Multiple gestation

Predicting concordance of biochemical lung maturity in the preterm twin gestation

OBJECTIVE

To propose a strategy for lung maturity amniocentesis in diamnionic twin gestations by exploiting indicators of concordance of lung maturity status.

METHODS

Amniotic fluid from 92 diamnionic twin gestations was assayed for lung maturity by standard methodology. The rates of concordance of lung maturity status between twins were calculated after stratification by gestational age, chorionicity, gender and weight discordance.

RESULTS

At the extremes of gestational age (28, 29, 36 and 37 weeks), twins are 100% concordant in lung status; for twins of 33-35.9 gestational weeks, lung concordance is significantly lower at 0.91 (p = 0.02); for 30-32.9 weeks, a rate of 0.52 is even lower (p = 0.001). Same-gender twin pairs of 33-35.9 weeks and twin pairs with estimated fetal weight discordance exceeding 20% or less than 10% were uniformly concordant in their lung maturity.

CONCLUSION

Non-selective single amniocentesis may be performed if the gestational age is greater than 35.9 weeks. Double amniocentesis should be performed in the following: twins of 30-32.9 gestational weeks and twins of 33-35.9 weeks unless the twin pair is gender-concordant, or calculated fetal weight discordance is less than 10% or greater than 20%.

Management and outcome of 21 triplet and quadruplet pregnancies

The course of gestation and the outcome of fifteen triplet and six quadruplet pregnancies are reviewed. Twenty pregnancies followed induction of ovulation and only one was spontaneous. Bed rest, the use of beta-mimetics and betamethasone, and prolonged hospitalisation were part of the management. Elective cervical suture was not used. The most frequent antenatal complications were preterm labor, preterm rupture of membranes and pregnancy-induced hypertension. The median gestational age was 33.5 weeks in the triplets and 32 weeks in the quadruplets. The overall perinatal and neonatal mortality was 4.9%. The neonatal complications resulted from prematurity and sepsis.