Hypertensive Disease in Twin Pregnancies: A Review

First-trimester uterine artery Doppler and hypertensive disorders in twin pregnancies: Use of twin versus singleton references

OBJECTIVE

To determine the association of first-trimester uterine artery Doppler with hypertensive disorders of pregnancy in twin pregnancies.

METHODS

This was a retrospective cohort study of twin pregnancies followed at the University Hospital Center of Central Lisbon, Portugal, between January 2010 and December 2022. First-trimester uterine artery pulsatility index (UtA-PI) was determined and compared between twin pregnancies (n = 454) and singleton pregnancies (n = 908), matched to maternal and pregnancy characteristics. Maternal characteristics and mean UtA-PI were analyzed for gestational age, birth weight, gestational hypertension, early- and late-onset pre-eclampsia, HELLP (hemolysis, elevated liver enzymes, low platelets) syndrome, and preterm birth. Univariable and multivariable logistic regression models were used.

RESULTS

The mean first-trimester UtA-PI was significantly lower in dichorionic twins than in singletons (P < 0.001). To study hypertensive disorders of pregnancy in twins, 390 pregnancies were included: 311 (79.7%) dichorionic and 79 (20.3%) monochorionic twins. The observed rates of early- and late-onset pre-eclampsia, gestational hypertension, and HELLP syndrome were 1.0%, 4.4%, 7.4%, and 1.5%, respectively. We achieved a 100% detection rate for early-onset pre-eclampsia using the UtA-PI 90th centile for twins. However, when singleton references were considered, the detection rate decreased to 50%. UtA-PI at or above the 95th centile was associated with increased odds for preterm birth before 32 weeks (adjusted odds ratio 4.1, 95% confidence interval 1.0-16.7, P = 0.043).

CONCLUSIONS

Unless other major risk factors for hypertensive disorders are present, women with low UtA-PI will probably not benefit from aspirin prophylaxis. Close monitoring of all twin pregnancies for hypertensive disorders is still recommended.

sFLT1, PlGF, the sFLT1/PlGF Ratio and Their Association with Pre-Eclampsia in Twin Pregnancies-A Review of the Literature

Twin pregnancies demonstrate a 2-3-fold higher chance of developing PE compared to singletons, and recent evidence has demonstrated that the sFLT1/PIGF ratio is strongly associated with PE, adverse pregnancy outcomes, as well as imminent deliveries due to PE complications. The primary objective of this systematic review was to summarise the available data on the levels of sFLT1, PlGF and their ratios in twin pregnancies and to investigate their association with the development of PE, adverse pregnancy outcomes and the timing of the delivery. A systematic search of Ovid Embase, Web of Science, Science Direct, PubMed, Ovid Medline, Google Scholar and CINAHL was carried out. sFLT1 levels and the sFLT1/PIGF ratio appeared higher in twins compared to singleton pregnancies, especially in the third trimester, while PlGF levels appeared higher up until the third trimester, with their values showing no difference or being even lower than in singletons thereafter. The sFLT1/PIGF ratio has been reported to be an independent marker of adverse outcomes related to pre-eclampsia and is associated with the mean time until delivery in an inverse manner. Further research is required in order to establish the optimal sFLT1/PIGF cut-off values and to stratify the risk of adverse outcomes in twin pregnancies.

Association between One Abnormal Value on 3-Hour Oral Glucose Tolerance Test and Adverse Perinatal Outcomes in Twin Gestation

AIM

To investigate whether women with twin gestation and one abnormal value on the diagnostic 3-hour oral glucose tolerance test (OGTT) are at an increased risk of adverse perinatal outcomes.

METHODS

This was a retrospective multicenter study of women with twin gestation, comparing four groups: (1) normal 50-g screening, (2) normal 100-g 3-hour OGTT, (3) one abnormal value on the 3-hour OGTT, and (4) GDM. Multivariable logistic regressions adjusted for maternal age, gravidity, parity, previous CDs, fertility treatments, smoking, obesity and chorionicity were used.

RESULTS

The study included 2,597 women with twin gestations, of which 79.7% had a normal screen, and 6.2% had one abnormal value on the OGTT. In adjusted analyses, women with one abnormal value were found to have higher rates of preterm delivery <32 weeks, large for gestational age neonates, and composite neonatal morbidity of at least one fetus, however, similar maternal outcomes as those with a normal screen.

CONCLUSION

Our study provides evidence that women with twin gestation and one abnormal value on the 3-hour OGTT are at an increased risk of unfavorable neonatal outcomes. This was confirmed by multivariable logistic regressions. Further research is needed to determine whether interventions such as nutritional counseling, blood glucose monitoring, and treatment with diet and medication would improve perinatal outcomes in this population.

Adverse obstetric outcomes in women with PCOS and multiple gestations

RESEARCH QUESTION

Does multiple gestation alter the risks for adverse obstetric outcomes in women with polycystic ovary syndrome (PCOS)?

DESIGN

Retrospective population-based cohort study using data from the HCUP-NIS from 2004 to 2014. A total of 14,882 women with PCOS, who delivered within that time period, were identified. The study group comprised women with PCOS who had had a multiple gestation (n = 880); the reference group was comprised of the remaining women with PCOS and singleton gestation (n = 14,002).

RESULTS

In women with PCOS, multiple gestation increased the risks of pregnancy complications including pregnancy-induced hypertension (adjusted odds ratio [aOR] 2.030; 95% confidence interval [CI] 1.676-2.460), pre-eclampsia (aOR 2.879; 95% CI 2.277-3.639), pre-eclampsia and eclampsia superimposed on pre-existing hypertension (aOR 1.917; 95% CI 1.266-2.903) and gestational diabetes (aOR 1.358; 95% CI 1.114-1.656). Multiple gestation increases the risk of preterm premature rupture of membranes (aOR 5.807; 95% CI 4.153-8.119), preterm delivery (aOR 8.466; 95% CI 7.071-10.135), Caesarean section (aOR 5.146; 95% CI 4.184-6.329), post-partum haemorrhage (aOR 1.540; 95% CI 1.065-2.228) and the need for transfusion (aOR 3.268; 95% CI 2.010-5.314), as well as wound complications (aOR 3.089; 95% CI 1.647-5.794). Neonates born to mothers with PCOS and having multiple gestations are more likely to be small for gestational age when compared to singleton neonates born to mothers with PCOS (aOR 4.606; 95% CI 3.480-6.095). Among PCOS women with multiple gestations, obesity increased the risks of developing pregnancy-induced hypertension (P < 0.001), pre-eclampsia (P < 0.001) and wound complications (P = 0.045).

