Gestational diabetes in twin pregnancies-a pathology requiring treatment or a benign physiological adaptation?

There is level-1 evidence that screening for and treating gestational diabetes in singleton pregnancies reduce maternal and neonatal morbidity. However, similar data for gestational diabetes in twin pregnancies are currently lacking. Consequently, the current approach for the diagnosis and management of gestational diabetes in twin pregnancies is based on the same diagnostic criteria and glycemic targets used in singleton pregnancies. However, twin pregnancies have unique physiological characteristics, and many of the typical gestational diabetes-related complications are less relevant for twin pregnancies. These differences raise the question of whether the greater increase in insulin resistance observed in twin pregnancies (which is often diagnosed as diet-treated gestational diabetes) should be considered physiological and potentially beneficial in which case alternative criteria should be used for the diagnosis of gestational diabetes in twin pregnancies. In this review, we summarize the most up-to-date evidence on the epidemiology, pathophysiology, and clinical consequences of gestational diabetes in twin pregnancies and review the available data on twin-specific screening and diagnostic criteria for gestational diabetes. Although twin pregnancies are associated with a higher incidence of diet-treated gestational diabetes, diet-treated gestational diabetes in twin pregnancies is less likely to be associated with adverse outcomes and accelerated fetal growth than in singleton pregnancies and may reduce the risk for intrauterine growth restriction. In addition, there is currently no evidence that treatment of diet-treated gestational diabetes in twin pregnancies improves outcomes, whereas preliminary data suggest that strict glycemic control in such cases might increase the risk for intrauterine growth restriction. Overall, these findings provide support to the hypothesis that the greater transient increase in insulin resistance observed in twin pregnancies is merely a physiological exaggeration of the normal increase in insulin resistance observed in singleton pregnancies (that is meant to support 2 fetuses) rather than a pathology that requires treatment. These data illustrate the need to develop twin-specific screening and diagnostic criteria for gestational diabetes to avoid overdiagnosis of gestational diabetes and to reduce the risks associated with overtreatment of diet-treated gestational diabetes in twin pregnancies. Although data on twin-specific screening and diagnostic criteria are presently scarce, preliminary data suggest that the optimal screening and diagnostic criteria in twin pregnancies are higher than those currently used in singleton pregnancies.

Vasa previa in singleton pregnancies: diagnosis and clinical management based on an international expert consensus.

BACKGROUND: There are limited data to guide the diagnosis and management of vasa previa. Currently, what is known is largely based on case reports or series and cohort studies. OBJECTIVE: This study aimed to systematically collect and classify expert opinions and achieve consensus on the diagnosis and clinical management of vasa previa using focus group discussions and a Delphi technique. STUDY DESIGN: A 4-round focus group discussion and a 3-round Delphi survey of an international panel of experts on vasa previa were conducted. Experts were selected on the basis of their publication record on vasa previa. First, we convened a focus group discussion panel of 20 experts and agreed on which issues were unresolved in the diagnosis and management of vasa previa. A 3-round anonymous electronic survey was then sent to the full expert panel. Survey questions were presented on the diagnosis and management of vasa previa, which the experts were asked to rate on a 5-point Likert scale (from "strongly disagree"=1 to "strongly agree"=5). Consensus was defined as a median score of 5. Following responses to each round, any statements that had median scores of ≤3 were deemed to have had no consensus and were excluded. Statements with a median score of 4 were revised and re-presented to the experts in the next round. Consensus and nonconsensus statements were then aggregated. RESULTS: A total of 68 international experts were invited to participate in the study, of which 57 participated. Experts were from 13 countries on 5 continents and have contributed to >80% of published cohort studies on vasa previa, as well as national and international society guidelines. Completion rates were 84%, 93%, and 91% for the first, second, and third rounds, respectively, and 71% completed all 3 rounds. The panel reached a consensus on 26 statements regarding the diagnosis and key points of management of vasa previa, including the following: (1) although there is no agreement on the distance between the fetal vessels and the cervical internal os to define vasa previa, the definition should not be limited to a 2-cm distance; (2) all pregnancies should be screened for vasa previa with routine examination for placental cord insertion and a color Doppler sweep of the region over the cervix at the second-trimester anatomy scan; (3) when a low-lying placenta or placenta previa is found in the second trimester, a transvaginal ultrasound with Doppler should be performed at approximately 32 weeks to rule out vasa previa; (4) outpatient management of asymptomatic patients without risk factors for preterm birth is reasonable; (5) asymptomatic patients with vasa previa should be delivered by scheduled cesarean delivery between 35 and 37 weeks of gestation; and (6) there was no agreement on routine hospitalization, avoidance of intercourse, or use of 3-dimensional ultrasound for diagnosis of vasa previa. CONCLUSION: Through focus group discussion and a Delphi process, an international expert panel reached consensus on the definition, screening, clinical management, and timing of delivery in vasa previa, which could inform the development of new clinical guidelines.

