Pre-eclampsia and assisted reproductive technologies: consequences of advanced maternal age, interbirth intervals, new partner and smoking habits

Pre-eclampsia in a Sub-Saharan African country and maternal-perinatal outcome

Our comparative cohort study, carried out between 3^rd January and 30^th April 2020, looked at the maternal and perinatal outcomes associated with pre-eclampsia. Of 2019 booked pregnant women, 141 (7.0%) had pre-eclampsia, and 59.8% of these were severe at admission. Significant adverse maternal outcomes were eclampsia, HELLP (haemolysis, elevated liver enzymes, and low platelets) syndrome, and placental abruption, and significant adverse perinatal outcomes were intra-uterine fetal death, preterm delivery, low birth weight (LBW), neonatal asphyxia and early neonatal death. Close attention needs to be given to women with pre-eclampsia in poor resource circumstances.

To Evaluate the Effect of Increasing Maternal Age on Maternal and Neonatal Outcomes in Pregnancies at Advanced Maternal Age

Introduction

Late pregnancies have been a sensitive issue in the society and medical field for many years. The reason for this development could be the increasing use of reproductive techniques, women empowerment and late conceptions. The increased level of education in women, having more responsibilities at work, giving priority to their professional career could be leading to delay in conception and childbearing. Many studies have investigated the effect of advanced maternal age on fetal outcome suggesting higher risk of poor neonatal outcome. Recent studies have debated these outcomes.[1234].

Aims and Objectives

To evaluate the effect of increasing maternal age on maternal and neonatal outcomes in pregnancies at advanced maternal age.

Material and Methods

The study was conducted on 843 women above the age of 35 years who delivered at Dayanand Medical College and Hospital during 2015-2020. Patients were categorized into 2 groups, Group A comprised of pregnant women aged 35-40 years; group B included pregnant women aged >40 years. Various other parameters including parity, gestation at delivery, whether the pregnancies were spontaneous or conceived through ART (assisted reproductive techniques) and other associated co-morbid conditions were noted. The obstetrical, gynecological, medical, surgical, fetal and neonatal complications were studied in both the groups and the data was analyzed with release 9.4 (SAS Institute Inc, Cary, NC).

Results

Out of 843 patients in our study, 81.4% (n=687) belonged to the age group of 35- 40 years. 18.5% (n=156) belonged to the age group of > 40 years. Patients more than 40 years underwent ART for conception more often as compared to group A. Co-morbid medical conditions including chronic hypertension, thyroid diseases, auto immune disorders and obstetric complications such as abortions, oligohydramnios, GDM, placenta previa, PPH was significantly more common in patients with group B. Cesarean delivery rate was significantly more in group B as compared to group A. Neonatal outcome in terms of NICU admissions and preterm birth at less than 35 weeks gestation was seen more frequently in group B as compared to Group A.

Conclusion

Our study concludes that the decision to delay childbearing should be discouraged owing to increased maternal and fetal morbidity associated with advanced maternal age, the risks being higher with increasing maternal age.

Society for Maternal-Fetal Medicine Consult Series #60: Management of pregnancies resulting from in vitro fertilization

The use of assisted reproductive technology has increased in the United States in the past several decades. Although most of these pregnancies are uncomplicated, in vitro fertilization is associated with an increased risk for adverse perinatal outcomes primarily caused by the increased risks of prematurity and low birthweight associated with in vitro fertilization pregnancies. This Consult discusses the management of pregnancies achieved with in vitro fertilization and provides recommendations based on the available evidence. The recommendations by the Society for Maternal-Fetal Medicine are as follows: (1) we suggest that genetic counseling be offered to all patients undergoing or who have undergone in vitro fertilization with or without intracytoplasmic sperm injection (GRADE 2C); (2) regardless of whether preimplantation genetic testing has been performed, we recommend that all patients who have achieved pregnancy with in vitro fertilization be offered the options of prenatal genetic screening and diagnostic testing via chorionic villus sampling or amniocentesis (GRADE 1C); (3) we recommend that the accuracy of first-trimester screening tests, including cell-free DNA for aneuploidy, be discussed with patients undergoing or who have undergone in vitro fertilization (GRADE 1A); (4) when multifetal pregnancies do occur, we recommend that counseling be offered regarding the option of multifetal pregnancy reduction (GRADE 1C); (5) we recommend that a detailed obstetrical ultrasound examination (CPT 76811) be performed for pregnancies achieved with in vitro fertilization and intracytoplasmic sperm injection (GRADE 1B); (6) we suggest that fetal echocardiography be offered to patients with pregnancies achieved with in vitro fertilization and intracytoplasmic sperm injection (GRADE 2C); (7) we recommend that a careful examination of the placental location, placental shape, and cord insertion site be performed at the time of the detailed fetal anatomy ultrasound, including evaluation for vasa previa (GRADE 1B); (8) although visualization of the cervix at the 18 0/7 to 22 6/7 weeks of gestation anatomy assessment with either a transabdominal or endovaginal approach is recommended, we do not recommend serial cervical length assessment as a routine practice for pregnancies achieved with in vitro fertilization (GRADE 1C); (9) we suggest that an assessment of fetal growth be performed in the third trimester for pregnancies achieved with in vitro fertilization; however, serial growth ultrasounds are not recommended for the sole indication of in vitro fertilization (GRADE 2B); (10) we do not recommend low-dose aspirin for patients with pregnancies achieved with IVF as the sole indication for preeclampsia prophylaxis; however, if 1 or more additional risk factors are present, low-dose aspirin is recommended (GRADE 1B); (11) given the increased risk for stillbirth, we suggest weekly antenatal fetal surveillance beginning by 36 0/7 weeks of gestation for pregnancies achieved with in vitro fertilization (GRADE 2C); (12) in the absence of studies focused specifically on timing of delivery for pregnancies achieved with IVF, we recommend shared decision-making between patients and healthcare providers when considering induction of labor at 39 weeks of gestation (GRADE 1C).