CONCLUSION

These results highlight the importance of single embryo transfer and ovulation induction to develop a single follicle in women with PCOS. Obesity further increases obstetrical complications.

Long-term cardiovascular mortality in women with twin pregnancies by lifetime reproductive history

BACKGROUND

Women with one lifetime singleton pregnancy have increased risk of cardiovascular disease (CVD) mortality compared with women who continue reproduction particularly if the pregnancy had complications. Women with twins have higher risk of pregnancy complications, but CVD mortality risk in women with twin pregnancies has not been fully described.

OBJECTIVES

We estimated risk of long-term CVD mortality in women with naturally conceived twins compared to women with singleton pregnancies, accounting for lifetime number of pregnancies and pregnancy complications.

METHODS

Using linked data from the Medical Birth Registry of Norway and the Norwegian Cause of Death Registry, we identified 974,892 women with first pregnancy registered between 1967 and 2013, followed to 2020. Adjusted hazard ratios (aHR) with 95% confidence intervals (CI) for maternal CVD mortality were estimated by Cox regression for various reproductive history (exposure categories): (1) Only one twin pregnancy, (2) Only one singleton pregnancy, (3) Only two singleton pregnancies, (4) A first twin pregnancy and continued reproduction, (5) A first singleton pregnancy and twins in later reproduction and (6) Three singleton pregnancies (the referent group). Exposure categories were also stratified by pregnancy complications (pre-eclampsia, preterm delivery or perinatal loss).

RESULTS

Women with one lifetime pregnancy, twin or singleton, had increased risk of CVD mortality (adjusted hazard [HR] 1.72, 95% confidence interval [CI] 1.21, 2.43 and aHR 1.92, 95% CI 1.78, 2.07, respectively), compared with the referent of three singleton pregnancies. The hazard ratios for CVD mortality among women with one lifetime pregnancy with any complication were 2.36 (95% CI 1.49, 3.71) and 3.56 (95% CI 3.12, 4.06) for twins and singletons, respectively.

CONCLUSIONS

Women with only one pregnancy, twin or singleton, had increased long-term CVD mortality, however highest in women with singletons. In addition, twin mothers who continued reproduction had similar CVD mortality compared to women with three singleton pregnancies.

Results of a Five-Year Experience in First Trimester Preeclampsia Screening

Background and Objectives: The study aimed to evaluate the ability defining the risk of developing preeclampsia by a screening test carried out in the first trimester (between 11 + 0 and 13 + 6 weeks of gestational age), in order to identify high-risk women requiring more intensive health surveillance. The secondary objective was to evaluate the ability of this test to predict the risk of adverse obstetric outcomes such as fetal growth restriction, intrauterine fetal death, gestational hypertension, HELLP syndrome, placental abruption, and preterm birth. Materials and Methods: This was a single-center study, conducted at the Operative Unit of Obstetrics of the State Hospital of the Republic of San Marino. Medical history was collected at the time of enrolment in writing. Subsequently, obstetric outcomes were collected for each enrolled woman, through the analysis of medical records. Results: From October 2014 to May 2019, 589 pregnant women were recruited, of whom, 474 (80.5%) were included in the “low-risk” group, and 115 (19.5%) in the “high-risk” group. At the time of analysis of this population, the obstetric outcomes were available for 498 women (84.5%), while 91 cases (15.5%) were current pregnancies. The PI of the uterine arteries was not significantly different between the two study groups. Otherwise, a significant difference was highlighted for MAP, which is higher in the case of pregnancies at high risk based on the risk factors only, and for PAPP-A, higher in the case of low-risk pregnancies. Regarding the percentage of fetal DNA, according to the most recent literature data, in our series, we report a statistically significant difference of the average between the low and high-risk groups. Conclusions: In our study, we demonstrate that the multiparametric screening test for early PE performed well in identifying women at high risk of early PE, which certainly has the most severe maternal–fetal outcomes. The data reported that ASA intake at low doses is significantly higher in the population with high-risk tests for both early PE and late PE suggest once again that anamnestic evaluation plays an essential role in women’s screening.

sFlt-1/PlGF ratio at 24 weeks gestation in twin pregnancies as a predictor of preeclampsia or fetal growth restriction

OBJECTIVE

to elucidate if sFlt-1/PlGF ratio at 24 weeks in twin pregnancies could be useful to select patients who subsequently develop diseases related to placental dysfunction, such as preeclampsia or fetal growth restriction (FGR).

METHODS

prospective study among all twin pregnancies followed up at a tertiary Hospital. The sFlt-1/PlGF ratio was determined at 24 weeks.

RESULTS

a total of 108 patients with a twin gestation were included. Pregnant women who developed preeclampsia and/or FGR displayed a significantly higher sFlt-1/PlGF ratio at 24 weeks, compared to those who did not develop these diseases (20.3 vs 4.3, p=0.002). Mean sFlt-1/PlGF ratio was not significantly different between patients who subsequently developed preeclampsia compared with those that developed FGR (29.8 vs 18.45, p=0.42). An sFlt-1/PlGF ratio ≥17 at 24 weeks is associated with a significant increase in the frequency of preeclampsia (odds ratio, 37.13 [95% confidence interval, 4.78-288.25]; p=0.002), and FGR (odds ratio, 39.58 [95% confidence interval, 6.31-248.17]; p<0.001). The addition of maternal characteristics, and mean pulsatility index of the uterine arteries to the sFlt-1/PlGF ratio at 24 weeks enhance the identification of patients who develop preeclampsia or FGR.

CONCLUSION

sFlt-1/PlGF ratio at 24 weeks in twin pregnancies, combined with mean pulsatility index of the uterine arteries and maternal characteristics, could select patients who develop preeclampsia or FGR. These patients might benefit from a close follow-up in order to avoid maternal-fetal adverse outcomes.