National and international guidelines on the management of twin pregnancies: a comparative review.

Twin gestations are associated with increased risk of pregnancy complications. However, high-quality evidence regarding the management of twin pregnancies is limited, often resulting in inconsistencies in the recommendations of various national and international professional societies. In addition, some recommendations related to the management of twin gestations are often missing from the clinical guidelines dedicated to twin pregnancies and are instead included in the practice guidelines on specific pregnancy complications (eg, preterm birth) of the same professional society. This can make it challenging for care providers to easily identify and compare recommendations for the management of twin pregnancies. This study aimed to identify, summarize, and compare the recommendations of selected professional societies from high-income countries on the management of twin pregnancies, highlighting areas of both consensus and controversy. We reviewed clinical practice guidelines of selected major professional societies that were either specific to twin pregnancies or were focused on pregnancy complications or aspects of antenatal care that may be relevant for twin pregnancies. We decided a priori to include clinical guidelines from 7 high-income countries (United States, Canada, United Kingdom, France, Germany, and Australia and New Zealand grouped together) and from 2 international societies (International Society of Ultrasound in Obstetrics and Gynecology and the International Federation of Gynecology and Obstetrics). We identified recommendations regarding the following care areas: first-trimester care, antenatal surveillance, preterm birth and other pregnancy complications (preeclampsia, fetal growth restriction, and gestational diabetes mellitus), and timing and mode of delivery. We identified 28 guidelines published by 11 professional societies from the 7 countries and 2 international societies. Thirteen of these guidelines focus on twin pregnancies, whereas the other 16 focus on specific pregnancy complications predominantly in singletons but also include some recommendations for twin pregnancies. Most of the guidelines are recent, with 15 of the 29 guidelines published over the past 3 years. We identified considerable disagreement among guidelines, primarily in 4 key areas: screening and prevention of preterm birth, using aspirin to prevent preeclampsia, defining fetal growth restriction, and the timing of delivery. In addition, there is limited guidance on several important areas, including the implications of the "vanishing twin" phenomenon, technical aspects and risks of invasive procedures, nutrition and weight gain, physical and sexual activity, the optimal growth chart to be used in twin pregnancies, the diagnosis and management of gestational diabetes mellitus, and intrapartum care.This consolidation of key recommendations across several clinical practice guidelines can assist healthcare providers in accessing and comparing recommendations on the management of twin pregnancies and identifies high-priority areas for future research based on either continued disagreement among societies or limited current evidence to guide care.

Maternal Morbidity with Repeated Cesarean Deliveries.

OBJECTIVE: This study aimed to estimate the association between adverse maternal outcomes and the number of repeated cesarean deliveries (CDs) in a single obstetrical practice. STUDY DESIGN: Retrospective cohort study of all CDs between 2005 and 2020 in a single maternal fetal medicine practice. We used electronic records to get baseline characteristics and pregnancy/surgical outcomes based on the number of prior CDs. We performed two subgroup analyses for women with and without placenta previa. Chi-square for trend and one-way analysis of variance (ANOVA) were used. RESULTS: A total of 3,582 women underwent CD and met inclusion criteria. Of these women, 1,852 (51.7%) underwent their first cesarean, 950 (26.5%) their second, 382 (10.7%) their third, 191 (5.3%) their fourth, 117 (3.3%) their fifth, and 84 (2.3%) their sixth or higher CDs. The incidence of adverse outcomes (placenta accreta, uterine window, uterine rupture, hysterectomy, blood transfusion, cystotomy, bowel injury, need for a ventilator postpartum, intensive care unit admission, wound complications, thrombosis, reoperation, and maternal death) increased with additional CDs. However, the absolute rates remained low. In women without a placenta previa, the likelihood of adverse outcome did not differ across groups. In women with a placenta previa, adverse outcomes increased with increasing CDs. However, the incidence of placenta previa did not increase with increasing CDs (<5% in each group). The incidence of a uterine dehiscence increased significantly with additional CDs: first, 0.2%; second, 2.0%; third, 6.6%; fourth, 10.3%; fifth, 5.8%; and sixth or higher, 10.4% (p < 0.001). CONCLUSION: Maternal morbidity increases with CDs, but the absolute risks remain low. For women without placenta previa, increasing CDs is not associated with maternal morbidity. For women with placenta previa, risks are highest, but the incidence of placenta previa does not increase with successive CDs. The likelihood of uterine dehiscence increases significantly with increasing CDs which should be considered when deciding about timing of delivery in this population. KEY POINTS: · Maternal morbidity increase with each CD.. · Absolute adverse outcomes remains low in highest order CDs.. · In women without placenta previa, there is no added morbidity with additional CDs..