The placenta and preeclampsia: villain or victim?

Preeclampsia is a disease whose characterization has not changed in the 150 years since the cluster of signs associated with the disorder were first described. Although our understanding of the pathophysiology of preeclampsia has advanced considerably since then, there is still little consensus regarding the true etiology of preeclampsia. As a consequence, preeclampsia has earned the moniker "disease of theories," predominantly because the underlying biological mechanisms linking clinical epidemiologic findings to observed organ dysfunction in preeclampsia are far from clear. Despite the lack of cohesive evidence, expert consensus favors the hypothesis that preeclampsia is a primary placental disorder. However, there is now emerging evidence that suboptimal maternal cardiovascular performance resulting in uteroplacental hypoperfusion is more likely to be the cause of secondary placental dysfunction in preeclampsia. Preeclampsia and cardiovascular disease share the same risk factors, preexisting cardiovascular disease is the strongest risk factor (chronic hypertension, congenital heart disease) for developing preeclampsia, and there are now abundant data from maternal echocardiography and angiogenic marker studies that cardiovascular dysfunction precedes the development of preeclampsia by several weeks or months. Importantly, cardiovascular signs and symptoms (hypertension, cerebral edema, cardiac dysfunction) predominate in preeclampsia at clinical presentation and persist into the postnatal period with a 30% risk of chronic hypertension in the decade after birth. Placental malperfusion caused by suboptimal maternal cardiovascular performance may lead to preeclampsia, thereby explaining the preponderance of cardiovascular drugs (aspirin, calcium, statins, metformin, and antihypertensives) in preeclampsia prevention strategies. Despite the seriousness of the maternal and fetal consequences, we are still developing sensitive screening, reliable diagnostic, effective therapeutic, or improvement strategies for postpartum maternal cardiovascular legacy in preeclampsia. The latter will only become clear with an acceptance and understanding of the cardiovascular etiology of preeclampsia.

Assisted reproductive technology and hypertensive disorders of pregnancy: systematic review and meta-analyses

Background

Hypertensive disorders of pregnancy (HDP) is one of the most common pregnancy complications and causes of maternal morbidity and mortality. Assisted reproductive technology (ART) has been associated with adverse pregnancy outcomes, including HDP. However, the impact of multiple pregnancies, oocyte donation, as well as fresh and frozen embryo transfer needs to be further studied. We conducted a systematic review and meta-analyses to evaluate the association between ART and HDP or preeclampsia relative to spontaneous conception (SC).

Methods

We identified studies from EMBASE, MEDLINE, and Cochrane Library (up to April 8, 2020) and manually using structured search strategies. Cohort studies that included pregnancies after in vitro fertilization (IVF) with or without intracytoplasmic sperm fertilization (ICSI) relative to SC with HDP or preeclampsia as the outcome of interest were included. The control group was women who conceived spontaneously without ART or fertility medications. The pooled results were reported in odds ratios (OR) with 95% confidence intervals based on random effects models. Numbers needed to harm (NNH) were calculated based on absolute risk differences between exposure and control groups.

Results

Eighty-five studies were included after a screening of 1879 abstracts and 283 full text articles. Compared to SC, IVF/ICSI singleton pregnancies (OR 1.70; 95% CI 1.60–1.80; I² = 80%) and multiple pregnancies (OR 1.34; 95% CI 1.20–1.50; I² = 76%) were both associated with higher odds of HDP. Singleton pregnancies with oocyte donation had the highest odds of HDP out of all groups analyzed (OR 4.42; 95% CI 3.00–6.51; I² = 83%). Frozen embryo transfer resulted in higher odds of HDP (OR 1.74; 95% CI 1.58–1.92; I² = 55%) than fresh embryo transfer (OR 1.43; 95% CI 1.33–1.53; I² = 72%). The associations between IVF/ICSI pregnancies and SC were similar for preeclampsia. Most interventions had an NNH of 40 to 100, while singleton and multiple oocyte donation pregnancies had particularly low NNH for HDP (16 and 10, respectively).

Conclusions

Our meta-analysis confirmed that IVF/ICSI pregnancies are at higher odds of HDP and preeclampsia than SC, irrespective of the plurality. The odds were especially high in frozen embryo transfer and oocyte donation pregnancies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-03938-8.

Hypertension in Women Across the Lifespan

PURPOSE OF REVIEW

We will highlight the biological processes across a women's lifespan from young adulthood through menopause and beyond that impact blood pressure and summarize women's representation in hypertension clinical trials.

RECENT FINDINGS

Throughout their lifetime, women potentially undergo several unique sex-specific changes that may impact their risk of developing hypertension. Blood pressure diagnostic criteria for pregnant women remains 140/90 mmHg and has not been updated for concordance with the 2017 ACC/AHA guideline due to a lack of data. Although on a population level, women develop hypertension at later ages than men, new data shows women's BP starts to increase as early as the third decade. Understanding how age and sex both contribute to hypertension in elderly women is crucial to identify optimal blood pressure and treatment targets. Effective screening, monitoring, and treatment of hypertension throughout a women's lifespan are necessary to reduce CVD risk. We highlight several gaps in the literature pertaining to understanding sex-specific hypertension mechanisms.

Impact of trophectoderm biopsy on obstetric and perinatal outcomes following frozen-thawed embryo transfer cycles

STUDY QUESTION

Does trophectoderm biopsy for preimplantation genetic testing (PGT) increase the risk of obstetric or perinatal complications in frozen-thawed embryo transfer (FET) cycles?