Screening for preeclampsia in twin pregnancies

Twin pregnancies are an important risk factor for preeclampsia, a hypertensive disorder of pregnancy that is associated with a significant risk of maternal and perinatal morbidity. Given the burden of preeclampsia, the identification of women at high risk in early pregnancy is essential to allow for preventive strategies and close monitoring. In singleton pregnancies, the risk factors for preeclampsia are well established, and a combined first-trimester prediction model has been shown to adequately predict preterm disease. Furthermore, intervention with low-dose aspirin at 150 mg/day in those identified as high-risk reduces the rate of preterm preeclampsia by 62%. In contrast, risk factors for preeclampsia in twin pregnancies are less established, the proposed screening models have shown poor performance with high false-positive rates, and the benefit of aspirin for the prevention of preeclampsia is not clearly demonstrated. In this review, we examine the literature assessing prediction and prevention of preeclampsia in twin pregnancies.

Outcomes Associated With Hypertensive Disorders of Pregnancy in Twin Compared With Singleton Gestations

OBJECTIVE

To evaluate whether pregnancy outcomes associated with hypertensive disorders of pregnancy in twin pregnancies differ relatively from those in singleton pregnancy.

METHODS

We conducted a retrospective, population-based cohort study of all women with a liveborn singleton or twin hospital birth in Ontario, Canada, between 2012 and 2019. Data were obtained from the Better Outcomes Registry & Network Ontario. Pregnancy outcomes were compared between women with and without hypertensive disorders of pregnancy in twin gestations, and separately in singleton gestations. Adjusted relative risks (aRRs) and 95% CIs were generated using modified Poisson regression and were compared between twins and singletons using relative risk ratios.

RESULTS

Overall, 932,218 women met the study criteria, of whom 917,542 (98.4%) and 14,676 (1.6%) had singleton and twin gestations, respectively. The incidence of hypertensive disorders of pregnancy was higher in women with twin compared with singleton gestations (14.4% vs 6.4%, aRR 1.85 [1.76-1.94]). Hypertensive disorders of pregnancy were associated with certain adverse outcomes in singleton gestations only and with other adverse outcomes in both the singleton and twin gestations, but the aRR was lower in twins. For example, preterm birth before 37 weeks of gestation (singletons: 15.2% [hypertensive disorders of pregnancy] vs 5.4% [no hypertensive disorders of pregnancy], aRR 2.42; twins: 67.5% [hypertensive disorders of pregnancy] vs 50.4% [no hypertensive disorders of pregnancy], aRR 1.30) and neonatal respiratory morbidity (singletons: 16.3% [hypertensive disorders of pregnancy] vs 8.7% [no hypertensive disorders of pregnancy], aRR 1.50; twins: 39.8% [hypertensive disorders of pregnancy] vs 32.7% [no hypertensive disorders of pregnancy], aRR 1.13). These findings persisted in the subgroups of women with preeclampsia and early-onset preeclampsia.

CONCLUSIONS

Although the absolute risk of adverse maternal and neonatal outcomes is higher in twin compared with singleton pregnancies, the incremental risk of adverse outcomes associated with hypertensive disorders in twin pregnancies is lower than the incremental risk in singleton pregnancies. These findings may be attributed in part to the higher baseline risk of preterm birth and adverse maternal and perinatal outcomes in twin compared with singleton pregnancies.

Pregnancy and birth characteristics of Aboriginal twins in two Australian states: a data linkage study

Introduction

Perinatal outcomes for singleton pregnancies are poorer, on average, for Aboriginal people than non-Aboriginal people, but little is known about Aboriginal multifetal pregnancies. Yet multifetal pregnancies and births are often more complicated and have poorer outcomes than singleton pregnancies. We describe the pregnancies, births and perinatal outcomes for Aboriginal twins born in Western Australia (WA) and New South Wales (NSW) with comparisons to Aboriginal singletons in both states and to non-Aboriginal births in NSW.

Materials and methods

Whole-population birth records and birth and death registrations were linked for all births during 2000–2013 (WA) and 2002–2008 (NSW). Hospital records and the WA Register of Developmental Anomalies - Cerebral Palsy were linked for all WA births and hospital records for a subset of NSW births. Descriptive statistics are reported for maternal and child demographics, maternal health, pregnancy complications, births and perinatal outcomes.

Results

Thirty-four thousand one hundred twenty-seven WA Aboriginal, 32,352 NSW Aboriginal and 601,233 NSW non-Aboriginal births were included. Pregnancy complications were more common among mothers of Aboriginal twins than Aboriginal singletons (e.g. 17% of mothers of WA twins had hypertension/pre-eclampsia/eclampsia vs 8% of mothers of singletons) but similar to mothers of NSW non-Aboriginal twins. Most Aboriginal twins were born in a principal referral, women’s or large public hospital. The hospitals were often far from the mother’s home (e.g. 31% of mothers of WA Aboriginal twins gave birth at hospitals located more than 3 h by road from their home). Outcomes were worse for Aboriginal liveborn twins than Aboriginal singletons and non-Aboriginal twins (e.g. 58% of NSW Aboriginal twins were preterm compared to 9% of Aboriginal singletons and 49% non-Aboriginal twins).

Conclusions

Mothers of Aboriginal twins faced significant challenges during the pregnancy, birth and the postnatal period in hospital and, in addition to accessible specialist medical care, these mothers may need extra practical and psychosocial support throughout their journey.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-03945-9.

A Review of Research Progress of Pregnancy with Twins with Preeclampsia

Preeclampsia has a significant long-term effect on the health of both mothers and babies. Preeclampsia-related pregnancy complications increase the morbidity and mortality of pregnant women and their fetuses by 5-8%. The recent advancement of assisted reproductive technology, combined with a rise in the number of elderly pregnant women, has resulted in pregnancy incidence with twins. Twins pregnant women have a 2-3 times greater risk of developing preeclampsia than singleton pregnant women, and it happens sooner and progresses faster. It is more severe and may appear in an atypical way. End-organ damage, such as renal failure, stroke, cardiac arrest, pulmonary edema, placental abruption, and cesarean section, are related maternal complications. Fetal growth retardation, stillbirth, and premature delivery with obstetric signs are all fetal complications. According to studies, all multiple pregnancies can take low-dose aspirin (60-150 mg) to minimize the risk of preeclampsia. To improve pregnancy outcomes and reduce the inherent risk of pregnancy with twins, twins should be handled as a high-risk pregnancy and treated differently than singletons. The literature on twin pregnancy with preeclampsia is the subject of this review. It will examine the current state of research on preeclampsia in pregnancy with twins, including the occurrence, diagnosis, and pathophysiological process. Moreover, the effect of pregnancy with twins on the perinatal outcome and pregnancy management of pregnancy with twins, including blood pressure management and preeclampsia prevention and treatment, is examined in this literature review. The goal is to figure out what kind of diagnosis and care you may need.

