Multifetal pregnancy reduction and selective termination

Comparing pregnancy outcomes and loss rates in elective twin pregnancy reduction with ongoing twin gestations in a large contemporary cohort

BACKGROUND

As compared with singleton gestations, twin pregnancies are associated with a significantly higher risk of preterm birth and maternal complications as well as fetal and neonatal morbidity and mortality. Multifetal pregnancy reduction is a technique developed in the 1980s to reduce the fetal number in higher-order multiple pregnancies to reduce the risk of adverse pregnancy outcomes, most importantly preterm birth.

OBJECTIVE

The objective of the study was to compare pregnancy outcomes and loss rates in elective twin pregnancy reduction to ongoing twin gestations in a large contemporary cohort.

STUDY DESIGN

This was a retrospective review of dichorionic diamniotic twin gestations that underwent first-trimester ultrasound at our institution from January 2008 to September 2016. Planned elective 2-to-1 multifetal pregnancy reductions at less than 15 weeks' gestation were compared with ongoing dichorionic diamniotic twin gestations. Data were collected via chart review. Demographics between 2-to-1 reduced singletons and ongoing twins were assessed using a Student t test or a Wilcoxon rank-sum test, as appropriate, for continuous variables and χ² or Fisher exact tests, as appropriate, for categorical variables. Univariable and multivariable logistic regressions were used to compare pregnancy outcomes between ongoing twins and reduced singletons adjusting for maternal age, body mass index, race, in vitro fertilization, use of chorionic villus sampling, prior term birth, and prior preterm birth.

RESULTS

Of 1070 dichorionic diamniotic twin pregnancies identified, completed follow-up data were available and analyzed for 855 patients (79.9%). Among those, 250 (29.2%) were 2-to-1 singletons and 605 (70.8%) were ongoing twins. Reduced singleton patients were slightly older, more likely white, and had lower body mass index. They were also more likely to have undergone in vitro fertilization (63.6% vs 48.8%), had chorionic villus sampling (92% vs 37.5%), and had prior term births (54% vs 35.7%). Compared with 2-to-1 singletons, the adjusted odds of having preterm delivery at 37 weeks for ongoing twins were 5.62 times (95% confidence interval, 3.67-8.61; P < .001) and 2.22 times (95% confidence interval, 1.20-4.11; P < .001) at 34 weeks. While intrauterine growth restriction, placental abruption, and gestational diabetes were not significant, ongoing twins were more likely to have a cesarean delivery (odds ratio, 5.53, 95% confidence interval, 3.60-8.49; P < .001) and preeclampsia (odds ratio, 3.33, 95% confidence interval, 1.60-6.96; P < .001) after adjusting for maternal characteristics. There were also significant differences between groups for preterm premature rupture of membranes and low birthweight at less than the fifth and 10th percentiles. Total pregnancy loss (at 24 and 20 weeks) was similar between singleton and ongoing twins (4% vs 2.5%, P = .23, and 3.6% vs 1.7%, P = .09 for respective weeks). There were no significant differences in the rate of unintended pregnancy loss (2.4% vs 2.3%; P = .94) and the rate of intrauterine fetal death greater than 24 weeks (1.2% vs 0.7%; P = .43) in reduced singleton versus ongoing twin group, respectively.

CONCLUSION

In our study, patients who elected to reduce to a singleton pregnancy had a higher gestational age of delivery and lower rates of preterm birth and pregnancy complications without an increased risk of pregnancy loss.

Variable outcome in quintuplets pregnancy based on obstetric care

The incidence of multiple pregnancies has increased dramatically over the last few years in developed countries, largely attributed to delayed childbearing and the increasing use of assisted reproduction technologies and ovulation inducing hormones. Relatively few countries have population-based statistics covering birth statistics. Of those that do, the numbers of quintuplet pregnancies rose sharply in the nineties while, at the same time, their delivery rates decreased greatly because of the use of fetal reduction. Fetal reduction is not possible or legal in some countries, Poland being one of them, and therefore obstetricians are faced with the challenges of quintuplet deliveries. Conservative treatment and management is difficult, and outcomes often vary greatly. Despite this, expert care provided at tertiary care centers can positively influence outcomes. The objective of this article is to present different care options and their consequences in two illustrative cases, as well as to establish a set of obstetric care and management goals that would allow prolongation of the gestation time. Quintuplet pregnancy is rare but poses relevant clinical problems to both the obstetrician and the neonatologist. It should be managed with close cooperation between all concerned. Due to the extreme and invariable risk of premature delivery associated with quintuplet pregnancies, we recommend early diagnosis, adequate prenatal care at one tertiary medical center, routine hospitalization and bed rest, repeated ante partum ultrasound surveillance with tests of fetal well-being, tocolytic therapy at first signs of the risk of premature labor, and specialized neonatology care after delivery.