Is Increasing Parity Associated with Adverse Perinatal Outcomes in Dichorionic Twin Gestations?

OBJECTIVE: Dichorionic twins have increased risk of preterm birth and hypertensive disorders of pregnancy. Grand multiparity may be associated with adverse perinatal outcomes in singleton pregnancies, although the effect of increasing parity in twins is unclear. This study aimed to elucidate whether grand multiparity leads to adverse outcomes in dichorionic twins compared with multiparity and nulliparity. STUDY DESIGN: This was a retrospective review of dichorionic twins at a single institution between January 2008 and December 2019 comparing pregnancy outcomes among grand multiparity, multiparity, and nulliparity. Primary outcome was preterm birth less than 37 weeks. Multivariable regression controlled for differing demographics, prior preterm birth, use of reproductive technologies, and hypertensive disorders of pregnancy. Chi square and Fisher's exact were used for categorical variables and Kruskal-Wallis was used for continuous variables. RESULTS: A total of 843 (60.3%) pregnancies were nulliparous, 499 (35.7%) multiparous, and 57(4.1%) grand multiparous. Univariate analysis indicated that multiparous women had lower incidence of preterm birth less than 37, 34, and 32 weeks (57 vs. 51%, p = 0.04; 19.2 vs. 14.0%, p = 0.02; 9.6 vs. 5.6%, p = 0.01) and that grand multiparous women had lower incidence of preterm birth less than 34 weeks (19.2 vs. 5.3%, p = 0.008) compared with nulliparous women. Multivariable regression confirmed multiparous women had lower odds of preterm birth less than 34 and 32 weeks compared with nulliparous women (<34 wk: odds ratio [OR] = 0.69, 95% confidence interval [CI] = 0.49-0.97, p = 0.03; <32 wk: OR = 0.48, 95% CI = 0.29-0.79, p = 0.004) and that multiparous women (OR = 0.57, 95% CI = 0.42-0.77, p = 0.0002) and grand multiparous women (OR = 0.23, 95% CI = 0.08-0.68, p = 0.0074) had lower incidence of hypertensive disorders of pregnancy when compared with nulliparous women. CONCLUSION: Grand multiparity is not associated with adverse perinatal outcomes compared with nulliparity or multiparity in dichorionic twins. Increasing parity may protect against incidence of preterm birth and hypertensive disorders of pregnancy even among grand multiparous women. KEY POINTS: · Incidence of preterm birth may decrease with increasing parity in twins.. · Hypertensive disorders of pregnancy may decrease with increasing parity in twins.. · Grand multiparity is not associated with adverse perinatal outcomes in twins..

Outcomes of Elective Compared to Non-Elective Fetal Reduction by Radiofrequency Ablation in Monochorionic Multifetal Pregnancies.

INTRODUCTION: Higher order fetal gestation is associated with adverse pregnancy outcomes, and monochorionic (MC) pregnancies have unique complications. Multifetal pregnancy reduction (MPR) by radiofrequency ablation (RFA) may be used to optimize the outcomes of a single fetus. The purpose of this study was to determine whether pregnancy outcomes differ for elective reduction compared to reduction for medically complicated MC multifetal pregnancies. METHODS: This was a retrospective cohort of patients with MC twins and higher order multiples who underwent MPR via RFA at a single institution between 2008 and 2021. Patients undergoing elective reduction were compared to patients undergoing reduction due to a complication of MC pregnancy. Pregnancy outcomes were evaluated. RESULTS: Forty-eight patients who underwent RFA reduction between 2008 and 2021 were included in the analysis. Sixteen patients (33.3%) underwent elective RFA for MPR, and 32 (66.7%) underwent an RFA procedure for a complicated pregnancy. All pregnancies with RFA performed for elective indication had a continuing pregnancy (live birth rate 100%). There were no reported pregnancy losses within 4 weeks of the procedure when performed for a solely elective indication (n = 0) compared to 6.3% of complicated multifetal pregnancy (n = 2; 6.3%) (p = 0.001). CONCLUSION: In this retrospective cohort study, elective reduction of MC twins using RFA was associated with no cases of fetal loss or PPROM within 4 weeks of the procedure and a 100% live birth rate.