SUMMARY ANSWER

Trophectoderm biopsy may increase the risk of hypertensive disorders of pregnancy (HDP) in pregnancies following FET cycles.

WHAT IS KNOWN ALREADY

Trophectoderm biopsy has replaced blastomere biopsy as the standard of care to procure cells for PGT analysis. Recently, there has been concern that trophectoderm biopsy may adversely impact obstetric and perinatal outcomes. Previous studies examining this question are limited by use of inappropriate control groups, small sample size or reporting on data that no longer reflects current IVF practice.

STUDY DESIGN, SIZE, DURATION

This was a retrospective cohort study conducted at a single university-affiliated fertility center. A total of 756 patients who underwent FET with transfer of previously vitrified blastocysts that had either trophectoderm biopsy or were unbiopsied and resulted in a singleton live birth between 2013 and 2019 were included.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Obstetric and perinatal outcomes for patients aged 20-44 years who underwent FET with transfer of previously vitrified blastocysts that were either biopsied (n = 241) or unbiopsied (n = 515) were analyzed. Primary outcome was odds of placentation disorders including HDP and rate of fetal growth restriction (FGR). Binary logistic regression was performed to control for potential covariates.

MAIN RESULTS AND THE ROLE OF CHANCE

The biopsy group was significantly older, had fewer anovulatory patients, was more often nulliparous and had fewer embryos transferred compared to the unbiopsied group. After controlling for potential covariates, the probability of developing HDP was significantly higher in the biopsy group compared with unbiopsied group (adjusted odds ratio (aOR) 1.943, 95% CI 1.072-3.521; P = 0.029).There was no significant difference between groups in the probability of placenta previa or placenta accreta. There was also no significant difference in the rate of FGR (aOR 1.397; 95% CI, 0.815-2.395; P = 0.224) or the proportion of low (aOR 0.603; 95% CI, 0.336-1.084; P = 0.091) or very low (aOR 2.948; 95% CI, 0.613-14.177; P = 0.177) birthweight infants comparing biopsied to unbiopsied groups.

LIMITATIONS, REASON FOR CAUTION

This was a retrospective study performed at a single fertility center, which may limit the generalizability of our findings.

WIDER IMPLICATIONS OF THE FINDINGS

Trophectoderm biopsy may increase the risk of HDP in FET cycles, however, a prospective multicenter randomized trial should be performed to confirm these findings.

STUDY FUNDING/COMPETING INTEREST(S)

No specific funding was obtained for this study. The authors declare no conflict of interest.

TRIAL REGISTRATION NUMBER

NA.

Is ovarian response associated with adverse perinatal outcomes in GnRH antagonist IVF/ICSI cycles?

RESEARCH QUESTION

Is there an association between ovarian response and perinatal outcomes?

DESIGN

A retrospective, single-centre cohort study including all women undergoing their first ovarian stimulation cycle in a gonadotrophin releasing hormone antagonist protocol, with a fresh embryo transfer that resulted in a singleton live birth from January 2009 to December 2015. Patients were categorized into four groups according to the number of oocytes retrieved: one to three (category 1), four to nine (category 2), 10-15 (category 3), or over 15 oocytes (category 4).

RESULTS

The overall number of patients analysed was 964. No relevant statistical difference was found among neonatal outcomes across the four ovarian response categories. Neonatal weight (in grams) was comparable between all groups (3222 ± 607 versus 3254 ± 537 versus 3235 ± 575 versus 3200 ± 622; P = 0.85, in categories 1, 2, 3 and 4, respectively). No statistically significant differences were found among the ovarian response categories for birth weight z-scores (taking into account neonatal sex and delivery term). The incidence of pre-term birth and low birth weight was comparable across the different ovarian response groups (P = 0.127 and P = 0.19, respectively). Finally, the occurrence of adverse obstetric outcomes did not differ among the ovarian response categories. Multivariate regression analysis revealed that the number of oocytes was not associated with neonatal birth weight.

CONCLUSIONS

No association was found between ovarian response and adverse perinatal outcomes in antagonist IVF and intracytoplasmic sperm injection cycles. Future, larger scale and prospectively designed investigations are needed to validate these results.

Maternal and perinatal outcomes in programmed versus natural vitrified-warmed blastocyst transfer cycles

RESEARCH QUESTION

Do maternal and perinatal outcomes differ between natural and programmed frozen embryo transfer (FET) cycles?

DESIGN

Retrospective cohort study at a university-affiliated fertility centre including 775 patients who underwent programmed or natural FET cycles resulting in a singleton live birth using blastocysts vitrified between 2013 and 2018.

RESULTS

A total of 384 natural and 391 programmed FET singleton pregnancies were analysed. Programmed FET resulted in higher overall maternal complications (32.2% [126/391] versus 18.8% [72/384]; P < 0.01), including higher probability of hypertensive disorders of pregnancy (HDP) (15.3% [60/391] versus 6.3% [24/384]; P < 0.01), preterm premature rupture of membranes (2.6% [10/391] versus 0.3% [1/384]; P = 0.02) and caesarean delivery (53.2% [206/387] versus 42.8% [163/381]; P = 0.03) compared with natural FET. After controlling for potential confounders, including age, body mass index, parity, smoking status, history of diabetes or chronic hypertension, infertility diagnosis, number of embryos transferred and use of preimplantation genetic testing, the adjusted odds ratio for HDP was 2.39 (95% CI 1.37 to 4.17) and for overall maternal complications was 2.21 (95% CI 1.51 to 3.22) comparing programmed with natural FET groups. The groups did not significantly differ for any perinatal outcomes analysed, including birth weight (3357.9 ± 671.6 g versus 3318.4 ± 616.2 g; P = 0.40) or rate of birth defects (1.5% [6/391] versus 2.1% [8/384]; P = 0.57), respectively.