Perinatal care improves the outcome of triplets

OBJECTIVE

To compare pregnancy complications and neonatal outcome of 85 triplet gestations cared for during the 15 years in a single perinatal unit.

METHODS

Pregnancies were divided in two groups according to the differences in the management plan and their outcomes were compared. Group I (N = 44) consisted of pregnancies cared from 1986 to 1995, using standard model of care: preventive hospitalization from the early second trimester or home bed rest with routine hospitalization after 28-32 weeks of pregnancy, routine clinical and ultrasound examinations, biophysical profile and non-stress tests starting at 28 weeks, expert neonatal care without free access to surfactant or to parenteral nutrition. Group II (N = 41) consisted of pregnancies cared for from 1986 to 2000 using modified care: preventive hospitalization from early second trimester or home bed rest with routine hospitalization after 32 weeks of pregnancy, biophysical profile, non-stress tests and pulsed doppler analysis of fetal umbilical artery, fetal aorta and middle cerebral artery blood flow from as early as 26 weeks, and neonatal care improved by free access to surfactant and parenteral nutrition.

RESULTS

The mean gestational age, mean birth weight, the proportion of growth-retarded infants, the incidence of various maternal complications and immediate neonatal conditions as judged by APGAR scores did not differ between the groups. The incidence of deliveries up to 28 weeks was lower in the group II in comparison to group I, but the proportion of term and near term deliveries was lower. The incidence of cesarean sections was high (91.8%), but significantly increased cesarean delivery rate because of fetal distress was observed in the group II (P = 0.014). Infants in the group II had less frequently uneventful early neonatal period, mainly due to significantly increased conatal infection (P = 0.007) and neonatal encephalopathy rate (P = 0.001). However, perinatal mortality was decreased from 235% in the group I to 142% in the group II for newborns that reached 24 weeks of gestation or more. The decrease of perinatal mortality was observed also in the newborns born after 28 weeks of gestation (123% in the group I and 99% in the group II). None of the children weighing <1000 g died in utero in the group II. Early neonatal death of infants weighing >1500 g was significantly reduced in the group II (P = 0.048).

CONCLUSION

Advances in neonatal care, but also the delivery of infants in better overall condition must be the explanation for improved outcome of triplet gestations managed by modified care. A higher cesarean section rate because of imminent fetal jeopardy as judged by not only fetal heart rate tracings, but also umbilical, aortic and middle cerebral artery flow analysis, could be the explanation for lowered perinatal mortality and significantly improved outcome in very preterm infants from triplet gestations.

Maternal neonatal outcome in quadruplet and quintuplet versus triplet gestations

OBJECTIVE

Examination and comparison of the natural histories of triplet versus quadruplet and quintuplet gestations.

STUDY DESIGN

A retrospective study of sixty-four multifetal pregnancies (fifty-two sets of triplets, nine sets of quadruplets and three sets of quintuplets) cared for during past 12 years in our department. Quintuplets and quadruplets were compared with triplet pregnancies according to gestational age, birthweight, pregnancy complications and perinatal outcome. Student's t-test, Fisher exact test and chi2 test were used for statistical analysis, considering P value of <0.05 as statistically significant.

RESULTS

Although mean gestational age at delivery between triplets and higher order gestations was not significantly different, birthweight of quadruplets and quintuplets was significantly lower. Pregnancy complications, including intrauterine growth retardation, were equally distributed between the groups. Early neonatal and perinatal mortality were significantly higher in quadruplets and quintuplets than in triplets. Surprisingly, survival of growth retarded fetuses was better than survival of their eutrophic counterparts. The spontaneous loss rate was 11.5% for entire triplet gestation and 16.7% for quadru- and quintuplet pregnancies.

CONCLUSIONS

As the spontaneous loss rate of triplets and higher order pregnancies observed in our study is quite similar to pregnancy loss rate caused by multifetal pregnancy reduction, conservative management of multifetal pregnancies in specialised tertiary centers seems to be a prudent solution.

