Prenatal prediction of significant intertwin birthweight discordance using standard second and third trimester sonographic parameters.

INTRODUCTION: Our study aim was to evaluate standard ultrasound-derived fetal biometric parameters in the prediction of clinically significant intertwin birthweight discordance defined as ≥18%. MATERIAL AND METHODS: This was a secondary analysis of a prospective cohort study of 1028 unselected twin pairs recruited over a two-year period. Dichorionic twins underwent two-weekly ultrasonographic surveillance from 24 weeks' gestation, with surveillance of monochorionic twins two-weekly from 16 weeks. Ultrasonographic biometric data from 24 to 36 weeks were evaluated for the prediction of an intertwin birthweight discordance threshold ≥18%. Umbilical artery Doppler waveform data was also analyzed to evaluate whether it was predictive of birthweight discordance. RESULTS: Of the 956 twin pairs analyzed for discordance, 208 pairs were found to have a clinically significant birthweight discordance ≥18%. All biometric parameters were predictive of significant inter-twin birthweight discordance at low cut-offs, with low discriminatory powers when ROC curves were analyzed. Discordance in estimated fetal weight was predictive of a significant birthweight discordance at all gestational categories with cut-offs between 8 and 11%. A low-discriminatory power and poor sensitivity and specificity were also observed. An abnormal umbilical artery Doppler was predictive of birthweight discordance ≥18% between 28 and 32 weeks' gestation, although with poor sensitivity and specificity. CONCLUSIONS: Calculation of estimated fetal weight and birthweight discordance between twins allows minimal margin for error. These margins make it difficult to accurately predict those who are at or above the discordance threshold of 18%. These findings highlight that small intertwin discrepancies in weight and biometry should not be overlooked and merit further investigation.

Maternal mortality and the rising cesarean rate.

OBJECTIVE: To review maternal mortality in a large stand-alone maternity hospital in a European city and to determine whether the increased cesarean rate was associated with an increase in maternal deaths. METHODS: The details of maternal deaths at Coombe Women and Infants University Hospital, Dublin, Ireland, as published in the hospital's Annual Clinical Reports for 1995-2009, were reviewed. Maternal mortality ratio was defined as the number of maternal deaths per 100,000 live births. RESULTS: Over 15 years, 112,326 women delivered 114 170 infants weighing at least 500 g. The cesarean rate increased from 14.1% in 1995 to 26.5% in 2009 (20.0% overall). The maternal mortality ratio was low at 2.7 per 100 000 live births. There were 2 maternal deaths following cesarean, neither of which was attributable to the operation. CONCLUSION: In Ireland, a large stand-alone maternity hospital can achieve a low maternal mortality ratio, according to international standards, despite an increase in cesarean rate over the past 2 decades. There was no evidence that the increased cesarean rate had an adverse impact on maternal mortality ratio.

Body mass index and blood pressure measurement during pregnancy.

OBJECTIVE: The accurate measurement of blood pressure requires the use of a large cuff in subjects with a high mid-arm circumference (MAC). This prospective study examined the need for a large cuff during pregnancy and its correlation with maternal obesity. METHODS: Maternal body mass index (BMI), fat mass, and MAC were measured. RESULTS: Of 179 women studied, 15.6% were obese. With a BMI of level 1 obesity, 44% needed a large cuff and with a BMI of level 2 obesity 100% needed a large cuff. CONCLUSION: All women booking for antenatal care should have their MAC measured to avoid the overdiagnosis of pregnancy hypertension.