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American Journal of Obstetrics &... Mar 2022Monoamniotic twin pregnancies are rare, but early diagnosis of such pregnancies is critical, as the incidence of complications in these pregnancies is much higher than... (Review)
Review
Monoamniotic twin pregnancies are rare, but early diagnosis of such pregnancies is critical, as the incidence of complications in these pregnancies is much higher than in diamniotic or dichorionic twin pregnancies. Overall, only 70% of all monoamniotic twins will survive. Furthermore, approximately half of fetal deaths in these pregnancies are because of the high incidence of fetal anomalies (15%-25%), such as twin reversed arterial perfusion sequence and conjoined twinning. Therefore, early anatomy screening in the first trimester of pregnancy is recommended. Other causes of fetal death in these pregnancies include twin-twin transfusion syndrome, tight cord entanglement, or acute hemodynamic imbalances through the large placental vascular anastomoses. After viability, fetal surveillance can be intensified, as this decreases the risk of in utero death. Both inpatient and outpatient surveillance are reasonable. If otherwise uncomplicated, monoamniotic twins should be delivered at 33 to 34 weeks' gestation. Most centers will deliver by cesarean delivery, but some continue to advocate for vaginal delivery. Lastly, neonatal morbidity is high in monoamniotic twin pregnancies and is mainly related to prematurity.
Topics: Female; Fetal Death; Gestational Age; Humans; Infant, Newborn; Placenta; Pregnancy; Pregnancy, Twin; Ultrasonography, Prenatal
PubMed: 34728404
DOI: 10.1016/j.ajogmf.2021.100520 -
Ultrasound in Obstetrics & Gynecology :... Jun 2021Despite many advances in antenatal care, twin pregnancies still experience more adverse outcomes, in particular perinatal morbidity and mortality. They also pose a... (Review)
Review
Despite many advances in antenatal care, twin pregnancies still experience more adverse outcomes, in particular perinatal morbidity and mortality. They also pose a multitude of challenges and controversies, as outlined in this Review. Moreover, they are less likely to be included in clinical trials. Many issues on classification and management remain under debate. Efforts at standardizing diagnostic criteria, monitoring protocols, management and outcome reporting are likely to reduce their perinatal risks. The top 10 most important research uncertainties related to multiple pregnancies have been identified by both clinicians and patients. More robust research in the form of randomized trials and large well-conducted prospective cohort studies is needed to address these controversies. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
Topics: Female; Humans; Pregnancy; Pregnancy, Twin; Prenatal Care
PubMed: 32799348
DOI: 10.1002/uog.22181 -
Obstetrics and Gynecology Sep 2019To investigate the relationship between endometriosis and adverse pregnancy outcomes. (Observational Study)
Observational Study
OBJECTIVE
To investigate the relationship between endometriosis and adverse pregnancy outcomes.
METHODS
Women between ages 25 and 42 years in 1989 (n=116,429) reported detailed information on pregnancies and reproductive health at baseline and every 2 years thereafter in the Nurses' Health Study II, a cohort study. In 2009, they completed a detailed, pregnancy-focused questionnaire. A total of 196,722 pregnancies were reported. Adverse pregnancy outcomes included spontaneous abortion, ectopic pregnancy, stillbirth, gestational diabetes mellitus (GDM), hypertensive disorders of pregnancy (preeclampsia or gestational hypertension), preterm birth, and low birth weight. We estimated the relative risks (RRs) and 95% CIs of adverse pregnancy outcomes comparing pregnancies in women with and without a history of laparoscopically confirmed endometriosis using multivariable log-binomial regression, with generalized estimating equations to account for multiple pregnancies per woman.
RESULTS
Endometriosis was associated with a greater risk of pregnancy loss (spontaneous abortion: RR 1.40, 95% CI 1.31-1.49; ectopic pregnancy: RR 1.46, 95% CI 1.19-1.80). Endometriosis was also associated with a greater risk of GDM (RR 1.35, 95% CI 1.11-1.63) and hypertensive disorders of pregnancy (RR 1.30, 95% CI 1.16-1.45).
CONCLUSIONS
We observed an association between laparoscopically confirmed endometriosis and several adverse pregnancy outcomes. Future research should focus on the potential biological pathways underlying these relationships to inform screening or preventive interventions.
