Obstetric outcomes for twins from different conception methods - A multicenter cross-sectional study from China

How does the need for IVF affect pregnancy complications among multiple gestations? The study of a large American population database including almost 100,000 multiple gestations

Objective

This study's aim is to compare pregnancy outcomes in multifetal gestations that were conceived spontaneously compared to in vitro fertilization (IVF). Few population-based studies have addressed this topic.

Study design

This is a retrospective cohort study using the Health Care Cost and Utilization Project-Nationwide Inpatient Sample (HCUP-NIS) database. Our study cohort included 90,552 multifetal gestations conceived spontaneously and 3219 IVF conceptions, from 2008 to 2014, inclusively. Multivariate logistic regression analyses were performed comparing maternal and neonatal outcomes, whilst adjusting for confounding variables. Subject was conducted using ICD-9 codes for multifetal gestation: 651. X and 76.1 and ICD-9 code for IVF: 23.85. Each pregnancy was included once.

Results and conclusion

IVF multifetal gestations had increased risk of pregnancy-induced hypertension (aOR 1.31, 95 % CI 1.20-1.43), gestational hypertension (aOR 1.21, 95 % CI 1.04-1.41), preeclampsia (aOR 1.31, 95 % CI 1.19-1.45), gestational diabetes (aOR 1.26, 95 % CI 1.13-1.41) and placenta previa (aOR 1.7, 95 % CI 1.32-2.19). IVF delivery outcomes were more likely complicated by cesarean section (aOR 1.21, 95 % CI 1.10-1.33), preterm premature rupture of membranes (aOR 1.33, 95 % CI 1.16-1.52), chorioamnionitis (aOR 1.71, 95 % CI 1.37-2.14), postpartum hemorrhage (aOR 1.44, 95 % CI 1.26-1.63) and transfusions (aOR 1.48, 95 %CI 1.26-1.74). IVF neonatal outcomes were more likely complicated by small for gestational age (aOR 1.26, 95 % CI 1.12-1.41) and congenital anomalies (aOR 1.82, 95 % CI 1.29-2.57). IVF was not found to increase risks of eclampsia, preterm delivery, operative vaginal delivery, hysterectomy, or intrauterine fetal demise.IVF increased the risk of pregnancy, delivery, and neonatal outcomes in multifetal pregnancies with risks increased from 20 % to 70 %. The role of infertility versus the need for IVF and the type of IVF protocol used should be further evaluated.

Risk factors for postpartum hemorrhage in twin pregnancies with cesarean section

The rates of twin pregnancies and cesarean section have increased in recent years, and both of them are at high risks of postpartum hemorrhage (PPH). However, few studies have concentrated on the risks of PPH in twin pregnancies and cesarean deliveries. In this study, we aimed to identify the risk factors for PPH among twin-pregnant women with cesarean section. This was a retrospective observational study including 1,649 women with twin pregnancies delivered by cesarean section from 2016 to 2022 in the Second Affiliated Hospital of Wenzhou Medical University, China. The eligible women were divided into PPH group (n = 116) and non-PPH group (n = 1,533) according to the blood loss after delivery within 24 h. The baseline maternal and perinatal characteristics were compared between the two groups. Logistic regression analysis was conducted to identify the potential risk factors for PPH. We found nulliparity, assisted reproductive technology (ART) usage, preeclampsia or HELLP syndrome, placenta previa, placenta accreta and general anesthesia were more common in PPH group than non-PPH group (P < 0.05). Women in PPH group had higher maternal body mass index at delivery and higher combined birthweight of the twins than non-PPH group, but had lower parity (P < 0.05). Seven independent risk factors for PPH were identified after logistic regression analysis: ART usage (OR 2.354 95% CI 1.357-4.083, P = 0.002), preeclampsia or HELLP syndrome (OR 2.605, 95% CI 1.471-4.616, P = 0.001), placenta previa (OR 7.325, 95% CI 3.651-14.697, P < 0.001), placenta accreta (OR 6.296, 95% CI 1.316-30.12, P = 0.021), thrombocytopenia (OR 1.636, 95% CI 1.056-2.535, P = 0.027), general anesthesia (OR 2.394, 95% CI 1.223-4.686, P = 0.011), and combined birthweight (OR 1.00032, 95% CI 1.00005-1.00059, P = 0.020). Collectively, in women with twin pregnancies delivered by cesarean section, the use of ART, preeclampsia or HELLP syndrome, placenta previa, placenta accreta, thrombocytopenia, general anesthesia and the combined birthweight were identified as independent risk factors for PPH. More attention should be paid to women with these risk factors.

