First Weeks Of Pregnancy Research Articles

P701 Usefulness of echocardiography in diagnosis and monitoring in patient with pulmonary embolism during pregnancy, a case report

Abstract Pulmonary embolism is one of the leading causes of maternal mortality despite a low incidence of during pregnancy. We present 32-year-old woman, in the 35 week of first pregnancy, admitted to the Intensive Care Unit with dyspnea, tachycardia, cyanosis. Echocardiography confirmed the presence of embolic material in the main trunk of pulmonary artery, spreading to the right pulmonary artery. D-dimer and troponin T level were elevated, BNP remained within the normal range. The risk in PESI scale was assumed as intermediate high. LMWH therapy was initiated, the patient was constantly monitored. Venous thrombotic disease in lower extremities was excluded by ultrasonography. The treatment was carried out under obstetric supervision. The clinical state gradually improved, the patient was hemodynamically stable. Serial echocardiographic testing, revealed gradual regression of changes in the pulmonary trunk. Normalization of troponins and lowering of BNP levels were observed. The pregnancy was terminated in 39 week, by cesarean section (obstetric indications). The LMWH was continued few days after delivery, as the patient started lactation. She decided to terminate lactation in a first week after delivery so the therapy was switched into rivaroxaban for at least 3 months. Echocardiography after 3 month confirmed lack of changes in pulmonary trunk, the risk of pulmonary hypertension was low. Echocardiography can be a method of choice for confirming and monitoring pulmonary embolism during pregnancy, in a situation of high or intermediate clinical risk and good visualization of changes in pulmonary arteries Abstract P701 Figure. Embolism of pulmonary trunk and RPA

Pregnancy duration and endometrial cancer risk: nationwide cohort study

ObjectiveTo explore the association between pregnancy duration and risk of endometrial cancer.DesignNationwide register based cohort study.SettingDenmark.ParticipantsAll Danish women born from 1935 to 2002.Main outcome measuresRelative risk (incidence rate ratio) of...

Prevention of miscarriage following ovulation induction in women with endocrine infertility in anamnesis

Prescription of adjusted maintenance hormonal therapy during early stages of induced pregnancy is one of the most effective means of reducing reproductive losses.Aim. To improve the maintenance hormonal therapy during early stages of induced pregnancy in patients with endocrine infertility of various genesis in anamnesis.Materials and methods. In total, 44 women with induced singleton pregnancy and anovulatory infertility in anamnesis and 20 healthy pregnant women underwent ultrasound and hormonal monitoring during the first trimester of pregnancy. Depending on the dynamics of hormonal changes, corrective hormonal therapy was prescribed for patients with induced pregnancy. Prolongation of pregnancy up to 12 weeks was considered to be the main criterion for the evaluation of the therapeutic measures effectiveness. Statistical processing of data was performed using the programs StatSoft Statistica v.6.0, Microsoft Excel XP.Results. Despite the exogenous administration of progestins in the group of women with anovulatory infertility in anamnesis, there were detected high risks of miscarriage (47.7 %), chorionic pathology (29.5 %), abortions (27.3 %). Hormonal monitoring in patients with termination of pregnancy and hypothalamic-pituitary insufficiency revealed an initially low level of β-hCG, normal level of progesterone but an inadequate their rise in dynamics; in patients with hyperprolactinemia – a very high concentration of progesterone, normal β-hCG level in early gestation and its gradual decrease during the first trimester; in patients with hyperandrogenemia – a very high concentration of progesterone at the beginning and progressive its decrease during the first trimester, inadequate rise of β-hCG from the beginning of the study combined with increased levels of androgens – dehydroepiandrostenediol sulfate and/or free testosterone.Conclusions. In order to select an appropriate maintenance hormonal therapy, the concentration of progesterone and β-hCG should be determined at the beginning of the first trimester in patients with induced pregnancy and endocrine infertility in anamnesis. The first weeks of gestation (hyperconcentration of hormones) and the middle of the first trimester (corpus luteum regression) are the critical periods for such pregnant women. An adequate rise of β-hCG with normal or increased level of progesterone in women with hyperandrogenism and hyperprolactinemia during the first weeks of pregnancy serves as a reason for withdrawal of exogenous progesterone administration with a possible prolonged therapy after 6–7 weeks of gestation under the dynamic control of progesterone and β-hCG levels. Patients with hypothalamic-pituitary insufficiency should receive constant maintenance hormonal therapy with progestins in high therapeutic doses at the beginning of pregnancy.

Embryonic extracellular vesicles as informers to the immune cells at the maternal-fetal interface.

