Cardiac function in fetuses of poorly-controlled pre-gestational diabetic pregnancies--a pilot study.

OBJECTIVE: Cardiac impairment is frequently found in babies of diabetic mothers. It is still controversial whether this is due to poor glucose control. The aim of this study is to compare the cardiac function in fetuses of well- and poorly-controlled pre-gestational diabetic pregnancy in third trimester. METHODS: Women with type 1 pre-gestational diabetes were enrolled at 30-32 weeks. Cardiac size and interventricular septal wall thickness were measured by M-mode at end-diastolic phase. The right and left ventricular ejection fractions were calculated. At the mitral and tricuspid valves inflow, the ratio between early ventricular filling and active atrial filling (E/A) at both atrioventricular valves were measured by Doppler echocardiography. Peak velocities of ascending aorta and pulmonary artery were assessed. The angle of isonation was kept at <20 degrees. Women with poorly-controlled diabetes (HbA1c>6.5%) were compared with those with satisfactorily controlled diabetes (HbA1c < or = 6.5%). RESULTS: A total of 21 women with pre-gestational diabetes were recruited for this study. Eight women with well-controlled diabetes were compared with 9 women who had poorly-controlled diabetes. HbA1c in the poorly-controlled group was 7.3% and in the well-controlled group it was 5.4% (p<0.001). There was no difference between the two groups in cardiac size, interventricular septal wall thickness, ejection fraction, aorta and pulmonary artery peak flow velocities. The right atrioventricular E/A ratio was significantly lower among the poorly-controlled diabetic pregnancies (0.71 vs. 0.54; p<0.05). CONCLUSION: Fetuses of poorly-controlled diabetic mothers had a lower right atrioventricular E/A ratio. This may be due to metabolic acidosis, non-hypertrophic cardiac dysfunction or fetal polycythemia.

Factors influencing the prenatal detection of structural congenital heart diseases.

OBJECTIVE: To assess the factors influencing the prenatal detection rate of structural congenital heart diseases (CHDs). METHODS: A retrospective study was conducted at a major obstetric hospital in Australia between 1 January 1996 and 30 June 1999. The medical records of all fetuses and infants born with CHD, except those with isolated patent ductus arteriosus or secundum atrial septal defect, were reviewed. Only pregnancies that had prenatal ultrasound scan assessments for morphological surveys were included. The following factors that may influence the detection rate were assessed: complexity of the lesions; experience of the sonographers (performance in tertiary versus non-tertiary institutions); presence of other structural or chromosomal anomalies; and maternal body mass index (BMI). RESULTS: The incidence of structural CHD in this series, excluding cases referred from other hospitals, was 7.0 per 1000 (179/25 529). Of the 179 pregnancies with CHD, 151 had prenatal ultrasound scans and were included in the study. The overall detection rate for CHDs in this series was 40.4%. The detection rate for isolated septal defects was poor (13.7%). The detection rates were significantly higher for complex lesions (54%), for lesions with concomitant septal defects (66.7%), and for lesions with abnormal four-chamber views (62.9%). The detection rate was also higher if the scan was performed in the tertiary institution, and if there were other chromosomal or structural anomalies. Maternal BMI did not affect the detection rate in the current series. Stepwise logistic regression analysis showed that three independent variables affecting the detection rate were complexity of the cardiac lesion, experience of the operator, and the detection of chromosomal anomalies. CONCLUSION: A high detection rate for major CHDs can be achieved in a screening setting but there is still room for improvement in scanning skills in the four-chamber view and great-artery analysis in both tertiary and local centers.

Routine ultrasound screening in diabetic pregnancies.