CONCLUSION

Vitrified-warmed blastocyst transfer in a programmed cycle resulted in a twofold higher probability of HDP compared with transfer in a natural cycle. Natural FET cycle should, therefore, be recommended as first line for all eligible patients undergoing FET to reduce the risk of HDP.

Frozen-thawed embryo transfer: the potential importance of the corpus luteum in preventing obstetrical complications

The use of frozen-thawed embryo transfer (FET) has increased over the past decade with improvements in technology and increasing live birth rates. FET facilitates elective single-embryo transfer, reduces ovarian hyperstimulation syndrome, optimizes endometrial receptivity, allows time for preimplantation genetics testing, and facilitates fertility preservation. FET cycles have been associated, however, with an increased risk of hypertensive disorders of pregnancy for reasons that are not clear. Recent evidence suggests that absence of the corpus luteum (CL) could be at least partly responsible for this increased risk. In a recent prospective cohort study, programmed FET cycles (no CL) were associated with higher rates of preeclampsia and preeclampsia with severe features compared with modified natural FET cycles. FET cycles are commonly performed in the context of a programmed cycle in which the endometrium is prepared with the use of exogenous E2 and P. In these cycles, ovulation is suppressed and therefore the CL is absent. The CL produces not only E2 and P, but also vasoactive products, such as relaxin and vascular endothelial growth factor, which are not replaced in a programmed FET cycle and which are hypothesized to be important for initial placentation. Emerging evidence has also revealed other adverse obstetrical and perinatal outcomes, including postpartum hemorrhage, macrosomia, and post-term birth specifically in programmed FET cycles compared with natural FET cycles. Despite the widespread use of FET, the optimal protocol with respect to live birth rate, maternal health, and perinatal outcomes has yet to be determined. Future practice regarding FET should be based on high-quality evidence, including rigorous controlled trials.

Increased Preeclampsia Risk and Reduced Aortic Compliance With In Vitro Fertilization Cycles in the Absence of a Corpus Luteum

In vitro fertilization involving frozen embryo transfer and donor oocytes increases preeclampsia risk. These in vitro fertilization protocols typically yield pregnancies without a corpus luteum (CL), which secretes vasoactive hormones. We investigated whether in vitro fertilization pregnancies without a CL disrupt maternal circulatory adaptations and increase preeclampsia risk. Women with 0 (n=26), 1 (n=23), or >1 (n=22) CL were serially evaluated before, during, and after pregnancy. Because increasing arterial compliance is a major physiological adaptation in pregnancy, we assessed carotid-femoral pulse wave velocity and transit time. In a parallel prospective cohort study, obstetric outcomes for singleton livebirths achieved with autologous oocytes were compared between groups by CL number (n=683). The expected decline in carotid-femoral pulse wave velocity and rise in carotid-femoral transit time during the first trimester were attenuated in the 0-CL compared with combined single/multiple-CL cohorts, which were similar (group-time interaction: P=0.06 and 0.03, respectively). The blunted changes of carotid-femoral pulse wave velocity and carotid-femoral transit time from prepregnancy in the 0-CL cohort were most striking at 10 to 12 weeks of gestation ( P=0.01 and 0.006, respectively, versus 1 and >1 CL). Zero CL was predictive of preeclampsia (adjusted odds ratio, 2.73; 95% CI, 1.14-6.49) and preeclampsia with severe features (6.45; 95% CI, 1.94-25.09) compared with 1 CL. Programmed frozen embryo transfer cycles (0 CL) were associated with higher rates of preeclampsia (12.8% versus 3.9%; P=0.02) and preeclampsia with severe features (9.6% versus 0.8%; P=0.002) compared with modified natural frozen embryo transfer cycles (1 CL). In common in vitro fertilization protocols, absence of the CL perturbed the maternal circulation in early pregnancy and increased the incidence of preeclampsia.

Impact of the mode of conception on gestational hypertensive disorders at very advanced maternal age

RESEARCH QUESTION

To study gestational hypertensive disorders in oocyte donation pregnancies compared with other modes of conception at very advanced maternal age.

DESIGN

A historical cohort study of all women aged 45-47 years who gave birth to singletons at a tertiary medical centre between March 2011 and May 2018, at 24 weeks' gestation or later. Pregnancy outcomes were compared between donor oocyte (IVF-OD), IVF using autologous oocytes (IVF-A) and naturally conceived pregnancies. A multivariate logistic regression was used to evaluate the association between the mode of conception and gestational hypertensive disorders.

RESULTS

The final analysis included 159, 68 and 73 patients in the IVF-OD, IVF-A and natural conception groups, respectively. The rate of gestational hypertensive disorders was significantly higher among those who conceived by IVF compared with those who conceived naturally but did not differ between the two IVF groups (27.0% for IVF-OD, 19.1% for IVF-A, P = 0.204; 5.5% for natural conception, P < 0.001 and P = 0.013 compared with IVF-OD and IVF-A, respectively). The results remained similar in a multivariate logistic regression analysis. The rate of Caesarean deliveries was significantly higher in the IVF-OD and IVF-A groups compared with the natural conception group (83.6%, 70.6% and 37.0%, respectively, P < 0.001), but other pregnancy outcomes did not differ between the groups.

CONCLUSIONS

IVF pregnancies in the late fifth decade of life were associated with significantly higher rates of gestational hypertensive disorders compared with naturally conceived pregnancies. No difference existed between the two IVF groups. These results may highlight the impact of IVF itself on gestational hypertensive disorders at very advanced maternal age.