Should twin-specific growth charts be used to assess fetal growth in twin pregnancies?

One of the hallmarks of twin pregnancies is the slower rate of fetal growth when compared with singleton pregnancies during the third trimester. The mechanisms underlying this phenomenon and whether it represents pathology or benign physiological adaptation are currently unclear. One important implication of these questions relates to the type growth charts that should be used by care providers to monitor growth of twin fetuses. If the slower growth represents pathology (ie, intrauterine growth restriction caused uteroplacental insufficiency), it would be preferable to use a singleton growth chart to identify a small twin fetus that is at risk for perinatal mortality and morbidity. If, however, the relative smallness of twins is the result of benign adaptive mechanisms, it is likely preferable to use a twin-based charts to avoid overdiagnosis of intrauterine growth restriction in twin pregnancies. In the current review, we addressed this question by describing the differences in fetal growth between twin and singleton pregnancies, reviewing the current knowledge regarding the mechanisms responsible for slower fetal growth in twins, summarizing available empirical evidence on the diagnostic accuracy of the 2 types of charts for intrauterine growth restriction in twin pregnancies, and addressing the question of whether uncomplicated dichorionic twins are at an increased risk for fetal death when compared with singleton fetuses. We identified a growing body of evidence that shows that the use of twin charts can reduce the proportion of twin fetuses identified with suspected intrauterine growth restriction by up to 8-fold and can lead to a diagnosis of intrauterine growth restriction that is more strongly associated with adverse perinatal outcomes and hypertensive disorders than a diagnosis of intrauterine growth restriction based on a singleton-based chart without compromising the detection of twin fetuses at risk for adverse outcomes caused by uteroplacental insufficiency. We further found that small for gestational age twins are less likely to experience adverse perinatal outcomes or to have evidence of uteroplacental insufficiency than small for gestational age singletons and that recent data question the longstanding view that uncomplicated dichorionic twins are at an increased risk for fetal death caused by placental insufficiency. Overall, it seems that, based on existing evidence, the of use twin charts is reasonable and may be preferred over the use of singleton charts when monitoring the growth of twin fetuses. Still, it is important to note that the available data have considerable limitations and are primarily derived from observational studies. Therefore, adequately-powered trials are likely needed to confirm the benefit of twin charts before their use is adopted by professional societies.

Clinician-reported chorionicity and zygosity assignment using single-nucleotide polymorphism-based cell-free DNA: Lessons learned from 55,344 twin pregnancies.

OBJECTIVE: Prenatal chorionicity assessment relies on ultrasound, which can be confounded by many factors. Noninvasive assessment of zygosity is possible using single nucleotide polymorphism (SNP)-based cell-free DNA testing. Our objective was to determine the relationship between provider-reported chorionicity and SNP-cfDNA assignment of twin zygosity. METHODS: All twin pregnancy blood samples received by a reference laboratory between September 27, 2017 and September 8, 2021 were included. Chorionicity assignment was requested on the requisition, recorded as; monochorionic (MC), dichorionic, or "don't know". SNP-cfDNA zygosity results, monozygotic (MZ) or dizygotic (DZ), were correlated with chorionicity assignment. RESULTS: 59,471 twin samples (median gestational age = 12.0 weeks at draw) were received and analyzed; 55,344 (93.1%) received zygosity assignment. SNP-cfDNA reported 16,673 (30.1%) MZ and 38,671 (69.9%) as DZ. Provider-reported chorionicity was compared to the zygosity assignment for each case. Of 6283 provider-reported MC twins, 318 (5.1%) were reported as DZ using SNP-cfDNA. CONCLUSION(S): One in 20 suspected MC twin pregnancies were reported as DZ using SNP-cfDNA. Approximately 30% of 55,344 twin pregnancies were found to be MZ, including cases where chorionicity was unknown. SNP-cfDNA zygosity assessment is a useful adjunct assessment for twin pregnancies, particularly those reported as MC or without determined chorionicity.

Non-invasive prenatal testing in the management of twin pregnancies.