Extracellular vesicle (EV) exchange is emerging as a novel method of communication at the maternal-fetal interface. The presence of the EVs has been demonstrated in the preimplantation embryo culture medium from different species, such as bovines, porcines and humans. Preimplantation embryo-derived EVs have been shown to carry molecules potentially able to modulate the local endometrial immune system. The non-classical major histocompatibility complex (MHC) class I molecule human leucocyte antigen (HLA)-G, the immunomodulatory molecule progesterone-induced blocking factor and some regulatory miRNAs species are contained in embryo-derived EV cargo. The implanted syncytiotrophoblasts are also well known to secrete EVs, with microvesicles exerting a mainly proinflammatory effect while exosomes in general mediate local immunotolerance. This review focuses on the current knowledge on the potential role of EVs released by the embryo in the first weeks of pregnancy on the maternal immune cells. Collectively, the data warrant further exploration of the dialogue between the mother and the embryo via EVs.

Management of thyroid disorders during and after pregnancy

Сучасний огляд нещодавніх рекомендацій Американської тиреоїдної асоціації та Ендокринного товариства США висвітлює найважливіші питання обстеження та ведення пацієнток із захворюваннями щитоподібної залози на тлі вагітності. Показано, що не тільки вагітність впливає на перебіг тиреоїдної патології, але й функціональні зміни тиреоїдного гормоногенезу становлять серйозну проблему для матері та плода. У вагітних під впливом плацентарного хоріонічного гонадотропіну рівень тиреотропного гормону значно знижується на 0,1–0,4 мкМО/мл для нижньої межі норми та на 1,0 мкМО/мл для верхньої у I триместрі вагітності. У зв’язку зі значним зростанням тироксин-зв’язуючих глобулінів рівні загального тироксину та трийодтироніну суттєво підвищуються з перших тижнів вагітності і можуть збільшуватися у 1,5 раза. Концентрація вільних трийодтироніну і тироксину знижується у другій половині вагітності, під час пологів вона в середньому на 10–15% нижча, ніж у загальній популяції. Часто при вагітності визначаються позитивні рівні антитіл до тиреопероксидази і тиреоглобуліну. Згідно з міжнародними клінічними стандартами не рекомендується здійснювати тотальний скринінг рівня тиреоїдних гормонів у I триместрі вагітності. Визначення тиреотропного гормону проводять лише у групах ризику наявності патології щитоподібної залози. В Україні визначення рівня цього гормону може бути рекомендоване кожній вагітній у I триместрі вагітності або на момент першого звернення. Гіпотиреоз виникає приблизно у 0,5% вагітних, а основною його причиною є аутоімунний тиреоїдит. Препаратом вибору для лікування гіпотиреозу є левотироксин. Інші препарати не мають підґрунтя для використання. Найпоширенішою причиною аутоімунного гіпертиреозу є дифузний токсичний зоб, що виникає у 0,1–1% усіх вагітностей, а серед неаутоімунних причин перше місце посідає гестаційний гіпертиреоз (1–3%). Вважається, що субклінічний гіпертиреоз будь-якого походження не потребує лікування упродовж усієї вагітності. Лікування селеном не рекомендоване жодними клінічними настановами, навіть у жінок із позитивними антитиреоїдними антитілами. Доброякісні вузли щитоподібної залози не потребують лікування впродовж вагітності, а у випадках диференційованого раку щитоподібної залози можна застосовувати помірну супресивну терапію препаратами тироксину.

Management of chronic myeloid leukemia during pregnancy: a retrospective analysis at a single center

We analyzed the management and outcomes of pregnancies of patients with chronic myeloid leukemia at a single center over fifteen years. Among the 203 CML female patients, there were ten pregnancies in seven women, all of them not planned. In three cases, the chronic myeloid leukemia diagnosis was made during pregnancy. Five patients received tyrosine kinase inhibitors in the first weeks of pregnancy and the drug was interrupted until delivery. One patient lost complete cytogenetic response, and two patients lost the hematological response. A patient with a stable major molecular response had two successful pregnancies without loss of response. There were four premature births. There were no maternal adverse events, fetal malformation or death. All patients received Interferon-alpha during gestation, and two received hydroxyurea for a short period. Leukapheresis was performed in two patients for hyperleukocytosis control. One patient with sickle cell disease died from disease progression six months after delivery. ConclusionsThe tyrosine kinase inhibitors ministration should be interrupted during pregnancy. Patients should be advised to achieve a stable and deep molecular response if they plan to conceive, to avoid the risk of disease progression.

A case of holoprosencephaly and a little review

Holoprosencephaly (HPE) is a birth defect that occurs during the first weeks of pregnancy and as a result the prosencephalon does not clearly divide in diencephalon, two halves of the telencephalon and lateral ventricles in the brain of the fetus and, in general, HPE is accompanied by facial defects. There are three main types of holoprosencephaly according to severity; alobar, semi-lobar and lobar. We report here a case that could be defined as a semi-lobar form of HPE with hydrocephalus and scarce facial malformations.