Systematic review and meta-analysis on placenta accreta spectrum disorders in twin pregnancies: risk factors, detection rate and histopathology

INTRODUCTION

The occurrence of PAS has been recently associated with the presence of twin pregnancy. Aim of this review is to report the risk factors, histopathological correlation, diagnostic accuracy of prenatal ultrasound and clinical outcome of twin pregnancies complicated by placenta accreta spectrum (PAS) disorders.

EVIDENCE ACQUISITION

PubMed, Embase, Cinahl, Clinical Trial.Gov and Google Scholar databases were searched. Inclusion criteria were studies on twin pregnancies complicated by PAS. The outcomes explored were risk factors for PAS (including placenta previa, prior uterine surgery or assisted reproductive technology, ART), histopathology (placenta accreta and increta/percreta), detection rate of prenatal ultrasound and clinical outcome, including need for blood transfusion, hysterectomy, emergency or scheduled Cesarean delivery (CD), and maternal death. Random effect meta-analyses of proportions were sued to combine the data.

EVIDENCE SYNTHESIS

Two studies considering 103 pregnancies were included in this systematic review: 41.86% (95% CI 27.0-57.9) of twin pregnancies complicated by PAS disorders had a prior CD, 28.22% (95% CI 13.4-46.0) presented placenta previa and 58.14% (95% CI 42.1-73.0) of twin pregnancies were conceived by ART. 74.49% (95% CI 41.6-96.5) of PAS in twin pregnancies were placenta accreta, while 25.51% (95% CI 3.5-58.4) were placenta increta or percreta. Prenatal diagnosis of PAS in twin pregnancies was accomplished only in 27.91% (95% CI 15.3-43.7) of cases. Finally, only one study consistently reported the clinical outcome of PAS in twins. 31.67% (95% CI 20.3-45.0) of women required blood transfusion, 26.67% (95% CI 16.1-39.7) had hysterectomy, while there was no case of maternal death. 44.19% of women had an emergency CD.

CONCLUSIONS

There is still limited evidence on the clinical course of PAS disorders in twin pregnancies. Placenta previa, prior uterine surgery (mainly CD), and ART are the most commonly risk factors for PAS disorders in twins. Prenatal diagnosis of PAS in twins is lower compared to what reported in singleton. Finally, about 30% of women with a twin pregnancy complicated by PAS required blood transfusion and hysterectomy.

Serum lipid profile in relation to free thyroxine and the effect of levothyroxine treatment on lipids in patients with isolated hypothyroxinemia during pregnancy: a single-center retrospective study

BACKGROUND

Thyroid function is widely considered a lipid metabolism regulator. However, studies on lipid metabolism in pregnant women with low free thyroxine (FT₄) levels are limited and inconclusive. Furthermore, the association between maternal FT₄ deficiency and adverse lipid metabolic parameters is unknown. Therefore, we aimed to investigate this association and the effects of levothyroxine (L-T₄) treatment on these metabolic indicators.

METHODS

This retrospective study included 164 patients with isolated hypothyroidism (IH) (FT₄ levels below the 5^th percentile with normal thyroid stimulating hormone levels according to the gestational-specific reference range) and 407 euthyroidism patients (control group who had regular antenatal examinations at Zhejiang Provincial People's Hospital, Hangzhou, China) between January 1, 2019, and December 31, 2020. Patients with IH were divided into levothyroxine (L-treatment group, n = 77) and dietary iodine supplement treatment groups (dietary treatment group, n=87) according to the hospital's treatment policy and clinical experience. The intervention lasted for at least 8 weeks. Metabolic indicators, including thyroid function and lipid parameters, were collected at least twice before and after the intervention. Other data collected included maternal age, history of abortion, prepregnancy BMI, and gestational weight gain (Fig. 1).

RESULTS

Compared with the control group, Patients with IH had a higher degree of dyslipidemia, reflected in elevated total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and apolipoprotein B (Apo B) levels. In IH patients, an inverse correlation was found between FT₄ and TG levels, which remained after adjusting for prepregnancy BMI. The L-treatment group demonstrated a significantly slower rate of hypercholesterolemia progression during pregnancy than the dietary treatment group. In addition, there was a relationship between the therapeutic effect and the degree of disease, with the main factors being FT₄, TSH and TG levels prior to starting treatment.

CONCLUSIONS

Low FT₄ levels were associated with elevated blood lipid levels. Serum FT₄ and lipid levels in patients could be improved by medical intervention.

Adverse outcomes associated with twin pregnancies conceived via in vitro fertilization

OBJECTIVE

To compare adverse pregnancy and neonatal outcomes in twin pregnancies conceived by in vitro fertilization (IVF) to those conceived spontaneously.