OBJECTIVES: To assess the detection rate of congenital fetal malformations and specific problems related to routine ultrasound screening in women with pre-existing diabetes. METHODS: A retrospective study was carried out to assess the performance of routine ultrasound screening in women with pre-existing diabetes (Types 1 and 2) within a tertiary institution. The incidence, type and risk factors for congenital fetal malformations were determined. The detection rate of fetal anomalies for diabetic women was compared with that for the low-risk population. Factors affecting these detection rates were evaluated. RESULTS: During the study period, 12 169 low-risk pregnant women and 130 women with pre-existing diabetes had routine ultrasound screening performed within the institution. A total of 10 major anomalies (7.7%) and three minor anomalies (2.3%) were present in the fetuses of the diabetic women. Central nervous system and cardiovascular system anomalies accounted for 60% of the major anomalies. Periconceptional hemoglobin A1c of more than 9% was associated with a high prevalence of major anomalies (143/1000). Women who had fetuses with major anomalies had a significantly higher incidence of obesity (78% vs. 37%; P < 0.05). Ultrasound examination of these diabetic pregnancies showed high incidences of suboptimal image quality (37%), incomplete examinations, and repeat examinations (17%). Compared to the 'low-risk' non-diabetic population from the same institution, the relative risk for a major congenital anomaly among the diabetic women was 5.9-fold higher (95% confidence interval, 2.9-11.9). The detection rate for major fetal anomalies was significantly lower for diabetic women (30% vs. 73%; P < 0.01), and the mean body mass index for the diabetic group was significantly higher (29 vs. 23 kg/m2; P < 0.001). CONCLUSION: The incidence of congenital anomalies is higher in diabetic pregnancies. Unfortunately, the detection rate for fetal anomalies by antenatal ultrasound scan was significantly worse than that for the low-risk population. This is likely to be related to the maternal body habitus and unsatisfactory examinations. Methods to overcome these difficulties are discussed.

Anticoagulation in pregnancy and the puerperium.

For the management of acute thrombotic events in pregnancy therapeutic doses of low molecular weight heparins (LMWH) may be used, unless the shorter half-life of intravenous unfractionated heparin (UH) and predictable reversibility by protamine are important. Treatment should be continued up until delivery and into the puerperium. Pregnant women who have had an acute thrombotic event should be delivered by a specialist team. In the case of recent thrombosis, delivery should be planned and the time during which anticoagulation therapy is ceased around the time of delivery should be minimised. Therapeutic doses of LMWH contraindicate the use of regional anaesthesia, and a switch to intravenous UH before delivery may allow greater flexibility in this regard. Prophylactic doses of LMWH can be used to reduce the risk of recurrent thromboembolic events in pregnancy. The regimen used will depend on the previous history, the family history and the presence of risk factors, including the genetic and acquired causes of thrombophilia. Women with mechanical heart valves are at high risk during pregnancy and require therapeutic anticoagulation throughout pregnancy under the direction of experienced specialists. Low-dose aspirin can reduce the risk of recurrent pre-eclampsia by about 15%, but the role of UH and LMWH in the prevention of recurrent miscarriage or obstetric complications associated with uteroplacental insufficiency is still uncertain.

Sonographic estimation of fetal weight in macrosomic fetuses: diabetic versus non-diabetic pregnancies.

The objective of this study is to compare the accuracy of sonographic estimation of fetal weight of macrosomic babies in diabetic vs non-diabetic pregnancies. All babies weighing 4,000 g or more at birth, and who had ultrasound scans performed within one week of delivery were included in this retrospective study Pregnancies with diabetes mellitus were compared to those without diabetes mellitus. The mean simple error (actual birthweight--estimated fetal weight); mean standardised absolute error (absolute value of simple error (g)/actual birthweight (kg)); and the percentage of estimated birthweight falling within 15% of the actual birthweight between the two groups were compared. There were 9,516 deliveries during the study period. Of this total 1,211 (12.7%) babies weighed 4,000 g or more. A total of 56 non-diabetic pregnancies and 19 diabetic pregnancies were compared. The average sonographic estimation of fetal weight in diabetic pregnancies was 8% less than the actual birthweight, compared to 0.2% in the non-diabetic group (p < 0.01). The estimated fetal weight was within 15% of the birthweight in 74% of the diabetic pregnancies, compared to 93% of the non-diabetic pregnancies (p < 0.05). In the diabetic group, 26.3 % of the birthweights were underestimated by more than 15 %, compared to 5.4% in the non-diabetic group (p < 0.05). In conclusion, the prediction accuracy of fetal weight estimation using standard formulae in macrosomic fetuses is significantly worse in diabetic pregnancies compared to non-diabetic pregnancies. When sonographic fetal weight estimation is used to influence the mode of delivery for diabetic women, a more conservative cut-off needs to be considered.