Noninvasive prenatal diagnosis by cell-free DNA screening for fetomaternal HPA-1a platelet incompatibility.

The development of new noninvasive approaches for the diagnosis of human platelet antigen (HPA)-1 fetomaternal incompatibility has become of great interest. These approaches allow determination of whether the fetus is incompatible or not with the mother and a decision on antenatal therapy to avoid fetal or neonatal alloimmune thrombocytopenia (FNAIT). The objective of this work was to perform rapid, noninvasive prenatal test for HPA-1ab fetal antigen detection after the detection of an HPA-1-homozygous mother by using plasma cell-free DNA (cfDNA). The HPA-1 genotypes of 142 pregnant women and 17 nonpregnant controls were retrospectively determined by high-resolution melting (HRM) polymerase chain reaction (PCR). Coamplification at lower denaturation temperature (COLD) HRM PCR was performed to determine the fetal genotype analyzing cfDNA from all HPA-1bb pregnant women. After the HRM analysis, the following genotypes were identified: HPA-1aa (71.13%), HPA-1bb (2.8%), and HPA-1ab (26.06%). Four HPA-1bb-homozygous pregnant women were carrying an incompatible fetus. Plasma samples from these mothers were analyzed by HRM COLD-PCR. Homozygous HPA-1bb pregnant women carrying an HPA-1ab-heterozygous fetus did not group with either the HPA-1ab or the HPA-1bb controls. Thus, COLD-PCR analysis allows the detection of HPA-1ab-heterozygous fetuses carried by homozygous mothers during first weeks of pregnancy. The fetal genotype from HPA-1bb-homozygous women was detected by a noninvasive prenatal test as soon as 12 weeks of gestation.

Роль найдавнішого еволюційного механізму під час вагітності

The article deals with the role of acid-base balance as the most evolutionarily long-standing mechanism of homeostasis regulation and its features by pregnancy. The objective: to determine the features of acid-base balance in pregnant women with vomiting in first trimester. Materials and methods. 109 pregnant women in the first and second trimester were examined, they were divided into 2 groups – 58 pregnant women in the first trimester had vomiting with different degrees of severity, and 51 pregnant women in group II had no complains in first trimester. In all subjects twice, in terms of 10–11 and 20–21 weeks, the hydrogen index, the concentration of carbonate-ion and the partial pressure of CO2 in the plasma were determined. Results. It is proved by biochemical calculations, that the statistically unlikely shift of Ph to the alkaline reaction observed with the progression of pregnancy is based on a significant difference in the absolute concentration of hydrogen ions. These changes are necessary for the adequate transport of ions through the membranes of the developing placental system. Despite the loss of electrolytes in women with early gestosis, these changes do not go beyond the limits of physiological. Conclusion. 1. Pregnant patients with vomiting during first weeks of pregnancy, despite the loss of fluid and electrolytes, maintain the stability of the acid-base balance with a slight tendency to alkalosis. 2. Pregnant women without first trimester complains do not have described moderate plasma alkalisation, whose physiological role requires further observation and research. Key words: concentration of hydrogen ions, alkalosis, vomiting in first pregnancy trimester.

Effects of maternal folic acid supplementation on airway remodeling and allergic airway disease development

Objective: Maternal folic acid supplementation has been recommended prior to and during the first trimester of pregnancy to reduce the risk of infant neural tube defects. However, an uncertain relationship between folic acid supplementation during pregnancy and development of childhood asthma exists. Recent data show a methyl donor-rich diet could increase the risk of developing allergic airway disease through DNA methylation and aberrant gene transcription. This study evaluated the effect of folic acid supplementation during pregnancy on airway remodeling and allergic airway disease vulnerability in a mouse asthma model.Methods: BALB/c mice were divided into four groups according to gestational folic acid supplementation and postnatal ovalbumin (OVA) exposure: Group 1 (whole pregnancy folic acid supplementation + OVA-exposed group), Group 2 (first gestational week folic acid supplementation + OVA-exposed group), Group 3 (no folic acid supplementation + OVA-exposed group), and Group 4 (control group). Offspring were sacrificed on day 45 for immunohistological and ultrastructural tests.Results: In OVA challenged groups, folic acid supplementation led to a thicker epithelial and subepithelial smooth muscle layer than in the unsupplemented group. Moreover, folic acid supplementation during whole pregnancy (Group 1) was associated with a thicker epithelial and subepithelial smooth muscle layer than folic acid supplementation during the first week of pregnancy (Group 2), suggesting a duration–response relationship. Electron microscopic imaging revealed that structural changes including the loss of epithelial integrity, thickening of basement membrane, and subepithelial fibrosis were more prominent in the folic acid supplementation groups.Conclusions: This study suggested that maternal folic acid supplementation during pregnancy affects airway remodeling and increases the allergic responses induced by ovalbumin challenge in offspring. In addition, the effect size increased as the duration and cumulative dose increased.