Topics: Abortion, Spontaneous; Adult; Cohort Studies; Endometriosis; Female; Humans; Pregnancy; Pregnancy Complications; Pregnancy Outcome; Risk
PubMed: 31403584
DOI: 10.1097/AOG.0000000000003410 -
Prenatal Diagnosis Sep 2021Twin pregnancies are common and associated with pregnancy complications and adverse outcomes. Prenatal clinical management is intensive and has been hampered by inferior... (Review)
Review
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.
Topics: Adult; Aneuploidy; Female; Humans; Noninvasive Prenatal Testing; Pregnancy; Pregnancy Maintenance; Pregnancy, Twin
PubMed: 34170028
DOI: 10.1002/pd.5989 -
Human Reproduction Update Nov 2023Estrogens regulate disparate female physiological processes, thus ensuring reproduction. Altered estrogen levels and signaling have been associated with increased risks... (Review)
Review
The pathophysiological role of estrogens in the initial stages of pregnancy: molecular mechanisms and clinical implications for pregnancy outcome from the periconceptional period to end of the first trimester.
BACKGROUND
Estrogens regulate disparate female physiological processes, thus ensuring reproduction. Altered estrogen levels and signaling have been associated with increased risks of pregnancy failure and complications, including hypertensive disorders and low birthweight babies. However, the role of estrogens in the periconceptional period and early pregnancy is still understudied.
OBJECTIVE AND RATIONALE
This review aims to summarize the current evidence on the role of maternal estrogens during the periconceptional period and the first trimester of pregnancies conceived naturally and following ART. Detailed molecular mechanisms and related clinical impacts are extensively described.
SEARCH METHODS
Data for this narrative review were independently identified by seven researchers on Pubmed and Embase databases. The following keywords were selected: 'estrogens' OR 'estrogen level(s)' OR 'serum estradiol' OR 'estradiol/estrogen concentration', AND 'early pregnancy' OR 'first trimester of pregnancy' OR 'preconceptional period' OR 'ART' OR 'In Vitro Fertilization (IVF)' OR 'Embryo Transfer' OR 'Frozen Embryo Transfer' OR 'oocyte donation' OR 'egg donation' OR 'miscarriage' OR 'pregnancy outcome' OR 'endometrium'.
OUTCOMES
During the periconceptional period (defined here as the critical time window starting 1 month before conception), estrogens play a crucial role in endometrial receptivity, through the activation of paracrine/autocrine signaling. A derailed estrogenic milieu within this period seems to be detrimental both in natural and ART-conceived pregnancies. Low estrogen levels are associated with non-conception cycles in natural pregnancies. On the other hand, excessive supraphysiologic estrogen concentrations at time of the LH peak correlate with lower live birth rates and higher risks of pregnancy complications. In early pregnancy, estrogen plays a massive role in placentation mainly by modulating angiogenic factor expression-and in the development of an immune-tolerant uterine micro-environment by remodeling the function of uterine natural killer and T-helper cells. Lower estrogen levels are thought to trigger abnormal placentation in naturally conceived pregnancies, whereas an estrogen excess seems to worsen pregnancy development and outcomes.
WIDER IMPLICATIONS
Most current evidence available endorses a relation between periconceptional and first trimester estrogen levels and pregnancy outcomes, further depicting an optimal concentration range to optimize pregnancy success. However, how estrogens co-operate with other factors in order to maintain a fine balance between local tolerance towards the developing fetus and immune responses to pathogens remains elusive. Further studies are highly warranted, also aiming to identify the determinants of estrogen response and biomarkers for personalized estrogen administration regimens in ART.
Topics: Pregnancy; Female; Humans; Pregnancy Outcome; Estrogens; Pregnancy Trimester, First; Placentation; Fertilization in Vitro; Estradiol
PubMed: 37353909
DOI: 10.1093/humupd/dmad016 -
European Journal of Obstetrics,... Jun 2023To review current international clinical guidelines on the antenatal and intrapartum management of twin pregnancies, examining areas of consensus and conflict. (Review)
Review
OBJECTIVES
To review current international clinical guidelines on the antenatal and intrapartum management of twin pregnancies, examining areas of consensus and conflict.
METHODS
We conducted a database search using Medline, Pubmed, Scopus, Academic Search Complete, CINAHL and ERCI Guidelines website. Guidelines were screened for eligibility using our inclusion and exclusion criteria. Those deemed eligible were quality assessed using the AGREE II tool and relevant data was extracted.