Gestational Weight Gain in Twin Pregnancies and Maternal and Child Health: An Updated Systematic Review

Background: The Institute of Medicine (IOM) has provisional gestational weight gain (GWG) guidelines for women pregnant with twins due to limited data in this population. To better inform guidelines, the objective of this systematic review was to build on prior work and examine recent data on the associations of GWG with maternal and child health in twin pregnancies. Materials and Methods: In February 2021, Ovid MEDLINE, Embase, CINAHL, and Cochrane Library were searched. Observational studies were eligible if published from January 1, 2013 through February 23, 2021, and examined associations of GWG with maternal or child health outcomes after accounting for gestational age at delivery and pre-pregnancy body mass index. Heterogeneity across studies precluded the use of meta-analytic methods. Results: A total of 29 studies were included. For maternal outcomes, excessive GWG was associated with an increased risk of hypertensive disorders of pregnancy; whereas studies examining gestational diabetes and delivery method reported mixed findings. For child outcomes, inadequate GWG was associated with lower birthweight, small for gestational age, and preterm birth. Adequate or excessive GWG was associated with later gestational age at delivery. Conclusions: This study advances an earlier review by including a more diverse array of maternal and child outcomes. Many of the limitations noted in the original review persist; for example, no studies examined the associations of GWG and outcomes beyond birth. Although it appears that GWG within the IOM guidelines is associated with more optimal outcomes, additional methodologically rigorous studies are needed to better inform evidence-based guidelines.

Gestational Age-Specific Reference Ranges for the sFlt-1/PlGF Immunoassay Ratio in Twin Pregnancies

OBJECTIVE

Establish reference ranges for the Elecsys® soluble fms-like tyrosine kinase-1 (sFlt-1)/placental growth factor (PlGF) immunoassay ratio in twin pregnancies.

METHODS

Data analyzed were from 3 prospective studies: Prediction of Short-Term Outcome in Pregnant Women with Suspected Preeclampsia (PE) (PROGNOSIS), Study of Early-onset PE in Spain (STEPS), and a multicenter case-control study. Median, 5th, and 95th percentiles for sFlt-1, PlGF, and the sFlt-1/PlGF ratios were determined for normal twin pregnancies for 7 gestational windows and compared with the previous data for singleton pregnancies.

RESULTS

The reference range analysis included 269 women with normal twin pregnancies. Before 29 weeks' gestation, median, 5th, and 95th percentiles for sFlt-1/PlGF ratios did not differ between twin and singleton pregnancies. From 29 weeks' gestation to delivery, median, 5th, and 95th percentiles for sFlt-1/PlGF ratios were substantially higher in twin versus singleton pregnancies. sFlt-1 values were higher in women with twin pregnancies across all gestational windows. PlGF values were similar or higher in twin versus singleton pregnancies; PlGF concentrations increased from 10 weeks + 0 days to 28 weeks + 6 days' gestation.

CONCLUSIONS

Reference ranges for the sFlt-1/PlGF ratio are similar in women with twin and singleton pregnancies until 29 weeks' gestation but appear higher in twin pregnancies thereafter.

Prediction of adverse perinatal outcome and the mean time until delivery in twin pregnancies with suspected pre-eclampsia using sFlt-1/PIGF ratio

PURPOSE

An elevated soluble fms-like tyrosine kinase-1 (sFlt-1) / placental growth factor (PlGF) ratio is associated with adverse perinatal outcome (APO) and the mean time until delivery (MTUD) in singleton pregnancies complicated by pre-eclampsia (PE). Data on APO and MTUD prediction in twin pregnancies using sFlt-1/PlGF ratio are scarce. We evaluated the predictive value of the sFlt-1/PIGF ratio regarding APO and MTUD in twin pregnancies with suspected PE and/or HELLP syndrome.

METHODS

This is a single center retrospective cohort study. All twin pregnancies with suspected PE/HELLP and determined sFlt-1/PIGF were included. Composite APO (CAPO) was defined as the presence of at least one of the following outcomes: respiratory distress syndrome (RDS), intubation, admission to neonatal intensive care unit (NICU) and arterial umbilical cord pH value < 7.10. Selective fetal growth restriction (s-FGR) was analyzed separately.

RESULTS

For final analysis, 49 twin pregnancies were included. Median sFlt-1/PIGF ratio was not significantly different in patients with CAPO compared to those without (89.45 vs. 62.00, p = 0.669). MTUD was significantly negative correlated with sFlt-1/PIGF ratio (r = -0.409, p < 0.001). For the whole study cohort, ROC analysis revealed no predictive value for sFlt-1/PIGF and CAPO (AUC = 0.618, 95% CI: 0.387-0.849, p = 0.254). However, sFlt-1/PIGF ratio showed a predictive value for s-FGR (AUC = 0.755, 95% CI: 0.545-0.965, p = 0.032).

CONCLUSION

In twin pregnancies with PE and/or HELLP, sFlt-1/PIGF ratio may be helpful for s-FGR prediction and decision-making regarding close monitoring of high-risk patients. However, further prospective studies are warranted to define the role of sFlt-1/PlGF ratio as outcome predictor in twin pregnancies.

Notching and Pulsatility Index of the Uterine Arteries and Preeclampsia in Twin Pregnancies

Increased uterine artery Doppler indices have been shown to be associated with preeclampsia and adverse pregnancy outcomes in singleton and twin pregnancies. At 20–22 weeks of gestation, we assessed the use of notching, the highest, lowest, and mean pulsatility index (PI), and the combination of notching and PI of the uterine arteries to screen for preeclampsia. This was done in a cohort of 380 twin pregnancies. The results showed that the combination of notching and the highest PI above the 95th centile of the uterine arteries gives the best screening characteristics for preeclampsia in twin pregnancies. We calculated sensitivities for preeclampsia for notching, highest PI, and the combination of notching and the highest PI of 50%, 45% and 91%, with specificities of 96%, 96% and 93%, respectively. The present findings demonstrate that notching, increased highest PI, and the combination of notching and the highest PI of the uterine arteries is associated with an increased risk of preeclampsia in twin pregnancies. We observed the highest sensitivity and specificity by using the combination of notching and the highest PI of the uterine arteries.