Twin pregnancies are common and associated with pregnancy complications and adverse outcomes. Prenatal clinical management is intensive and has been hampered by inferior screening and less acceptable invasive testing. For aneuploidy screening, meta-analyses show that non-invasive prenatal testing (NIPT) through analysis of cell-free DNA (cf-DNA) is superior to serum and ultrasound-based tests. The positive predictive value for NIPT is driven strongly by the discriminatory power of the assay and only secondarily by the prior risk. Uncertainties in a priori risks for aneuploidies in twin pregnancies are therefore of lesser importance with NIPT. Additional information on zygosity can be obtained using NIPT. Establishing zygosity can be helpful when chorionicity was not reliably established early in pregnancy or where the there is a concern for one versus two affected fetuses. In dizygotic twin pregnancies, individual fetal fractions can be measured to ensure that both values are satisfactory. Vanishing twins can be identified by NIPT. Although clinical utility of routinely detecting vanishing twins has not yet been demonstrated, there are individual cases where cf-DNA analysis could be helpful in explaining unusual clinical or laboratory observations. We conclude that cf-DNA analysis and ultrasound have synergistic roles in the management of multiple gestational pregnancies.

The Association between Placental Histopathology, Fetal Growth Restriction, and Preeclampsia in Twin Pregnancies.

OBJECTIVE: This study aims to estimate the association between abnormal placental histopathology, fetal growth restriction (FGR), and preeclampsia (PEC) in twin pregnancies. STUDY DESIGN: Retrospective cohort study of women with diamniotic twin pregnancies with live births at ≥24 weeks of gestation and available placental pathology. Findings were compared between women with and without FGR, which was defined as a birthweight <10th percentile, using singleton and twin growth curves, and those with and without PEC. The primary study outcome was a composite of abnormal placental histopathology. Chi-square, Fisher's exact, and Student's t-tests were used for analysis. RESULTS: Among 859 patients with diamniotic twins, 806 (93.8%) had placental pathology. A total of 422 (52.4%) women had at least one twin with FGR, using a singleton growth curve. FGR affected 136 (16.9%) pregnancies when a twin growth curve was applied. There was no significant difference in composite outcome between groups, using either growth curve (45.5 vs. 44.8%, p = 0.84; adjusted odds ratio (aOR): 1.06, 95% CI: 0.79-1.40 and 52.2 vs. 43.7%, p = 0.07; aOR: 1.44, 95% CI: 0.90-2.10). A total of 122 of 789 (15.5%) patients developed PEC. There was no significant difference in composite outcome between patients with and without PEC (41.8 vs. 45.4%, p = 0.46; aOR: 0.79, 95% CI: 0.53-1.18). CONCLUSION: In twin pregnancies, FGR and PEC are not associated with abnormal placental histopathology. This suggests that the pathologic placental manifestations of these conditions may differ in twins and include factors other than those commonly described in singletons.

Arcuate Uterus as an Independent Risk Factor for Adverse Pregnancy Outcomes.

OBJECTIVE: The aim of the study is to estimate the association between arcuate uterus and pregnancy outcomes using controls selected from a similarly high-risk cohort. STUDY DESIGN: This is a retrospective cohort study of women with an arcuate uterus cared for by a single maternal-fetal medicine practice from 2005 to 2020. We included all women with a singleton pregnancy ≥20 weeks and diagnosis of arcuate uterus and randomly selected (3:1) patients with a singleton pregnancy and no uterine anomaly from the same practice as controls. Baseline characteristics and pregnancy outcomes were compared between the two groups. Chi-square, Fisher's exact, and independent samples t-test were used for data analysis, as indicated. RESULTS: A total of 37 women with an arcuate uterus (55 independent singleton pregnancies) and 165 controls were included. There were no differences in baseline characteristics. Women with an arcuate uterus had a significantly higher rate of spontaneous preterm birth less than 37 weeks (10.9 vs. 3.0%, p = 0.031) and were more likely to require vaginal progesterone (5.5 vs. 0.6%, p = 0.049) and administration of antenatal corticosteroids (16.4 vs. 5.5%, p = 0.020). Arcuate uterus was also associated with lower birthweight (3,028.1 ± 528.0 vs. 3257.2 ± 579.9 g, p = 0.010) and higher incidence of intrauterine fetal growth restriction (20.0 vs. 7.3%, p = 0.008), despite similar starting body mass index (BMI) and weight gain throughout pregnancy. There were no differences in preeclampsia, malpresentation, cesarean delivery, blood transfusion, retained placenta, or morbidly adherent placenta. CONCLUSION: Arcuate uterus is associated with a significantly increased risk of spontaneous preterm birth (<37 weeks), need for vaginal progesterone for short cervix and antenatal corticosteroids, fetal growth restriction, and lower mean birthweight. These findings suggest that arcuate uterus is not just a normal variant of uterine anatomy but rather a risk factor for poor fetal growth, short cervix, and a higher risk pregnancy. KEY POINTS: · Arcuate uterus is associated with increased risk of preterm birth and fetal growth restriction.. · Women with arcuate uteri had higher rates of vaginal progesterone use during pregnancy.. · Arcuate uterus should be treated as a true finding rather than a normal anatomical variant..