In vitro fertilization is associated with the onset and progression of preeclampsia

OBJECTIVE

We aimed to estimate the risk of preeclampsia (PE) associated with in vitro fertilization (IVF) and potential predisposing factors responsible for the observed association.

METHODS

This retrospective cohort study included 114485 pregnant women who delivered at the Nanjing Maternity and Child Health Care Hospital between 2013 and 2018. Of the 114485 women, 4601 (4%) conceived through IVF (IVF group) and 109884 (96%) conceived spontaneously (SC group). We performed logistic regression analysis to evaluate the risk of PE following IVF compared to spontaneous conception (SC). Then, we used propensity score matching analysis to compare the clinical characteristics and pregnancy outcomes between IVF patients with and without PE.

RESULT

There were 1339 PE cases in the total study population, with a significantly higher incidence of PE in IVF relative to spontaneous pregnancies (6.1% vs. 1.0%, p < 0.01). Severe PE was more prevalent in singleton IVF-PE group than in singleton SC-PE group (40% vs. 24.1%, p = 0.025). Placenta accreta was more common in singleton preeclamptic patients with IVF than without IVF (12.5vs.2.6%, p = 0.003). Placental hypoxia was more prevalent in twin IVF pregnancies with PE than without PE (6% vs. 12.2%, p = 0.045). Moreover, the IVF-PE group showed more frequent first-trimester bleeding (31.6% vs. 10.5%, p = 0.024) compared to the control group.

CONCLUSION

IVF is associated with the onset and progression of PE. Defective placentation and placental insufficiency may predispose IVF patients to PE and may manifest as first-trimester bleeding.

Preeclampsia: The Relationship between Uterine Artery Blood Flow and Trophoblast Function

Maternal uterine artery blood flow is critical to maintaining the intrauterine environment, permitting normal placental function, and supporting fetal growth. It has long been believed that inadequate transformation of the maternal uterine vasculature is a consequence of primary defective trophoblast invasion and leads to the development of preeclampsia. That early pregnancy maternal uterine artery perfusion is strongly associated with placental cellular function and behaviour has always been interpreted in this context. Consistently observed changes in pre-conceptual maternal and uterine artery blood flow, abdominal pregnancy implantation, and late pregnancy have been challenging this concept, and suggest that abnormal placental perfusion may result in trophoblast impairment, rather than the other way round. This review focuses on evidence that maternal cardiovascular function plays a significant role in the pathophysiology of preeclampsia.

Assisted reproductive technology and the risk of preeclampsia: an updated systematic review and meta-analysis

Background

The objective of this systematic review and meta-analyses was to assess the risk of preeclampsia among women who conceived with assisted reproductive technology (ART).

Methods

We searched the ISI Web of Knowledge, Medline/PubMed, Scopus, and Embase (from inception to May 2017) for English language articles using a list of key words. In addition, reference lists from identified studies and relevant review articles were also searched. Data extraction was performed by two authors, and the study quality was assessed using the Newcastle–Ottawa Scale. Random-effects model meta-analysis was applied to pool the relative risks (RR) across studies.

Results

A total of 48 studies (5 case-control studies and 43 cohort studies) were included in this meta-analysis. The Cochran Q test and I² statistics revealed substantial heterogeneity (Q = 26,313.92, d.f. = 47, p < 0.001 and I² = 99.8%). Meta-analysis showed a significant increase in preeclampsia in women who conceived by ART compared with those who conceived spontaneously (RR = 1.71, 95% CI = 1.11–2.62, p = 0.015).

Conclusions

The findings of this systematic review indicate that the use of ART treatment is associated with a 1.71-fold increase in preeclampsia.

Singleton fetal growth kinetics depend on the mode of conception

OBJECTIVE

To study the impact of in vitro fertilization, with or without intracytoplasmic sperm injection (IVF/ICSI), frozen-embryo transfer (FET), and intrauterine insemination (IUI) on fetal growth kinetics throughout pregnancy and to compare the different modes of conception.

DESIGN

Retrospective cohort study.

SETTING

University.

PATIENT(S)

A total of 560 singleton pregnancies were included (96 IVF, 210 ICSI, 121 FET, and 133 IUI).

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

We compared crown-rump length (CRL) at the first trimester (T1: 11-13 weeks of gestation [WG] + 6 days), estimated fetal weight (EFW) at the second (T2: 21-23 WG + 6 days) and third (T3: 31-33 WG + 6 days) trimesters, and birth weight (BW) z-scores with those in the reference curves (Papageorghiou for T1, and Ego M2 for T2, T3, and birth). Multivariate analyses were performed.

RESULT(S)

For T1, the CRL was longer than the reference curve whatever the assisted reproductive technique (ART). For T2, EFW was significantly greater for all groups compared with the reference curve, and for T3 only FET singletons had a greater EFW. ICSI, IVF, and IUI singletons had a significantly lower BW compared with reference curves. For all ART fetuses, growth kinetics differed from T2. Only FET fetuses maintained their significantly above-reference growth values. The proportion of fetuses for which at least one period of growth loss was observed from T2 to birth was higher after IVF, ICSI, and IUI than after FET.

CONCLUSION(S)

For the first time, we have highlighted that fetal growth kinetics differed from T2 depending on the ART protocols used. They could have an impact on trophoblastic invasiveness and might lead to long-term health effects.

