made on the sonographic findings prior to suction evacuation. The dominant features in these cases consisted of a relatively large central transonic area bearing the appearance of an empty gestational sac and surrounded by a thick rim of low‐level placenta‐like echoes; in contrast with the case of the blighted ovum, a well‐defined echogenic sac wall is absent. In another 9 patients with molar pregnancy managed during the same period, the more typical ‘snow‐storm’ vesicular appearence was present. It was concluded that the anembryonic appearance described should alert the sonologist and clinician to the possible diagnosis of partial hydatitiform mole. The evacuated material from the uterine cavity should be examined morphologically and if possible cytogenetically.

Intrauterine death from ergotamine overdosage

Fetal death in a primigravid patient who had taken an overdose of ergotamine tartrate is presented. Non-stress cardiotocography performed shortly after admission was technically unsatisfactory for interpretation but revealed the presence of very frequent uterine contractions. The cause of fetal death in this patient is discussed. Overdosage of ergotamine must be considered a serious threat to the well-being of the fetus in utero.

Maternal determinants of birthweight in normal pregnancy

Partial and multiple regression analysis was performed to find out the correlation between birthweight and maternal anthropometric variables. Pearson regression analysis revealed significant dependence of birthweight on gestation of pregnancy, maternal weight, symphysis‐sternal distance and height, but not on armspan and skin thickness. However, the only maternal variable bearing significant influence on birthweight in partial regression analysis was bodyweight. The effects of maternal determinants on birthweight, though some of them were statistically significant, were clinically unimportant.