METHODS

Retrospective analysis of the Centers for Disease Control and Prevention, Natality Live Birth database for the years 2016-2019. All twin live births were included and stratified into two groups: those from pregnancies conceived via IVF and those from pregnancies conceived spontaneously. The incidence of several adverse pregnancy and neonatal outcomes were compared between the two groups. Statistical analysis included multivariable logistic regression to adjust for the following potential confounders: maternal age, race/ethnicity, body mass index, education level, type of medical insurance, chronic hypertension, pregestational diabetes, and prior preterm birth. Data were presented as adjusted odds ratios (aOR) with 95% confidence intervals (CI).

RESULTS

Twin live births from pregnancies conceived via IVF comprised 9.5% of the study cohort (39,356 of 415,560). Baseline characteristics varied significantly between IVF and spontaneously conceived twins. After adjusting for these variables, IVF in twins was associated with an increased risk of multiple adverse outcomes including gestational diabetes (aOR = 1.35, 95% CI = 1.30-1.39), hypertensive disorders of pregnancy (aOR = 1.70, 95% CI = 1.65-1.75), preterm birth prior to 28 weeks (aOR = 1.53, 95% CI = 1.43-1.63), maternal intensive care unit admission (aOR = 2.03, 95% CI = 1.79-2.31), maternal blood transfusion (aOR = 2.97, 95% CI = 2.75-3.20), unplanned hysterectomy (aOR = 3.37, 95% CI = 2.73-4.16), and prolonged ventilation in newborns (aOR = 1.76, 95% CI = 1.69-1.82), compared to spontaneously conceived twin pregnancies.

CONCLUSIONS

Based on this large United States population-based cohort, twin pregnancies conceived via IVF represent a subgroup of twins that have an increased risk for several adverse pregnancy and neonatal outcomes, compared to those conceived spontaneously. With increased contemporary utilization of IVF, obstetricians should consider these risks while caring for patients with twin pregnancies conceived via IVF.

The changing impact of assisted reproductive techniques on preterm birth during the period 2007-2020 in Lombardy, Northern Italy

OBJECTIVE

To assess the impact of Assisted Reproductive Techniques (ART) on the risk of preterm birth (PTB).

STUDY DESIGN

This retrospective population-based study used healthcare utilization databases of the Lombardy Region to select all the deliveries occurred between 2007 and 2020. Log-binomial regression models were fitted to estimate prevalence ratio (PR) and the corresponding 95% confidence interval (CI) of PTB among deliveries after ART. Estimates were adjusted for maternal sociodemographic features. Furthermore, the population attributable fraction was computed. All the analyses were performed for calendar period and were repeated excluding multiple births.

RESULTS

In our cohort, an increasing trend in the number of ART emerged, with an overall rate of 25.8 per 1,000 deliveries (N = 28,742). ART was positively related to PTB (aPR = 2.83, 95 % CI: 2.76-2.91) with a downward trend. Over the period study, multiple births after ART decreased (from 20.4 % to 8.4 %) and were constantly burdened by a higher number of PTB. Excluding multiple births, the association was substantially lower (aPR = 1.72, 95 % CI: 1.65-1.79) and did not describe any trend. Moreover, stratifying for type of pregnancy, the association was observed only among singletons. Finally, the proportion of PTB considered attributable to ART increased from about 2-3 % to 6 % till the 2016, then decreased.

CONCLUSION

The investigation suggested that ART was related to PTB; this association may be partly justified by the high rate of multiple births among women who conceived non spontaneously. However, excluding multiple births, ART remained associated with PTB.

The Maternal-Neonatal Outcomes of Twin Pregnancies with Preeclampsia and Their Association with Assisted Reproductive Technology: A Retrospective Study

Objective: This study aimed to investigate the maternal−neonatal outcomes of twin pregnancies of mothers with preeclampsia and their association with assisted reproductive technology (ART). Methods: A retrospective study on the clinical and maternal−neonatal outcome data of 698 women with twin pregnancies who delivered in our hospital from December 2013 to September 2021 was conducted. Continuous variables were analyzed using a Student’s t-test or Wilcoxon rank-sum test. Categorical variables were analyzed using the Chi-square test. The risk factors of twin pregnancies with preeclampsia were analyzed by logistic regression. Results: The rate of twin pregnancy complicated by preeclampsia was 17.62% (123/698). Logistic regression analysis showed that ART increased the risk of preeclampsia in twin pregnancies (AOR: 1.868, 95% CI: 1.187−2.941). Mothers with preeclampsia carrying twins conceived with ART had a higher rate of delivery at gestational week < 34 (29.9% vs. 12.5%) and asphyxia of the neonate at 5 min after delivery (13.4% vs. 1.8%) than those with preeclampsia conceived without ART (p < 0.05). Conclusions: ART increases the risk of preeclampsia in twin pregnancies and the rate of adverse maternal−neonatal outcomes for twin pregnancies with preeclampsia. The policy of single embryo transfer is a method to reduce the adverse pregnancy outcomes of ART.