Risk of preeclampsia following assisted reproductive technology: systematic review and meta-analysis of 72 cohort studies

Objective: Previous studies have indicated that women with assisted reproductive technology (ART) pregnancy have an increased risk of preeclampsia. The aim of this current study was to estimate, through a systematic review and meta-analysis of cohort studies, the risk of preeclampsia in women who conceived with ART.Materials and methods: We searched ISI Web of Knowledge, Medline/PubMed, Scopus and Embase up to August 2017 for English-language articles pertaining to risk of preeclampsia in ART pregnancy using standard keywords. Data extraction was conducted by two authors and quality of the studies was assessed using the Newcastle-Ottawa Scale. A random-effects model was used for the meta-analysis.Results: In total, 72 cohort studies (n = 164 870) were included. The results of Cochran test and I² statistic indicated considerable heterogeneity among studies (Q = 15 415.61, df = 71, p < .001, I²=99.5%). The pooled estimate of preeclampsia risk using the random effects model was 10.8% (95% CI: 9.10-12.5). Furthermore, the funnel plot and Begg's test showed evidence of publication bias.Conclusions: We found that the risk of preeclampsia was very high among women who conceived with ART. Women should be counseled carefully before undergoing ART treatment.

Obstetric and perinatal outcomes of singleton pregnancies conceived via assisted reproductive technology complicated by gestational diabetes mellitus: a prospective cohort study

Background

Growing evidence indicates that the risk of obstetric and perinatal outcomes is higher in women with assisted reproductive technology (ART). However, there is little known about pregnancy related complications and co-morbidity in gestational diabetes mellitus (GDM) following singleton pregnancies achieved by ART in comparison with spontaneous conception (SC).

Methods

Two hundred sixty singleton pregnant women conceived by ART and 314 pregnant women conceived by spontaneous conception (SC) were participated in this prospective cohort study. All participants were enrolled after GDM screening through one-step oral glucose tolerance test (OGTT) and then grouped into GDM and non-GDM groups. Women were followed for pregnancy outcomes including pregnancy-induced hypertension (PIH), preeclampsia, antepartum hemorrhage (APH), cesarean section (CS), preterm birth (PTB), intrauterine growth restriction (IUGR), being small or large for gestational age (SGA or LGA), macrosomia, low birth weight (LBW), respiratory distress, neonatal hypoglycemia, NICU admission and perinatal mortality from antenatal visits to delivery. Confounding factors were adjusted in logistic regression model in order to estimate adjusted odds ratios (aORs).

Results

Among 260 ART and 314 SC, 135 and 152 women were GDM women, respectively. Higher maternal age and pre-gravid BMI, shorter duration of gestation and lower gestational weight gain were observed in GDM groups (ART-GDM and SC-GDM) compared to those of the SC group. ART-GDM group had a higher risk (95% confidence interval) of obstetric complications including PIH [aOR:7.04 (2.24–22.15)], preeclampsia [aOR:7.78 (1.62–37.47)], APH [aOR:3.46 (1.28–9.33)], emergency CS [aOR:2.64 (1.43–4.88)], and perinatal outcomes such as PTB [aOR:3.89 (1.51–10.10)], LBW [aOR:3.11 (1.04–9.30)] and NICU admission [aOR:4.36 (1.82–10.45)], as well as neonatal hypoglycemia [aOR: 4.91 (1.50–16.07)], compared to SC group. SC-GDM group showed a higher risk of PIH [aOR: 4.12 (1.31–12.89)], emergency CS [aOR: 2.01 (1.09–3.73] and LGA [aOR: 5.20 (1.07–25.20)], compared to SC group. Additionally, ART group had a higher risk of PIH [aOR: 3.46(1.02–11.68), preeclampsia 5.29 (1.03–27.09), and NICU admission [aOR: 2.53 (1.05–6.09)] compared to SC. Insulin requirement (41.8% vs. 25.7%) was significantly higher in ART-GDM group compared to SC-GDM group.

Conclusion

The findings of this study suggest that GDM occurring after ART conception increases the risk of adverse obstetric and perinatal outcomes.

Family Planning and Pregnancy Management in Adults with Congenital Heart Disease

With advances in congenital heart disease management, there are an increasing number of women reaching reproductive age. Pregnancy results in a surge of hormones and increased demands on both the cardiovascular (CV) and respiratory systems. Depending on the heart defect and the treatments the mother has undergone, these hemodynamic changes can result in an increased risk of maternal CV events and an increased risk of fetal morbidity and mortality. Thus, it is important to have a comprehensive approach to adult congenital heart disease patients involving pre-pregnancy planning in addition to diligent peri- and post-partum care.

Immunological Tolerance, Pregnancy, and Preeclampsia: The Roles of Semen Microbes and the Father

Although it is widely considered, in many cases, to involve two separable stages (poor placentation followed by oxidative stress/inflammation), the precise originating causes of preeclampsia (PE) remain elusive. We have previously brought together some of the considerable evidence that a (dormant) microbial component is commonly a significant part of its etiology. However, apart from recognizing, consistent with this view, that the many inflammatory markers of PE are also increased in infection, we had little to say about immunity, whether innate or adaptive. In addition, we focused on the gut, oral and female urinary tract microbiomes as the main sources of the infection. We here marshall further evidence for an infectious component in PE, focusing on the immunological tolerance characteristic of pregnancy, and the well-established fact that increased exposure to the father's semen assists this immunological tolerance. As well as these benefits, however, semen is not sterile, microbial tolerance mechanisms may exist, and we also review the evidence that semen may be responsible for inoculating the developing conceptus (and maybe the placenta) with microbes, not all of which are benign. It is suggested that when they are not, this may be a significant cause of PE. A variety of epidemiological and other evidence is entirely consistent with this, not least correlations between semen infection, infertility and PE. Our view also leads to a series of other, testable predictions. Overall, we argue for a significant paternal role in the development of PE through microbial infection of the mother via insemination.

Age at menarche and the risk of operative delivery

OBJECTIVES

We sought to evaluate the impact of later menarche on the risk of operative delivery.

