Factors associated with neonatal hypoglycemia in premature twins and singletons

The effects of birth weight discordance and prematurity on twin neonatal outcome

OBJECTIVE

The purpose of this study was to determine the effect of birth weight discordance (BWD) and prematurity on twin neonatal outcome by measuring Apgar scores and blood glucose concentrations at birth.

METHODS

This was a retrospective cross-sectional study. All twins born at NY Methodist Hospital between January 1998 and December 2001 were eligible. Excluded were fetal deaths, maternal systemic disease, maternal infections, major neonatal malformations, neonates with birth weight < 500 g and multiple gestation greater than 2. BWD was defined as intrapair difference in birth weight expressed as percentage of the larger twin greater than 20% and prematurity as gestation of less than 37 weeks. Hypoglycemia was defined as blood glucose concentration < 40 mg/dl.

RESULTS

There were 75 (48%) preterm and 80 (52%) term twin pairs. Nineteen (12%) of the preterm and 15 (9.6%) of the term showed BWD. Mean Apgar scores at 1 and 5 minutes were higher for the term twins as expected. Neither prematurity nor hypoglycemia was present predominantly in BWD twins. Twelve of the preterm and six of the term BWD twins showed evidence of hypoglycemia.

CONCLUSION

Hypoglycemia in the early hours of postnatal life is relatively common in preterm BWD twins. Blood glucose measurement using reagent strips is an efficient way of monitoring blood glucose concentrations in these infants.

Cerebral morbidity in preterm twins

BACKGROUND

Whether twins are more prone to increased neonatal morbidity than singletons remains controversial. It was the aim of this study to define the special risks of preterm twins with an emphasis on cerebral morbidity.

METHODS

A retrospective chart review was carried out of all consecutively born twins (n = 230) and the corresponding sets of singletons of a single level-III neonatal intensive care unit. The subjects had a gestational age between 24 and 37 weeks, and were born in 1990-98.

RESULTS

Twin pregnancies were more often complicated by preterm contractions (odds ratio (OR) 4.03 (95% confidence interval (CI) 2.39, 6.78)) whereas gestosis was significantly less (OR 0.14 (95% CI 0.05, 0.41)). Grades III and IV intracranial bleeding occurred significantly more often in twins compared to singletons (OR 3.75 (95% CI 1.65, 8.97)), with infants of less than 32 weeks' gestational age being predominantly affected (OR 3.31 (95% CI 1.33, 8.29)). Infants of less than 32 weeks' gestational age developed respiratory distress syndrome more often than the corresponding singletons (OR 1.93 (95% CI 1.15, 3.25)). There were no differences in all observed items between the first- and second-born twins.

CONCLUSION

Twins of less than 37 weeks' gestational age were significantly more often affected by high-grade intraventricular hemorrhage irrespective of birth order. Periventricular leukomalacia occurred twice as often as in singletons. There were no differences with respect to mortality and further morbidity except for respiratory distress syndrome in preterm twins of less than 32 weeks' gestational age.

Birth weight references for twins

OBJECTIVE

We sought to formulate fetal and birth weight references for twins from longitudinal data.

STUDY DESIGN

This historic cohort study was based on 1831 pregnancies of twins born alive at >/=28 weeks' gestation from Baltimore, Maryland; Miami, Florida; Charleston, South Carolina; and Ann Arbor, Michigan.

RESULTS

When we compared singletons and twins, the percentiles of twins fell substantially below the 10th percentile of singletons by 28 weeks' gestation, below the 50th percentile by 30 weeks' gestation, and below the 90th percentile by 34 weeks' gestation. The difference at the 50th percentile was 147 g (10%) at 30 weeks' gestation, 242 g (14%) at 32 weeks' gestation, 347 g (17%) at 34 weeks' gestation, 450 g (19%) at 36 weeks' gestation, 579 g (22%) at 38 weeks' gestation, and 772 g (27%) at 40 weeks' gestation.

CONCLUSION

This new reference demonstrates that, although the overall pattern of fetal growth is slower for twins versus singletons from about 30 weeks' gestation, well-grown twins and singletons do not differ as much as previously believed.

Level of anxiety in parents of high-risk premature twins

We attempted to define parental anxiety in a population of parents of high-risk premature twins (mean birth weight 1,493 +/- 227 kg; mean gestational age 33 +/- 3.5 weeks), admitted to III level NICU. We specifically examined the following factors; gestational age of the twins, whether or not the twins had ventilatory support, pulmonary sequelae, major malformations or intra-ventricular hemorrhage, parental gender and highest level of education obtained by the parent. In the immediate pre-discharge period and a month later, a questionnaire (State-Trait Anxiety Inventory) was given to all parents of premature twins presenting for the discharge. The parents of 30 twins entered the study twice, at the discharge of their first twin (mean postnatal age 40 +/- 32 days), and one month later. They included 15 mothers and 11 fathers, aged 33 +/- 5.5 and 33 +/- 4.2 years, and at the second evaluation 11 mothers and 10 fathers, respectively. As case-controls we examined parental anxiety of fifteen consecutive singleton high-risk prematures, with equal gestational age, discharged immediately after. Our results indicate that the parents of high-risk twin and singleton prematures present an elevated, lasting state-trait anxiety level. Pre- and post-discharge parental anxiety is more elevated (not significant) in twinning with respect to the prematurity alone. When assessed separately by parental gender, in both these groups an increased (not significant) anxiety was persistently found in the mothers. We recommend that, although neonatologists generally define the discharge of the high-risk premature based upon the acquired stabilization of vital parameters, they pay special attention to the twin group we have identified which is at increased risk for predischarge parental anxiety.