Twin Growth Discordance and Risk of Postpartum Hemorrhage: A Retrospective Cohort Study

Background

In recent years, the incidence of postpartum hemorrhage has increased globally. Multiple pregnancies and cesarean sections are well-known risk factors for postpartum hemorrhage. No studies have evaluated the associations between fetal growth anomalies and postpartum hemorrhage in women with twin pregnancies undergoing cesarean section. This study aimed to identify the relationship between fetal growth anomalies and postpartum hemorrhage in women with twin pregnancies undergoing cesarean section.

Methods

This retrospective single-center study included 3,180 women with twin pregnancies at a tertiary hospital between August 2013 and July 2020. Singleton reference charts were used to assess fetal growth restriction at birth. Discordant growth was defined as an intertwin birth weight difference of ≥20%. Logistic regression analyses were used to evaluate the association between fetal growth anomalies and postpartum hemorrhage. Additionally, sensitivity analysis of abnormal placenta and stratification by twin chorionicity were conducted.

Results

The overall incidence of postpartum hemorrhage was 4.3%. Twin growth discordance, especially with fetal growth restriction, was associated with an increased risk of postpartum hemorrhage (adjusted odds ratio [AOR] = 1.62, 95% confidence interval [CI], 1.05-2.51, P = 0.031; AOR = 1.71; 95% CI, 1.08-2.70, P = 0.022; AOR = 1.98, 95% CI, 1.21-3.25, P = 0.006, respectively). After stratification, this relationship persisted in dichorionic twins (OR = 1.71, 95% CI, 1.04-2.82, P = 0.036; OR = 1.90, 95% CI, 1.13-3.21, P = 0.016; OR = 2.48, 95% CI, 1.41-4.38, P = 0.002, respectively). However, no significant association was observed in monochorionic twin pregnancies.

Conclusion

Growth discordance, especially complicated by fetal growth restriction, was associated with an increased risk of postpartum hemorrhage in women with twin pregnancies undergoing cesarean section, and was more evident in patients with dichorionic twins.

Additional Adverse Perinatal Outcomes With No Effect on Neonatal Mortality and Birth Defects in Pregnancies Conceived by Assisted Reproductive Technology

BACKGROUND

Pregnancy outcomes and perinatal diseases of children conceived by assisted reproductive technology (ART) and spontaneous conception (SC) are still unclear. We sought to compare the effects of ART and SC on adverse neonatal outcomes.

METHODS

We included 5,913 neonates admitted to the neonatal intensive care unit (NICU) of the First Affiliated Hospital of the University of Science and Technology of China between January 2017 and December 2020. There were 1,112 (18.8%) ART pregnancies and 4,801 (81.2%) SC pregnancies. Data on maternal characteristics, comorbidities during pregnancy, and neonatal outcomes were collected and analyzed. Logistic regression models estimated the odds ratios (ORs) and 99% CIs of neonatal outcomes according to ART pregnancy. Neonatal outcomes primarily included neonatal respiratory distress syndrome (NRDS), bronchopulmonary dysplasia (BPD), retinopathy of prematurity (ROP), neonatal anemia, birth defects, and mortality.

RESULTS

Among 5,913 neonates, 485 (8.2%) had NRDS, 165 (2.8%) had BPD, 113 (1.9%) had ROP, 602 (10.2%) had neonatal anemia, and 1,112 (18.8%) were ART infants. The incidence of pregnancy-related complications, such as gestational diabetes mellitus (GDM), gestational hypothyroidism, and rheumatic immune diseases, in mothers receiving ART, was higher than that in the SC group. On multivariate analysis, ART was independently associated with NRDS (OR = 1.46; 95% CI, 1.11-1.93; p = 0.008) and ROP (OR = 1.79; 95% CI, 1.06-3.05; p = 0.031). Moreover, the association persisted after adjustment for maternal age, history of cesarean section, preconception factors, and pregnancy complications. For BPD (OR = 1.44; 95% CI, 0.91-2.27; p = 0.117) and neonatal anemia (OR = 1.12; 95% CI, 0.87-1.45; p = 0.373), the associations were attenuated substantially when adjusting for pregnancy complications. ART was associated with neither birth defects (OR = 0.98; 95% CI, 0.77-1.25; p = 0.889) nor mortality (OR = 0.98; 95% CI, 0.51-1.91; p = 0.961).

CONCLUSION

ART was independently associated with adverse neonatal outcomes, including NRDS and ROP. Therefore, women who conceive by ART must improve their perinatal health and management of pregnancy-related comorbidities to enhance the quality of life of their offspring.