POPULATION

We studied 38,069 eligible women (first labors at term with a singleton infant in a cephalic presentation) from the Norwegian Mothers and Child Cohort Study. The main exposures were the age at menarche and the duration of the interval between menarche and the first birth.

METHODS

Poisson's regression with a robust variance estimator.

MAIN OUTCOME MEASURES

Operative delivery, defined as emergency cesarean or assisted vaginal delivery (ventouse extraction or forceps).

RESULTS

A 5 year increase in age at menarche was associated with a reduced risk of operative delivery (risk ratio [RR] 0.84, 95%CI 0.78, 0.89; p < .001). Adjustment for the age at first birth slightly strengthened the association (RR 0.79, 95%CI 0.74, 0.84; p < .001). However, the association was lost following adjustment for the menarche to birth interval (RR 0.99, 95%CI 0.93, 1.06; p = .81). A 5 years increase in menarche to birth interval was associated with an increased risk of operative delivery (RR 1.26, 95%CI 1.23, 1.28; p < .001). This was not materially affected by adjustment for an extensive series of maternal characteristics (RR 1.23, 95%CI 1.20, 1.25; p < .001).

CONCLUSIONS

Later menarche reduces the risk of an operative first birth through shortening the menarche to birth interval. This observation is consistent with the hypothesis that the pattern and/or duration of prepregnancy exposure of the uterus to estrogen and progesterone contributes to uterine aging.

Immunological implications of pregnancy-induced microchimerism

Immunological identity is traditionally defined by genetically encoded antigens, with equal maternal and paternal contributions as a result of Mendelian inheritance. However, vertically transferred maternal cells also persist in individuals at very low levels throughout postnatal development. Reciprocally, mothers are seeded during pregnancy with genetically foreign fetal cells that persist long after parturition. Recent findings suggest that these microchimeric cells expressing non-inherited, familially relevant antigenic traits are not accidental 'souvenirs' of pregnancy, but are purposefully retained within mothers and their offspring to promote genetic fitness by improving the outcome of future pregnancies. In this Review, we discuss the immunological implications, benefits and potential consequences of individuals being constitutively chimeric with a biologically active 'microchiome' of genetically foreign cells.

A best practice position statement on the role of the nephrologist in the prevention and follow-up of preeclampsia: the Italian study group on kidney and pregnancy

Preeclampsia (PE) is a protean syndrome causing a transitory kidney disease, characterised by hypertension and proteinuria, ultimately reversible after delivery. Its prevalence is variously estimated, from 3 to 5% to 10% if all the related disorders, including also pregnancy-induced hypertension (PIH) and HELLP syndrome (haemolysis, increase in liver enzyme, low platelets) are included. Both nephrologists and obstetricians are involved in the management of the disease, according to different protocols, and the clinical management, as well as the role for each specialty, differs worldwide. The increased awareness of the role of chronic kidney disease in pregnancy, complicating up to 3% of pregnancies, and the knowledge that PE is associated with an increased risk for development of CKD later in life have recently increased the interest and redesigned the role of the nephrologists in this context. However, while the heterogeneous definitions of PE, its recent reclassification, an emerging role for biochemical biomarkers, the growing body of epidemiological data and the new potential therapeutic interventions lead to counsel long-term follow-up, the lack of resources for chronic patients and the increasing costs of care limit the potential for preventive actions, and suggest tailoring specific interventional strategies. The aim of the present position statement of the Kidney and Pregnancy Study Group of the Italian Society of Nephrology is to review the literature and to try to identify theoretical and pragmatic bases for an agreed management of PE in the nephrological setting, with particular attention to the prevention of the syndrome (recurrent PE, presence of baseline CKD) and to the organization of the postpartum follow-up.

Vitrified-warmed single-embryo transfers may be associated with increased maternal complications compared with fresh single-embryo transfers

Cryopreservation of embryos allows single-embryo transfer and storage of supernumerary embryos, maximizing cumulative pregnancy rates. The purpose of this retrospective cohort study was to compare pregnancy outcome in singletons born after fresh or vitrified-warmed single blastocyst transfer (SBT). Singleton live births resulting from SBT of fresh or vitrified-warmed embryos were compared. Primary outcomes were perinatal outcomes including small for gestational age (SGA), low birthweight, preterm deliveries (PTD), large for gestational age (LGA) and congenital malformations. Maternal complications included pre-eclampsia, placenta previa, placental abruption, gestational diabetes mellitus (GDM) and chorioamnionitis. Adjustment for confounding factors was performed. Of 1886 fresh SBTs and 1200 vitrified-warmed SBTs during the study period, vitrified-warmed SBTs compared with fresh SBTs resulted in significantly lower clinical pregnancy rate (P < 0.0001). Live birth and miscarriage rates calculated only for pregnancy with known outcome revealed lower live birth rates and higher miscarriage rates for the vitrified-warmed group. Perinatal complications were calculated for clinical pregnancies with known outcomes (12.9% catchment failure was excluded from analysis). The vitrified-warmed group showed a trend toward higher rates of pre-eclampsia, GDM, Caesarean delivery and LGA neonates. Rates of PTD and SGA were comparable. In conclusion, vitrified-warmed SBT might be associated with increased feto-maternal complications.

Perinatal and obstetric outcomes of dichorionic vs trichorionic triplet pregnancies

BACKGROUND

Clinical management and outcome of multiple gestation can be affected by chorionicity. In triplet pregnancies, fetal death has been associated with dichorionic (DC) and monochorionic placentation. Studies evaluating triplet pregnancy outcomes in relation to chorionicity have been few and may not reflect contemporary antenatal and neonatal care.

OBJECTIVE

The objective of this study was to compare obstetric and perinatal outcomes in DC and trichorionic (TC) triplet pregnancies.