Association of provider advice and gestational weight gain in twin pregnancies: a cross-sectional electronic survey

BACKGROUND

Little is known about patient-provider communication on gestational weight gain among women pregnant with twins, a growing population at high risk for adverse maternal and neonatal outcomes. We examined if women's report of provider advice on gestational weight gain was consistent with the Institute of Medicine (IOM) weight gain guidelines for twin pregnancies, and the association of provider advice on weight gain with women's weight gain during their twin pregnancy.

METHODS

We conducted a cross-sectional survey of 276 women who delivered twins and received prenatal care in the United States. The 2009 IOM provisional weight gain guidelines for twin pregnancies defined whether provider advice on weight gain and women's weight gain were below, within, or above guidelines. Multinomial logistic regression examined associations between provider advice on weight gain with women's weight gain, after adjustment for maternal age, gestational age at delivery, education, parity, twin type, use of assisted reproductive technologies and pre-pregnancy BMI category.

RESULTS

Approximately 30% of women described provider advice on weight gain below the IOM guidelines, 60% within, and 10% above guidelines. Compared to women who reported weight gain advice within guidelines, women who reported advice below guidelines or who reported no advice were 7.1 (95% CI: 3.2, 16.0) and 2.7 (95% CI: 1.3, 5.6) times more likely to gain less than recommended, respectively. Women who reported provider advice above guidelines were 4.6 (95% CI: 1.5, 14.2) times more likely to exceed guidelines.

CONCLUSIONS

Provider advice on gestational weight gain may be an important predictor of women's weight gain during twin pregnancies, highlighting the critical need for accurate provider counseling to optimize health outcomes.

The maternal and perinatal implications of hypertensive disorders of pregnancy in a multiple pregnancy cohort

INTRODUCTION

Hypertensive disorders of pregnancy are common and may result in increased maternal and neonatal morbidity and mortality. Multiple pregnancies confer an increased risk of development of a hypertensive disorder of pregnancy. The purpose of this study was to examine a large cohort of women delivering a multiple pregnancy in a single large tertiary unit, and to evaluate the implications of hypertensive disorders of pregnancy on both maternal and perinatal outcomes.

MATERIAL AND METHODS

Retrospective study of all twin pregnancies delivered at Cork University Maternity Hospital, Ireland over a 9-year period (2009-2017). The twin pregnancies were divided according to the presence or absence of hypertensive disorder of pregnancy and the two groups were compared.

RESULTS

Maternal age >40 years, nulliparity, conception through use of a donor oocyte, and presence of obstetric cholestasis are all risk factors for the development of hypertensive disorders of pregnancy in women with a multiple pregnancy. When a hypertensive disorder complicates a twin pregnancy, it increases the incidence of iatrogenic late prematurity and neonatal hypoglycemia.

CONCLUSIONS

This study is informative for clinicians caring for women with a multiple pregnancy with its relevant data on perinatal outcomes following a diagnosis of hypertensive disorder in pregnancy.

Higher rate of early-onset preeclampsia in pregnancies following oocyte donation according to increasing maternal age

OBJECTIVE

To assess the influence of maternal age on the incidence of early-onset preeclampsia requiring delivery before 34 weeks of gestation in pregnancies obtained after oocyte donation.

METHODS

We carried out a prospective cohort analysis of 431 single and twin pregnancies, admitted to 3 Tertiary Referral Hospital in Northern Italy between 2008 and 2017. The rate of early-onset PE was calculated and stratified according to maternal age (from 30 to 49 years). A reference population of 11,197 single pregnancies collected prospectively at the first trimester of pregnancy in the same geographic area of Italy and in same hospitals was used to calculate the expected incidence of early-onset PE.

RESULTS

In women who delivered after 24 weeks of gestation, the rate of early-onset PE was much higher in oocyte-donation pregnancies, reaching 6.7% (29/431), than the expected rate of 0.5% of the cohort of reference. The mean early PE rate was 4.1% (10/242) in singletons and 10.1% (19/189) in twin pregnancies. According to maternal age, the rate of early PE was 1.16% and 3.12% at 30 years, and 4.98% and 13.14% at 49 years in single and twin pregnancies obtained after oocyte donation, respectively.

CONCLUSION

Pregnancies obtained after oocyte donation delivering after 24 weeks had a higher risk of early-onset PE requiring delivery before 34 weeks of gestation, than the general population. The risk is directly correlated with the increase of maternal age and is also higher in twin pregnancies.

Association between hypertensive disorders and fetal growth restriction in twin compared with singleton gestations

BACKGROUND

Hypertensive disorders of pregnancy (including preeclampsia or gestational hypertension) are associated with fetal growth restriction in singleton pregnancies, an association that may be attributed to abnormal placentation as the shared etiology between these conditions. Given that the pathogenesis of these conditions in twin pregnancies may involve mechanisms other than abnormal placentation, it is unclear whether a similar association between hypertensive disorders of pregnancy and fetal growth restriction is present in twins. Data on the relationship between hypertensive disorders of pregnancy and fetal growth restriction in twins are limited and conflicting. This controversy may be attributed to limitations of existing studies including the use of a singleton-based birthweight reference to define fetal growth restriction in twins and the lack of a positive control group of singleton gestations.

OBJECTIVE

The objective of the study was to determine the association between hypertensive disorders of pregnancy and fetal growth restriction in dichorionic twin gestations, using both a singleton- and a twin-based birthweight reference, and to compare this association with that observed in singleton gestations.

STUDY DESIGN

We performed a retrospective cohort study of all women with dichorionic twin or singleton gestations giving birth in a single tertiary center during 2003-2015. Fetal growth restriction was defined in separate analyses as birthweight <10th percentile for gestational age using either a singleton- or a twin-based birthweight reference. The association between hypertensive disorders of pregnancy and fetal growth restriction was determined separately for twin and singleton gestations and was expressed as adjusted relative risk with 95% confidence interval.