Cord occlusion techniques for selective termination in monochorionic twins

We wished to determine the optimal method for cord obliteration to perform selective reduction in complicated monochorionic (MC) twin pregnancies under different clinical conditions. For this purpose, we reviewed our experience and the available published literature and unpublished reports. Indications were a cardiac twin pregnancy, twins discordant for fetal anomaly, and severe feto-fetal transfusion syndrome where one twin had a very poor prognosis. Data were available for the following techniques: cord embolization, fetoscopic cord ligation, laser coagulation, monopolar coagulation and bipolar cautery. Unfortunately the data are heterogeneous, incomplete and reports are only sporadic. Cord embolization using coils or sclerosants has a high failure rate and can no longer be recommended. In 23 published cases of fetoscopic cord ligation a failure rate of 10% was reported. After successful ligation an overall fetal survival rate of 71% but a risk of preterm prelabor rupture of the membranes (PPROM) of 30% was documented. Four cases of monopolar coagulation have been published--all in a cardiac twin pregnancies. In three cases the abdominal aorta was coagulated prior to 20 weeks and complete cessation of flow was demonstrated. In 10 cases of bipolar cord coagulation, all procedures were technically successful. Nine of 10 were performed under ultrasound guidance through a single port. In 2 cases, frank PPROM occurred, leading to induction of labor. The other eight fetuses were born at 35 weeks or more. Nd:YAG coagulation of the cord was much more sporadically described; the success of the procedure seems to be clearly dependant on gestational age. In all our attempts prior to 20 weeks, we failed in only one out of 6 cases. In summary, there is little data to perform meaningful comparisons of available techniques for umbilical cord occlusion. Based on practical and technical considerations we use the following clinical algorithm: prior to 21 weeks, we attempt to coagulate the cord with Nd:YAG laser. If this is unsuccessful, or for gestations beyond 21 weeks, bipolar cord coagulation is currently our other method of choice. Sonoendoscopic cord ligation is reserved as backup procedure if neither of these methods are successful.

First trimester ultrasonography of multiple gestations: a review

The objective was to review current literature pertaining to first trimester ultrasonography of multiple gestations. To this goal, all manuscripts published in the English language regarding this topic were selected and reviewed in a MEDLINE search from 1966 through May 1998. Additional sources were identified through cross-referencing. Current widespread application of first trimester ultrasonography and especially transvaginal sonography has introduced a new dimension in both diagnostic and management aspects of multiple gestations. Application of first trimester ultrasonography in multiple gestations enables an earlier and more precise depiction of important anatomical details regarding fetal viability, chorionicity, pregnancy outcome, structural abnormalities, pathophysiology of developmental disorders (such as twin reverse arterial perfusion [TRAP] sequence), early sonographic signs associated with fetal aneuploidy (nuchal translucency and abnormal crown-rump length), and potential fetal growth discordancy. First trimester ultrasonography also assists in guiding operative procedures including: amniocentesis, chorionic villus sampling, and selective fetal reduction. Enhanced information obtained with high-resolution, first trimester transvaginal ultrasonography is rapidly becoming a standard for establishing critical information that will assist clinicians to stratify management of multiple gestations. Given the increasing incidence of multiple gestations because of various assisted reproductive technology modalities, it is important that obstetricians become aware of the potential advantages of first trimester ultrasonography in clinical management of multiple gestations.

Multifetal pregnancy reduction: a review of the world results for the period 1993-1996

The objective of this work was to evaluate the outcome of multifetal pregnancy reduction and to provide an analysis of the ethical dilemmas associated with its application. The study design was based on data on over 1400 completed pregnancies that underwent multifetal pregnancy reduction as reported in the world literature during 1993-1996. The results were: A total of 1453 completed cases of multifetal pregnancy reduction are presented. The total survival rate was estimated to be 87.7%, resulting in a total pregnancy loss rate of 12.3%. The lowest survival rate is found to be in higher-order pregnancies of five or more fetuses (75.2%), whereas pregnancy loss rate seems to be similar for quadruplets, triplets and twins that underwent reduction (11.3%, 8.3% and 13.6%, respectively). A 33.3% of the total pregnancy loss rate occurred within four weeks from the procedure, whereas 66.7% occurred after the four weeks but at 24 weeks of gestation or earlier. The mean gestational age at delivery was estimated to be 33 weeks for pregnancies reduced to triplets, 35.8 weeks for those reduced to twins and 36.9 weeks for singletons, with 5% delivering at less than 28 weeks and 9.6% at 29-32 weeks. We conclude that multifetal pregnancy reduction has been established as an efficient and safe way to improve outcome of multifetal gestations, especially those with four or more fetuses and likely of triplets. As the experience from the procedure increases, it seems that reduction of triplets to twins can be offered to patients with satisfactory results. The reduction to singletons has not yet been established and is being performed only when medical indications exist. Prenatal genetic diagnosis should become an integral part of counselling on multiple pregnancy. Physicians should take whenever possible measures designed to prevent high multiple birth pregnancies. We also note that although multifetal pregnancy reduction improves significantly the outcome of multiple pregnancies, several ethical dilemmas arising from its application are still under dispute.