Serial Cervical Length Evaluation in Low-Risk Women with Shortened Cervical Lengths in the Midtrimester: How Many Will Dilate Prior to 24 Weeks?

OBJECTIVE: To determine what proportion of women with a short cervical length (CL) without a history of spontaneous preterm birth (SPTB) will ultimately be dilated at <24 weeks. STUDY DESIGN: This is a retrospective cohort study of women with singleton pregnancies with a short CL (≤25 mm) between 16 and 22 weeks' gestational age (GA). We excluded women with a history of SPTB. We examined the progression of women with short CL based on the CL measurement and GA at diagnosis. The primary outcome was cervical dilation or spontaneous delivery <24 weeks. RESULTS: A total of 163 women were included, of whom 27 (16.6%) were ultimately dilated and 4 (2.5%) had pregnancy loss by 24 weeks. The median GA at diagnosis of short CL was 195/7 (range: 15-22) weeks. Women with a CL <15 mm were more likely to have cervical dilation or loss prior to 24 weeks than women whose CL was 15 to 25 mm (42.5 vs. 11.9%, <0.001, adjusted odds ratio: 3.72, 95% confidence interval: 1.52-9.09). GA at diagnosis was not associated with risk of progression. CONCLUSION: In women with a short CL without a history of SPTB, the risk of dilation or pregnancy loss <24 weeks is significant, approaching 50% for women with a CL <15 mm.

Induction of Labor versus Cesarean Delivery in Twin Pregnancies.

OBJECTIVE: This study was aimed to compare maternal and neonatal outcomes between women with twin pregnancies who underwent induction of labor with those women who had planned Cesarean delivery (CD). STUDY DESIGN: This is a retrospective cohort study of women with twin pregnancies ≥ 24 weeks with an indication for delivery but not in labor. Two groups were examined, women who underwent induction and women who underwent planned CD. Maternal and neonatal outcomes were compared between groups both for deliveries at gestational age ≥ 37 weeks and < 37 weeks. RESULTS: A total of 453 patients were included. Overall, 212 (46.8%) women underwent induction and 241 (53.2%) underwent planned CD. Women who underwent induction of labor had a high rate of VD, both in the term and preterm groups (69.8 and 73.6%, respectively). Women who underwent induction of labor had reduced maternal length of stay, neonatal length of stay, and blood loss, without any increase in adverse outcomes. Neonatal ventilation of either twin delivered < 37 weeks was higher in the CD compared with induction group (27.5 vs. 9.4%, p < 0.01), but this was not significant on adjusted odds ratio analysis (aOR = 0.71, 95% CI: 0.19-2.66). CONCLUSION: Labor induction in twin gestations have improved maternal outcomes and similar neonatal outcomes compared with planned CD.

A Case Report to Assess Passive Immunity in a COVID Positive Pregnant Patient.

INTRODUCTION: Data regarding transplacental passage of maternal coronavirus disease 2019 (COVID-19) antibodies and potential immunity in the newborn is limited. CASE REPORT: We present a 25-year-old multigravida with known red blood cell isoimmunization, who was found to be COVID-19 positive at 27 weeks of gestation while undergoing serial periumbilical blood sampling and intrauterine transfusions. Maternal COVID-19 antibody was detected 2 weeks after positive molecular testing. Antibodies were never detected on cord blood samples from two intrauterine fetal cord blood samples as well as neonatal cord blood at the time of delivery. CONCLUSION: This case demonstrates a lack of passive immunity of COVID-19 antibodies from a positive pregnant woman to her fetus, neither in utero nor at the time of birth. Further studies are needed to understand if passage of antibodies can occur and if that can confer passive immunity in the newborn. KEY POINTS: · Passive immunity should not be assumed in COVID-19 infection in pregnancy.. · Isoimmunization may impair passive immunity of certain antibodies.. · Vaccination to or maternal infection of COVID-19 may not be protective for the fetus..