RESULTS
We identified 21 relevant guidelines from 16 countries including two international society guidelines. There was consensus in determination of chorionicity and amnionicity within the first trimester, fetal anomaly scan between 18 and 22 weeks and the recommended screening for twin-to-twin transfusion syndrome (TTTS). For those that provided intrapartum guidance, there was agreement in recommending caesarean section to deliver monochorionic monoamniotic (MCMA) twins, epidural anaesthesia for intrapartum analgesia and the use of cardiotocography (CTG) for intrapartum fetal monitoring. The main areas of conflict included cervical length screening, frequency of ultrasound surveillance, timing of delivery of dichorionic twin pregnancies and circumstances for recommending vaginal delivery. There was a lack of advice on intrapartum management.
CONCLUSIONS
This review has highlighted the need for unified international guidance on the management of twin pregnancy. Comparisons of current guidance demonstrates a lack of confidence in the management of labour in twin pregnancies. Further evidence on intrapartum care of twin pregnancies is needed to inform practice guidelines and improve both short and long term maternal and fetal outcomes.
Topics: Pregnancy; Female; Humans; Pregnancy, Twin; Cesarean Section; Ultrasonography, Prenatal; Twins; Prenatal Care
PubMed: 37087836
DOI: 10.1016/j.ejogrb.2023.04.002 -
The Lancet. Global Health Jun 2021The COVID-19 pandemic has had a profound impact on health-care systems and potentially on pregnancy outcomes, but no systematic synthesis of evidence of this effect has... (Meta-Analysis)
Meta-Analysis
BACKGROUND
The COVID-19 pandemic has had a profound impact on health-care systems and potentially on pregnancy outcomes, but no systematic synthesis of evidence of this effect has been undertaken. We aimed to assess the collective evidence on the effects on maternal, fetal, and neonatal outcomes of the pandemic.
METHODS
We did a systematic review and meta-analysis of studies on the effects of the pandemic on maternal, fetal, and neonatal outcomes. We searched MEDLINE and Embase in accordance with PRISMA guidelines, from Jan 1, 2020, to Jan 8, 2021, for case-control studies, cohort studies, and brief reports comparing maternal and perinatal mortality, maternal morbidity, pregnancy complications, and intrapartum and neonatal outcomes before and during the pandemic. We also planned to record any additional maternal and offspring outcomes identified. Studies of solely SARS-CoV-2-infected pregnant individuals, as well as case reports, studies without comparison groups, narrative or systematic literature reviews, preprints, and studies reporting on overlapping populations were excluded. Quantitative meta-analysis was done for an outcome when more than one study presented relevant data. Random-effects estimate of the pooled odds ratio (OR) of each outcome were generated with use of the Mantel-Haenszel method. This review was registered with PROSPERO (CRD42020211753).
FINDINGS
The search identified 3592 citations, of which 40 studies were included. We identified significant increases in stillbirth (pooled OR 1·28 [95% CI 1·07-1·54]; I=63%; 12 studies, 168 295 pregnancies during and 198 993 before the pandemic) and maternal death (1·37 [1·22-1·53; I=0%, two studies [both from low-income and middle-income countries], 1 237 018 and 2 224 859 pregnancies) during versus before the pandemic. Preterm births before 37 weeks' gestation were not significantly changed overall (0·94 [0·87-1·02]; I=75%; 15 studies, 170 640 and 656 423 pregnancies) but were decreased in high-income countries (0·91 [0·84-0·99]; I=63%; 12 studies, 159 987 and 635 118 pregnancies), where spontaneous preterm birth was also decreased (0·81 [0·67-0·97]; two studies, 4204 and 6818 pregnancies). Mean Edinburgh Postnatal Depression Scale scores were higher, indicating poorer mental health, during versus before the pandemic (pooled mean difference 0·42 [95% CI 0·02-0·81; three studies, 2330 and 6517 pregnancies). Surgically managed ectopic pregnancies were increased during the pandemic (OR 5·81 [2·16-15·6]; I=26%; three studies, 37 and 272 pregnancies). No overall significant effects were identified for other outcomes included in the quantitative analysis: maternal gestational diabetes; hypertensive disorders of pregnancy; preterm birth before 34 weeks', 32 weeks', or 28 weeks' gestation; iatrogenic preterm birth; labour induction; modes of delivery (spontaneous vaginal delivery, caesarean section, or instrumental delivery); post-partum haemorrhage; neonatal death; low birthweight (<2500 g); neonatal intensive care unit admission; or Apgar score less than 7 at 5 min.