RESULTS

A total of 1520 twin and 48,943 singleton gestations were included. In singleton gestations, hypertensive disorders of pregnancy were associated with an increased risk of fetal growth restriction (16.6% vs 7.4%, adjusted relative risk, 2.07, 95% confidence interval, 1.87-2.30). In twins, there was no association between hypertensive disorders of pregnancy and fetal growth restriction when a singleton-based reference was used to define fetal growth restriction. However, when using a twin-based reference to define fetal growth restriction, hypertensive disorders of pregnancy in twin gestations were associated with a similar increase in the risk of fetal growth restriction to that seen in singletons (11.8% vs 4.7%, adjusted relative risk, 2.37, 95% confidence interval, 1.69-3.34). Findings were similar with regard to the reverse association between fetal growth restriction and hypertensive disorders of pregnancy: in women with twin gestations, the increase in the risk of hypertensive disorders of pregnancy in pregnancies complicated by fetal growth restriction of 1 twin was similar to that observed in singletons only when a twin-based reference was used to define fetal growth restriction (twins: 21.3% vs 9.8%, adjusted relative risk, 2.15, 95% confidence interval, 1.63-3.06; singletons: 8.8% vs 3.7%, adjusted relative risk, 2.19, 95% confidence interval, 1.95-2.44).

CONCLUSION

The association between hypertensive disorders of pregnancy and fetal growth restriction in dichorionic twins is similar in magnitude to that observed in singletons so long as appropriate birthweight references are applied. Therefore, women with a twin gestation complicated by one of these conditions should be closely monitored for the other. Our findings suggest that the use of a twin-based reference to diagnose fetal growth restriction in twin gestations may be more informative and clinically relevant than using a singleton-based reference.

Prevalence and risk of pre-eclampsia and gestational hypertension in twin pregnancies: a population-based register study

OBJECTIVES

The aim of this study was to assess the prevalence and risk of pre-eclampsia and gestational hypertension in twin pregnancies compared with singleton pregnancies.

DESIGN

Population-based cohort study.

SETTING

Medical Birth Registry of Norway and Statistics Norway.

PARTICIPANTS

929 963 deliveries with 16 174 twin pregnancies in 1999-2014.

METHODS

Pre-eclampsia prevalences in twin and singleton pregnancies were described in percentages. Multivariable regression analyses were performed to assess the risks of pre-eclampsia and gestational hypertension in twin pregnancies compared with those in singleton pregnancies, adjusted for previously known risk factors.

PRIMARY AND SECONDARY OUTCOME MEASURES

Prevalence and risk of pre-eclampsia and gestational hypertension.

RESULTS

The prevalence of pre-eclampsia in the study population was 3.7% (3.4% in singleton pregnancies, 11.8% in twin pregnancies (p=0.001)). The OR for pre-eclampsia in twin pregnancies was three to fourfold compared with singleton pregnancies (OR 3.78; 95% CI 3.59 to 3.96). After adjustment for known risk factors, twin pregnancy remained an independent risk factor for pre-eclampsia (adjusted OR 4.07; 95% CI 3.65 to 4.54). The prevalence of gestational hypertension was 1.7% in women with singleton pregnancies and 2.2% in those with twin pregnancies (OR 1.27; 95% CI 1.14 to 1.41). After adjustment for known risk factors, gestational hypertension was not significantly associated with twin pregnancy.

CONCLUSIONS

The risk of pre-eclampsia in twin pregnancies was three to fourfold compared with singleton pregnancies, regardless of maternal age, parity, educational level, smoking, maternal comorbidity or in vitro fertilisation. The risk of gestational hypertension was not increased in women with twin pregnancies after adjustment for the main risk factors.

Ultrasound study of fetal movements in singleton and twin pregnancies at 12-19 weeks

Objective To evaluate fetal behavioral differences between singleton and twin fetuses before 20 weeks of gestation using four-dimensional (4D) ultrasound. Methods 4D ultrasound was used to examine fetal movements in 58 singleton and 48 twin normal fetuses at 12-19 weeks. The frequencies of eight fetal movements were assessed through 15-min recordings. The fetuses were divided into two gestational age groups (12-13 and 14-19 weeks) to evaluate the changes with advancing gestation in twin versus singleton fetuses. Results Arm and general movements were the most frequent movements in singleton fetuses, whereas only general movement was significantly more frequent than the other seven fetal movements in twin fetuses at 12-13 weeks. At 14-19 weeks, frequencies of arm and leg movements were significantly higher than those of the other six movements in singleton fetuses, while only arm movement was significantly more frequent than the other fetal movements in twin fetuses. Comparisons of fetal movements between singleton and twin fetuses revealed that only arm movement showed a significant difference at 12-13 weeks, while the frequencies of all movements in singleton fetuses were significantly higher than those in twin fetuses at 14-19 weeks. Conclusion Our results suggest that the limitation of available space and crowding of twin fetuses with advancing gestation may have a marked impact on twin fetal movements compared with singleton fetuses, even in the first half of pregnancy. Further studies are needed to assess whether decreased fetal movements in twin pregnancy can affect fetal and neonatal development and maturation before and after birth.

The role of placental malperfusion in the pathogenesis of preeclampsia in dichorionic twin and singleton pregnancies

INTRODUCTION

In singletons, the pathogenesis of hypertensive disorders of pregnancy (HDP) is attributed to abnormal placentation, characterized by maternal vascular malperfusion (MVM) lesions. Whether MVM plays a similar role in twin pregnancies is unclear. The purpose of the study was to compared placental pathology findings between dichorionic-twin and singleton pregnancies complicated by HDP.

METHODS

Retrospective cohort study of women with dichorionic-twin or singleton pregnancies complicated by HDP who gave birth in a single tertiary center between 2001 and 2015. Placental abnormalities were classified into lesions associated with MVM, fetal vascular malperfusion, placental hemorrhage and chronic villitis. Placental findings and neonatal outcomes were compared between twin and singleton pregnancies.