Frequency of spontaneous resolution of vasa previa with advancing gestational age.

BACKGROUND: Vasa previa is a serious obstetric complication that can result in fetal hemorrhage and death on spontaneous labor. Suggested management for vasa previa is elective hospitalization and cesarean delivery before spontaneous labor. There is little reported evidence of the rate of vasa previa resolution over the course of gestation. Identification of the resolution rate and of factors predictive of resolution potentially could improve clinical management and patient counseling. OBJECTIVE: The purpose of this study was to identify the resolution rate of vasa previa across gestation and to determine clinical and sonographic factors that are associated with vasa previa resolution. STUDY DESIGN: We conducted a retrospective cohort study of all women who were diagnosed with vasa previa in a single ultrasound unit between 2005 and 2018. Vasa previa was defined as a fetal vessel within 2 cm of the internal cervical os on transvaginal sonography. The primary outcome was vasa previa resolution, defined as migration of the vasa previa to >2 cm away from the internal os. RESULTS: One hundred women with vasa previa that had been diagnosed at a mean gestational age of 22.8±4.9 weeks were included. Thirty-nine women (39.0%; 95% confidence interval, 30-49%) had resolution of vasa previa at a mean gestational age of 28.6-4.7 weeks. Factors that were associated with vasa previa resolution were an earlier gestational age at diagnosis (adjusted odds ratio, 6.10; 95% confidence interval,1.92-19.40), vasa previa did not cover the internal os at diagnosis (adjusted odds ratio, 8.29; 95% confidence interval, 2.79-24.62), and vasa previa was not the result of a resolved placenta previa (adjusted odds ratio, 2.85; 95% confidence interval, 1.01--8.03). One woman with a dichorionic twin pregnancy and vasa previa resolution (at 31 weeks gestation; fetal vessels located 2.8 cm from the internal os) presented at 33 weeks with massive bleeding and fetal death of twin A. It was unclear whether the death was related to vasa previa or placental abruption. CONCLUSION: Thirty-nine percent of vasa previas in our population resolved over the course of pregnancy. Earlier gestational age at diagnosis, vasa previa not covering the internal os, and not having a resolved placenta previa all are associated independently with an increased likelihood of vasa previa resolution. Women with vasa previa should be observed serially to assess for vasa previa resolution, because many will resolve in the third trimester.

Minimally Invasive Treatment of Cesarean Scar and Cervical Pregnancies Using a Cervical Ripening Double Balloon Catheter: Expanding the Clinical Series.

The efficacy of treating cesarean scar pregnancies and cervical pregnancies with the Cook® cervical ripening balloon catheter, in a multicenter office-based setting is reported. Thirty-eight women were treated. Insertion of the catheter was performed under real-time ultrasound guidance. Patients received adjuvant systemic methotrexate, prophylactic oral antibiotics, and oral pain medication. Serum human chorionic gonadotropin and ultrasound scans were followed serially until resolution. Thirty-seven patients were successfully treated, requiring no further procedures. We found that the Cook cervical ripening balloon technique is a simple, effective, outpatient, minimally invasive treatment with few complications noted in this expanded series.

The Association between Intended Mode of Delivery and Maternal Morbidity in Twin Pregnancies.

OBJECTIVE: To compare maternal morbidity between women undergoing delivery of twins who intend to labor with those women who do not intend to labor. STUDY DESIGN: This was a retrospective cohort study of women undergoing delivery of twins in a single maternal-fetal medicine practice between January 2005 and February 2018. We identified women with a twin delivery at gestational age ≥24 weeks and determined if they intended or did not intend to labor. Maternal outcomes were compared between the groups. RESULTS: A total of 788 patients were included, of whom 404 (51.3%) intended to labor and 384 (48.7%) did not intend to labor. Women who intended to labor had a high rate of vaginal delivery (VD; 79.7%). Overall, 45 (5.7%) women required blood transfusion; this was not significantly different between the groups (6.2 vs. 5.2%, p = 0.54). Women who intended to labor had a shorter hospital stay and lower blood loss. There were no significant differences for all other maternal outcomes. CONCLUSION: In patients undergoing twin delivery, women who intend to labor have similar maternal morbidity compared with women who do not intend to labor. This supports current guidelines recommending providers offer a trial of VD for twin pregnancies.

Time to Delivery after Scheduled Shirodkar Cerclage Removal in Singleton Gestations based on the Original Indication for Cerclage Placement.