INTERPRETATION
Global maternal and fetal outcomes have worsened during the COVID-19 pandemic, with an increase in maternal deaths, stillbirth, ruptured ectopic pregnancies, and maternal depression. Some outcomes show considerable disparity between high-resource and low-resource settings. There is an urgent need to prioritise safe, accessible, and equitable maternity care within the strategic response to this pandemic and in future health crises.
FUNDING
None.
Topics: COVID-19; Female; Global Health; Humans; Infant, Newborn; Pregnancy; Pregnancy Outcome
PubMed: 33811827
DOI: 10.1016/S2214-109X(21)00079-6 -
Theoretical Medicine and Bioethics Aug 2022In this paper, I reflect on an important article by Bob Veatch in the inaugural issue of the Hastings Center Report, entitled "Experimental Pregnancy." It is a report... (Randomized Controlled Trial)
Randomized Controlled Trial
In this paper, I reflect on an important article by Bob Veatch in the inaugural issue of the Hastings Center Report, entitled "Experimental Pregnancy." It is a report and elegant analysis of the Goldzieher Study, in which nearly 400 women were randomized to receive hormonal contraception or placebo absent consent or disclosure about placebo use, resulting in several pregnancies. Noting the study's limited notoriety, I first consider the narratives that have instead dominated bioethics' approach to pregnancy and research: thalidomide and diethylstibesterol (DES). These narratives have facilitated a narrow focus on avoiding fetal risk, to the exclusion of other ethically relevant considerations. I then revisit "Experimental Pregnancy" and offer two ways in which Bob's analysis serves as an important corrective, first, by foregrounding research subjects (persons who are or may become pregnant), and second, by normalizing pregnancy and thus foregrounding foundational ethical considerations that are sometimes lost amidst pregnancy's presumed exceptionalism.
Topics: Pregnancy; Female; Humans; Morals
PubMed: 35859087
DOI: 10.1007/s11017-022-09578-z -
Best Practice & Research. Clinical... Mar 2022Medically-indicated deliveries are common in twin pregnancies given the increased risk of various obstetric complications in twin compared to singleton pregnancies,... (Review)
Review
Medically-indicated deliveries are common in twin pregnancies given the increased risk of various obstetric complications in twin compared to singleton pregnancies, mainly hypertensive disorders of pregnancy and foetal growth restriction. Due to the unique characteristics of twin pregnancies, the success rates and safety of labour induction may be different than in singleton pregnancies. However, while there are abundant data regarding induction of labour in singleton pregnancies, the efficacy and safety of labour induction in twin pregnancies have been far less studied. In the current manuscript we summarize available data on various aspects of labour induction in twin pregnancies including incidence, success rate, prognostic factors, safety and methods for labour induction in twins. This information may assist healthcare providers in counselling patients with twin pregnancies when labour induction is indicated.
Topics: Female; Fetal Growth Retardation; Humans; Labor, Induced; Labor, Obstetric; Pregnancy; Pregnancy Outcome; Pregnancy, Twin; Twins
PubMed: 34844886
DOI: 10.1016/j.bpobgyn.2021.10.001 -
Best Practice & Research. Clinical... Nov 2022Weight discordance is among the major determinants of perinatal outcome in twin pregnancies. Weight discordance can occur in each trimester of pregnancy, though the... (Review)
Review
Weight discordance is among the major determinants of perinatal outcome in twin pregnancies. Weight discordance can occur in each trimester of pregnancy, though the clinical meaning of such finding and the association with adverse perinatal outcome can vary according to the gestational age (GA) at detection of growth discrepancy. Discrepancy in fetal size in the first trimester of pregnancy is associated with an increased risk of anomalies, aneuploidy, and fetal loss, though the predictive accuracy of using discordance to predict perinatal outcome is low. Conversely, discordance in the third trimester of pregnancy can be associated with fetal growth restriction, perinatal mortality, and morbidity. In view of these associations, twin pregnancies should be monitored for the occurrence of growth discrepancy. The present review aims to provide an up-to-date critical appraisal of the diagnosis and clinical management of twin pregnancies complicated by growth discordance according to the trimester at presentation.
Topics: Pregnancy; Female; Humans; Ultrasonography, Prenatal; Pregnancy, Twin; Fetal Growth Retardation; Gestational Age; Pregnancy Trimester, First; Birth Weight; Pregnancy Outcome
PubMed: 36182539
DOI: 10.1016/j.bpobgyn.2022.08.001