RESULTS

A total of 144 women with twins and 768 women with a singleton pregnancy met the inclusion criteria. Compared with HDP singletons, twins with HDP had higher mean birth weights, were less likely to be small for gestational age and be born at <34 and at <32 weeks. Twins had lower odds for placental weight below <10th percentile (aOR 0.49, 95%CI 0.33-0.71), for MVM pathology (aOR 0.28, 95%CI 0.20-0.39) and for fetal vascular malperfusion pathology (aOR 0.65, 95%CI 0.45-0.93). These finding remained significant in the subpopulation of early onset HDP (<34 weeks) and small for gestational newborn.

DISCUSSION

Our findings support the hypothesis that MVM are less relevant to the pathogenesis of HDP in twin pregnancies and suggest that other placental or non-placental factors are responsible for the increased risk of HDP in twin pregnancies.

Preeclampsia: Pathogenesis, Prevention, and Long-Term Complications

Preeclampsia continues to afflict 5% to 8% of all pregnancies throughout the world and is associated with significant morbidity and mortality to the mother and the fetus. Although the pathogenesis of the disorder has not yet been fully elucidated, current evidence suggests that imbalance in angiogenic factors is responsible for the clinical manifestations of the disorder, and may explain why certain populations are risk. In this review, we begin by demonstrating the roles that angiogenic factors play in pathogenesis of preeclampsia and its complications in the mother and the fetus. We then continue to report on the use of angiogenic markers as biomarkers to predict and risk-stratify disease. Strategies to treat preeclampsia by correcting the angiogenic balance, either by promoting proangiogenic factors or by removing antiangiogenic factors in both animal and human studies, are discussed. We end the review by summarizing status of the current preventive strategies and the long-term cardiovascular outcomes of women afflicted with preeclampsia.

Complications in multiple gestation pregnancy: A cross-sectional study of ten maternal-fetal medicine centers in China

Complications in women with multiple gestation pregnancy have not been studied in China. We aimed to establish a database of women with multiple gestation pregnancy and investigate the complications related to multiple pregnancy. We conducted a cross-sectional study that included 3246 women with multiple gestation pregnancy and who had multiple live-birth deliveries; the women were registered at ten maternal-fetal medicine centers in China in 2013. All participants completed a detailed questionnaire that included basic demographic information, history of gestation and abnormal fetal development, risk factors during pregnancy, and pregnancy outcomes. Overall, 1553 (47.8%) women experienced pregnancy complications; these women were more likely to have lower height and less education than women who did not experience complications. However, women who experienced complications had a higher twin birth rate and were more likely to have received regular antenatal care and assisted reproductive technology than women without complications (P < 0.05). Notably, preterm birth was a primary complication in multiple pregnancy (n = 960). In conclusion, pregnancy complications, especially preterm birth, were relatively common in women with multiple gestation pregnancy. The findings from this cross-sectional study in China may be used as a foundation for investigating risk factors for complications in women with multiple gestation pregnancy in the future.

Accuracy of Home-Based Ultrasonographic Diagnosis of Obstetric Risk Factors by Primary-Level Health Care Workers in Rural Nepal

OBJECTIVE

To assess the feasibility of ultrasonographic task shifting by estimating the accuracy at which primary-level health care workers can perform community-based third-trimester ultrasound diagnosis for selected obstetric risk factors in rural Nepal.

METHODS

Three auxiliary nurse-midwives received two 1-week ultrasound trainings at Tribhuvan University Teaching Hospital in Kathmandu. At a study site in rural Nepal, pregnant women who were 32 weeks of gestation or greater were enrolled and received ultrasound examinations from the auxiliary nurse-midwives during home visits. Each auxiliary nurse-midwife screened for noncephalic presentation, multiple gestation, and placenta previa. Deidentified digital ultrasonograms were stored and uploaded onto an online server, where certified sonologists and ultrasonographers reviewed the images and made their own diagnoses for the three conditions. Accuracy of auxiliary nurse-midwife diagnoses was then calculated.

RESULTS

A total of 804 women contributed to the analysis. Each auxiliary nurse-midwife's κ statistic for diagnosis of noncephalic presentation was above 0.90 compared with the ultrasonogram reviewers. Sensitivity, specificity, and positive and negative predictive values were between 90% and 100% for all auxiliary nurse-midwives. For multiple gestation, the auxiliary nurse-midwives were in perfect agreement with both the ultrasonogram reviewers and maternal postpartum self-report. Two placenta previa cases were detected, and the ultrasonogram reviewers agreed with both.

CONCLUSION

With limited training, primary-level health care workers in rural Nepal can accurately diagnose selected third-trimester obstetric risk factors using ultrasonography.

Second-trimester urine nephrin:creatinine ratio versus soluble fms-like tyrosine kinase-1:placental growth factor ratio for prediction of preeclampsia among asymptomatic women

This prospective observational study compare urine nephrin:creatinine ratio (NCR, ng/mg) with serum soluble fms-like tyrosine kinase-1:placental growth factor ratio (FPR, pg/pg) for preeclampsia (PE) prediction among unselected asymptomatic pregnant women in 2^nd trimester. NCR and FPR were determined in 254 paired urine/blood samples collected simultaneously from 254 women at median gestational week (GW) 24 (range, 22–27) without hypertension or significant proteinuria in pregnancy (SPIP). Fifteen (5.9%) developed SPIP and hypertension at GW 34.0 (26.0–38.6) and 35.3 (27.6–38.6), respectively, and were diagnosed with PE at GW 35.7 (27.6–38.6). The 90^th percentile level determined in 239 women normotensive throughout pregnancy gave NCR (139) sensitivity and positive predictive values (PPV) of 60% (9/15) and 27% (9/33), while those for serum FPR (4.85) were 40% (6/15) and 20% (6/30), respectively. Relative risks (95%CI) of later PE were 10.0 (3.82–26.4; 27% [9/33] vs. 2.7% [6/221]) and 4.98 (1.91–13.0; 20% [6/30] vs. 4.0% [9/224]) for NCR-positive and FPR-positive women, respectively. Cut-offs suggested by ROC gave NCR (86.6) sensitivity and PPV of 87% (13/15) and 17% (13/79), and FPR (8.8) values of 40% (6/15) and 40% (6/15), respectively. Thus, 2^nd trimester NCR was superior to FPR for PE prediction.