OBJECTIVE: To estimate the time to delivery after elective cerclage removal and evaluate whether there is a difference based on the indication for cerclage placement. STUDY DESIGN: This was a retrospective cohort of singleton pregnancies that underwent Shirodkar cerclage placement at a single maternal-fetal medicine practice between June 2005 and June 2017. We included all scheduled elective cerclage removals >36 weeks. The primary outcome was latency to delivery. We further compared time to delivery based on the original indication for cerclage. Data were analyzed using the one-way analysis of variance and chi-square test. RESULTS: A total of 143 patients met the inclusion criteria. Of these, 40.6% were history indicated, 51.0% ultrasound indicated, and 8.4% exam indicated. The mean time from removal to delivery was 13.3 ± 8.4 days; 12.6% (18/136) of patients delivered within 24 hours of removal. When stratified by indication for cerclage, there were no significant differences for all delivery outcomes. Delaying cerclage removal to >37 weeks resulted in a statistically significantly later gestational age at delivery compared with removal between 36 and 366/7 weeks (39.0 vs. 38.3 weeks, p = 0.001). CONCLUSION: The mean time from elective Shirodkar cerclage removal to delivery is 13 days with only 12.6% of patients delivering within 24 hours of removal.

Long-Term Outcomes of Small for Gestational Age Twins Born at 34 Weeks or Later.

OBJECTIVE: This article aims to compare long-term neurodevelopmental and health outcomes of twins born at 34 weeks or later, based on the presence of small for gestational age (SGA). STUDY DESIGN: This study is a mail-based survey of twin gestations delivered by a single practice. We compared twins with and without SGA delivered at ≥34 weeks. There were two primary outcomes for this study: a composite of major adverse outcomes (death; cerebral palsy; necrotizing enterocolitis; chronic renal, heart, or lung disease) and a composite of minor adverse outcomes (learning disability, speech therapy, occupational therapy, physical therapy). Regression analysis was performed to control for clustering of outcomes within twin pairs. RESULTS: A total of 712 children were included. Comparing twins with birthweights <10% to ≥10%, there were no significant differences in rates of composite major morbidities (3.2 vs. 1.4%, p = 0.109) or composite minor morbidities (43.6 vs. 39.3%, p = 0.279). Comparing twins with birthweights <5% to ≥5%, the rates of major morbidities were low in both groups, but significantly higher in the group with birthweights <5% (4.4 vs. 1.6%, p = 0.046). There were no significant differences seen in the composite minor morbidities (46.7 vs. 39.7%, p = 0.134). Twins with birthweights <5% were significantly more likely to have childhood cardiac disease (2.9 vs. 0.7%, p = 0.041). CONCLUSION: Twins with SGA <10% born at ≥34 weeks have similar long-term neurodevelopmental and health outcomes compared with twins with normal birthweights. Birthweight less than 5th percentile is associated with an increased risk of major morbidity, specifically cardiac disease, but the absolute risk is low.

The Association between Fetal Fibronectin, Cervical Length, and Amniotic Fluid Sludge with Histological Indicators of Placental Inflammation in Twin Gestations.

OBJECTIVE: The objective of this study was to evaluate the association of screening tests for preterm birth (short cervical length [CL], positive fetal fibronectin (FFN), and amniotic fluid [AF] sludge) in twin gestations with histologic evidence of placental inflammation. STUDY DESIGN: Historical cohort study of 596 twin gestations delivered in a single maternal-fetal medicine practice with CL and FFN testing from 22 to 256/7 weeks. A short CL was defined as ≤25 mm. Placental lesions evaluated were chronic and acute membrane inflammation and funisitis. Fischer's exact test and logistic regression were used. RESULTS: None of the screening tests was associated with chronic inflammation. All were associated with acute inflammation. On regression analysis, a short CL and positive FFN remained independently associated with acute inflammation (adjusted odds ratio [aOR]: 5.66 and 2.51, respectively) and funisitis (aOR: 5.66 and 7.17, respectively). AF sludge was not independently associated with acute inflammation nor funisitis. CONCLUSION: In twin gestations, a short CL and a positive FFN at 22 to 26 weeks are associated with acute but not chronic inflammation on placental histology. These findings imply that mechanisms underlying preterm birth in twins that result in positive screening tests weeks prior to delivery are not reflected as chronic placental inflammation. Therefore, pathologic interpretation of etiologic mechanisms for preterm birth may be limited using solely histologic reports.