Long term outcome of twin-twin transfusion syndrome.

AIMS: To compare the perinatal mortality and morbidity of infants with twin-twin transfusion syndrome (TTTS) with those of gestation matched twin controls and to assess the neurodevelopmental outcome of surviving twins with TTTS. METHODS: A cohort of 17 consecutive pregnancies with TTTS was enrolled over three years together with gestation matched twin pregnancies unaffected by TTTS. Serial amnioreduction for the TTTS pregnancies was performed as appropriate. Perinatal death and neonatal morbidities were recorded for both the TTTS cohort and controls. The TTTS survivors had neurodevelopmental follow up to at least 2 years of age. RESULTS: In 12 of the pregnancies, serial amniocenteses were performed, but, in five, the infants were born before intervention. The mean gestational age at delivery was 29.1 weeks (range 23-36). There were five intrauterine deaths in the TTTS cohort and six neonatal deaths (survival 68%). In the control group, there was one intrauterine death and five neonatal deaths (survival 82%). Infants in the TTTS group had a greater requirement for inotropes (p = 0.04) and a higher incidence of renal failure (p = 0.005). Periventricular leucomalacia and cerebral atrophy were seen in 17% of the TTTS group, but none of the controls (p = 0.03). The 23 surviving TTTS infants were all followed up, with 22% having significant neurological morbidity: cerebral palsy and global developmental delay. CONCLUSIONS: Twins with TTTS have high perinatal mortality and neonatal morbidity, and long term neurodevelopmental morbidity in survivors is high. Further investigation into the pathogenesis and management of TTTS is required.

Family history of pre-eclampsia as a predictor for pre-eclampsia in primigravidas.

OBJECTIVE: To assess the clinical utility of knowledge of a family history of pre-eclampsia as a predictor for the development of pre-eclampsia in primigravid women. METHODS: 368 primigravid women were prospectively recruited from the outpatients department of an obstetric teaching hospital. Details of any family history of pre-eclampsia were obtained from the women and their subsequent obstetric outcomes were observed. RESULTS: Of 368 primigravid women, 34 (9.2%) developed pre-eclampsia. Eighteen (4.9%) women of the total group stated that they had a mother (12), sister (five) or both (one) who had had pre-eclampsia. Of these 18 women, five (27.8%) developed pre-eclampsia. Of the women who had no family history, 29 (8.3%) developed pre-eclampsia (relative risk, RR = 3.4; 95% CI, 1.5-7.6; P = 0.018). Four (22.2%) of the women with a positive family history developed severe pre-eclampsia compared to 18 (5.1%) with a negative family history (RR = 4.3; 95% CI, 1.6-11.5; P = 0.017). CONCLUSIONS: In a primigravida, a family history of pre-eclampsia is associated with a fourfold increased risk of severe pre-eclampsia. This clinical history identifies a group who warrant close clinical surveillance during pregnancy and who may be suitable for trials of prophylactic interventions.

Thrombolytic therapy for basilar artery thrombosis in the puerperium.

A case is presented of a woman in whom basilar artery thrombosis developed 14 days post partum. She was successfully treated with intraarterial urokinase. This case demonstrates that complete neurologic recovery can be achieved after recanalization of the basilar artery with thrombolytic therapy.

Pseudosinusoidal fetal heart rate pattern and fetal anaemia: case report and review.

The association of a pseudosinusoidal fetal heart rate pattern with fetal anaemia is reported. A system of classifying this cardiotocographic feature as minor, intermediate or major is discussed. The clinical correlates of each of these gradings and the differentiation from a true sinusoidal fetal heart rate pattern are presented.