STUDY DESIGN

We performed a retrospective cohort study of triplet pregnancies that delivered at ≥20 weeks' gestation at 2 Chicago area hospitals from January 1999 through December 2010. Chorionicity was determined by pathology specimen. Maternal and infant charts were reviewed for obstetric and perinatal outcomes.

RESULTS

The study population included 159 pregnancies (477 neonates) of which 108 were TC (67.9%) and 51 were DC (32.1%). Over 94% of mothers in this study had all 3 infants survive to discharge regardless of chorionicity. No difference was found in perinatal mortality rate between DC and TC triplets (3.3% vs 4.6%; P = .3). DC triplets were significantly more likely to be very low birthweight (41.8% vs 22.2%; odds ratio, 2.2; 95% confidence interval, 1.2-4.2; P = .02) and to deliver at <30 weeks (25.5% vs 8.3%; odds ratio, 6.1; 95% confidence interval, 1.9-19.4; P = .002) compared to TC triplets. Criteria for twin-twin transfusion syndrome (TTTS) were present in 3 DC triplet pregnancies (5.9%). Neonates in pregnancies complicated by TTTS were less likely to survive 28 days as compared to neonates from DC pregnancies that were not affected by TTTS (P = .02) or TC neonates (P = .02) Neonatal survival was similar in DC pregnancies not affected by TTTS and TC pregnancies (98.6% and 96.6%; P = .7).

CONCLUSION

Although perinatal mortality did not correlate with chorionicity, DC pregnancies were more likely to deliver <30 weeks' gestational age and have very low birthweight neonates. Neonatal mortality appears to be mediated by the presence or absence of TTTS as 28-day survival was worse in DC pregnancies complicated by TTTS, but similar between DC pregnancies not affected by TTTS and TC pregnancies.

Clinical risk factors for pre-eclampsia determined in early pregnancy: systematic review and meta-analysis of large cohort studies

OBJECTIVE

To develop a practical evidence based list of clinical risk factors that can be assessed by a clinician at ≤ 16 weeks' gestation to estimate a woman's risk of pre-eclampsia.

DESIGN

Systematic review and meta-analysis of cohort studies.

DATA SOURCES

PubMed and Embase databases, 2000-15.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Cohort studies with ≥ 1000 participants that evaluated the risk of pre-eclampsia in relation to a common and generally accepted clinical risk factor assessed at ≤ 16 weeks' gestation.

DATA EXTRACTION

Two independent reviewers extracted data from included studies. A pooled event rate and pooled relative risk for pre-eclampsia were calculated for each of 14 risk factors.

RESULTS

There were 25,356,688 pregnancies among 92 studies. The pooled relative risk for each risk factor significantly exceeded 1.0, except for prior intrauterine growth restriction. Women with antiphospholipid antibody syndrome had the highest pooled rate of pre-eclampsia (17.3%, 95% confidence interval 6.8% to 31.4%). Those with prior pre-eclampsia had the greatest pooled relative risk (8.4, 7.1 to 9.9). Chronic hypertension ranked second, both in terms of its pooled rate (16.0%, 12.6% to 19.7%) and pooled relative risk (5.1, 4.0 to 6.5) of pre-eclampsia. Pregestational diabetes (pooled rate 11.0%, 8.4% to 13.8%; pooled relative risk 3.7, 3.1 to 4.3), prepregnancy body mass index (BMI) >30 (7.1%, 6.1% to 8.2%; 2.8, 2.6 to 3.1), and use of assisted reproductive technology (6.2%, 4.7% to 7.9%; 1.8, 1.6 to 2.1) were other prominent risk factors.

CONCLUSIONS

There are several practical clinical risk factors that, either alone or in combination, might identify women in early pregnancy who are at "high risk" of pre-eclampsia. These data can inform the generation of a clinical prediction model for pre-eclampsia and the use of aspirin prophylaxis in pregnancy.

Pre-eclampsia and first-onset postpartum psychiatric episodes: a Danish population-based cohort study

BACKGROUND

Recent evidence suggests that postpartum psychiatric episodes may share similar etiological mechanisms with immune-related disorders. Pre-eclampsia is one of the most prevalent immune-related disorders of pregnancy. Multiple clinical features are shared between pre-eclampsia and postpartum psychiatric disorders, most prominently a strong link to first pregnancies. Therefore, we aimed to study if pre-eclampsia is a risk factor for first-onset postpartum psychiatric episodes.

METHOD

We conducted a cohort study using the Danish population registry, with a total of 400 717 primiparous women with a singleton delivery between 1995 and 2011. First-lifetime childbirth was the main exposure variable and the outcome of interest was first-onset postpartum psychiatric episodes. The main outcome measures were monthly incidence rate ratios (IRRs), with the period 11-12 months after birth as the reference category. Adjustments were made for age, calendar period, reproductive history, and perinatal maternal health including somatic and obstetric co-morbidity.

RESULTS

Primiparous women were at particularly high risk of first-onset psychiatric episodes during the first month postpartum [IRR 2.93, 95% confidence interval (CI) 2.53-3.40] and pre-eclampsia added to that risk (IRR 4.21, 95% CI 2.89-6.13). Having both pre-eclampsia and a somatic co-morbidity resulted in the highest risk of psychiatric episodes during the 3-month period after childbirth (IRR 4.81, 95% CI 2.72-8.50).

CONCLUSIONS

We confirmed an association between pre-eclampsia and postpartum psychiatric episodes. The possible explanations for this association, which are not mutually exclusive, include the psychological impact of a serious medical condition such as pre-eclampsia and the neurobiological impact of pre-eclampsia-related vascular pathology and inflammation.