Clinical characteristics of fetal and neonatal outcomes in twin pregnancy with preeclampsia in a retrospective case-control study: A STROBE-compliant article

The aim of our study was to compare the clinical characteristics of fetal and neonatal outcomes in twin pregnancies between women with preeclampsia (PE) and those with normotension in a Chinese population.There were 143 preeclamptic women and 367 normotensive women with twin pregnancies included in this retrospective case-control study. The baseline characteristics and perinatal outcomes were collected and compared between the groups. Multiple logistic regression and linear regression were used to assess the correlations between PE and the outcomes.Significant increases were observed in the frequencies of preterm delivery (OR = 2.75, P < 0.001), iatrogenic preterm birth (OR = 3.52, P < 0.001), and IUGR (OR = 2.94, P = 0.001) in the PE group, and the PE group had more than a 2-fold risk of adverse neonatal outcomes. Preeclamptic twin neonates had lower birth weights (β = -147.34, P = 0.005; β = -169.47, P = 0.001). The comparison on the discordance of intertwin weight was not significantly different.Twin pregnancies with PE are associated with worse perinatal outcomes. The adverse outcomes of preeclamptic twin pregnancies may be associated with lower birth weights rather than the discordance of the intertwin weight, which requires further confirmation. The results may provide helpful references for better clinical assessments, evaluations of prognosis, and a deeper understanding of preeclamptic twin pregnancies.

Evidence for No Significant Impact of Müllerian Anomalies on Reproductive Outcomes of Twin Pregnancy in Korean Women

The present article aimed to evaluate the impact of congenital Müllerian anomalies (MA) on twin pregnancy after 24 gestational weeks in Korean women. All records of twin pregnancies in a large maternity hospital in Korea between January 2005 and July 2013 were analyzed. Patients with monochorionic monoamniotic (MCMA) twins, non-Korean patients, patients with twins delivered prior to 24 gestational weeks, and patients with miscarriage of one fetus or intrauterine fetal death (IUFD) before 24 gestational weeks were excluded from data analysis. In total, 1,422 women with twin pregnancy were eligible for data analysis, including 17 (1.2%) who had a known congenital MA (septate uterus, bicornuate uterus, arcuate uterus, and unicornuate uterus). Except for the mode of conception, baseline demographics were similar between women with MA and those without MA. No significant differences were found in pregnancy outcomes of gestational age at delivery (p = .86), birth weight of smaller and larger twins (p = .54 and p = .65), and number of twins with birth weight <5th percentile for gestational age (p = .43).The rates of obstetrical complications such as pre-eclampsia, gestational diabetes mellitus (GDM), placenta previa, cerclage, IUFD, and postpartum hemorrhage were not significantly different between the two groups either. We concluded that the presence of congenital MA may not increase obstetrical risks in outcomes of pregnancy of twins delivered after 24 gestational weeks.

Clinical features and prenatal risk factors for hypertensive disorders in twin pregnancies

AIM

The aim of this study was to identify the incidence, clinical features, and prenatal risk factors for hypertensive disorders, including gestational hypertension (GH) and pre-eclampsia (PE), in twin pregnancies.

MATERIAL AND METHODS

We carried out a retrospective cohort study of twin pregnancies managed from the first trimester onward at a single center from 2002 through 2011. We retrospectively evaluated the incidence, severity, time-point onset of GH or PE, as well as maternal and neonatal outcomes. Prenatal risk factors for disease were also analyzed with a multivariable logistic regression model.

RESULTS

Of 742 twin pregnancies, 165 (22%) were diagnosed with GH or PE. Five women developed GH or PE at <32 weeks' gestation (early onset), and the remaining 160 developed them at ≥ 32 weeks (late onset). Of all 165 cases, 110 women (66.7%) developed their disease during the intrapartum or postpartum period. The significant risk factors associated with developing a hypertensive disorder in a twin pregnancy were primiparity (adjusted odds ratio [aOR]: 1.77; 95% confidence interval [CI]: 1.21-2.61), pregestational high body mass index (aOR 1.35, 95%CI: 1.08-1.70), family history of hypertension (aOR: 1.50; 95%CI: 1.02-2.17) and previous history of GH or PE (aOR 8.85; 95%CI: 2.70-29.0).

CONCLUSIONS

One-fifth of the twin pregnancies developed GH or PE. Furthermore, more than half of the patients were diagnosed with the disease during the intrapartum or postpartum period. Significant risk factors for GH or PE in twin pregnancies were primiparity, pregestational body mass index, family history of hypertension, and history of a hypertensive disorder during a previous pregnancy. The significance of monitoring blood pressure after delivery for a twin pregnancy is stressed.

eNOS haplotypes associated with gestational hypertension or preeclampsia

AIMS

Polymorphisms in the endothelial nitric oxide synthase (eNOS) gene have been inconsistently associated with preeclampsia. We compared genotype and haplotype frequencies of three eNOS gene polymorphisms in normotensive and hypertensive pregnancies.

METHODS

Genotypes and haplotypes for eNOS polymorphisms (T-786C, Glu298Asp and intron 4 b/a) were determined in 326 pregnant women (110 healthy pregnancies, 103 gestational hypertensives and 113 preeclamptic).

RESULTS

No differences were observed in the frequencies of genotypes and alleles of the three polymorphisms among the groups (all p > 0.05). However, the haplotype 'T Glu a' was more common in healthy pregnancies than in gestational hypertensives or preeclamptic (20 vs 6 and 6%, respectively; p < 0.0032). Conversely, the haplotype 'C Glu a' was more common in gestational hypertensives and preeclamptic than in healthy pregnancies (17 vs 17 and 5%; p = 0.0061).

CONCLUSION

These findings suggest a contribution of eNOS haplotypes to the development of hypertensive disorders of pregnancy that is obscured when specific eNOS genotypes alone are considered.

Twin pregnancies: eating for three? Maternal nutrition update

The incidence of multifetal pregnancies has increased, mainly because of assisted reproduction treatments. This trend is reflected in increased maternal and neonatal morbidity and mortality. While the optimum maternal nutrition and weight gain patterns for singleton pregnancies is well documented, there is a paucity of information for twin pregnancies. Although it is assumed that optimum nutritional requirements and weight gains would be greater for twin than for singleton gestations, research is needed to establish the optima. This article is a collation of available recommendations for maternal nutrition and weight gain patterns in twin pregnancies.