Understanding vitamin D metabolism in pregnancy: From physiology to pathophysiology and clinical outcomes

This critical time frame of intrauterine life development is considered of major importance on the metabolic imprinting of overall health of the offspring, in later life. This requires a delicate immune balance that nurtures the allogeneic fetus, while maintaining reactivity against pathogens. Dysregulation of these tightly controlled biophenomena at a systemic and placental level, have been considered as a potential mechanism mediating pathogenesis of preeclampsia and spontaneous birth. In this context, vitamin D has been considered as a significant regulator of both innate and adaptive immunity by regulating cell proliferation, differentiation and apoptosis.Vitamin D metabolism during pregnancy manifests striking differences as compared to the non-pregnant state. Calcitriol is increasing >2–3 fold in the first weeks of pregnancy whereas maternal 25-hydroxyvitamin D crosses the placental barrier and represents the main pool of vitamin D in the fetus. Moreover, during pregnancy, vitamin D receptor and regulatory metabolic enzymes are expressed in the placenta and decidua, indicating a potential critical point in the immunomodulation at the maternal-fetal interface. Considering these effects, maternal hypovitaminosis D during pregnancy has been associated with pregnancy related disorders. This review focuses on the mechanistic basis of these adaptive changes, as a background for the development of pregnancy related disorders, with a discourse on the pathophysiology relating hypovitaminosis D and clinical outcomes.

Value change in men and women entering parenthood: New mothers' value priorities shift towards Conservation values

There is little research on how life transitions influence value priorities. Our purpose was to investigate, within the framework provided by Schwartz's Values Theory, the effects of entering parenthood on personal values. Study 1 (N=12,850), employing cross-sectional European Social Survey data, showed that Finnish mothers, as compared to non-mothers, were closer to the Conservation pole of the value dimensions that opposes Conservation values with Openness to Change values. Study 2 longitudinally followed Finnish couples (N=292) entering parenthood from the first weeks of pregnancy to three months after childbirth. Both self- and spouse-ratings of values showed that new mothers' value priorities shifted towards Conservation values. New mothers perceived a similar shift in new fathers' personal values, but no changes occurred in men's self-ratings. Neither study suggested change on the value dimension that opposes Self-Transcendence values with Self-Enhancement values. Across the cross-sectional and longitudinal designs, and across self- and spouse-ratings of values, our results consistently suggest that new mothers' shift their value priorities in the direction of increased Conservation over Openness to Change. These results are consistent with the notion that value change may facilitate adaptation to life events.

Signs of embryo-maternal communication: miRNAs in the maternal serum of pregnant pigs.

Circulating miRNAs were proposed to be indicators of normal or complicated pregnancies. Based on this knowledge and our recent transcriptomic approach showing expression of miRNAs in the porcine endometrium, conceptuses and uterine extracellular vesicles during pregnancy, we have hypothesized that signs of ongoing local embryo-maternal crosstalk involving miRNAs can be detected in the circulation of pregnant gilts as early as a few days after maternal recognition of pregnancy. By applying several molecular biology techniques that differ in dynamic range and precision in maternal serum of Day 16 pregnant pigs, we were able to show for the first time increased levels of several miRNAs, previously reported to be expressed in either conceptuses and extracellular vesicles (miR-26a and miR-125b) or pregnant endometrium (miR-23b). Our results clearly showed that real-time RT-PCR and digital PCR are the most reliable methods, being able to detect small-fold changes of low-abundant circulating miRNAs. Further validation in a separate group of gilts confirmed an increase in miR-23b and miR-125b levels. In silico analyses identified pregnancy-related biological processes and pathways affected by these miRNAs. Target prediction analysis revealed hundreds of porcine transcripts with conserved sites for these miRNAs, which were classified into signaling pathways relevant to pregnancy. We conclude that a unique set of miRNAs can already be observed in the circulation of pigs during the first weeks of pregnancy, as a result of the initiation of embryo-maternal communication.

Hot Days in Early Pregnancy: A Potential Risk Factor for Congenital Heart Defects

Hot Days in Early Pregnancy: A Potential Risk Factor for Congenital Heart Defects

Efficacy of mifepristone and misoprostol in termination of pregnancy in second and third trimester versus intraamniotic application of prostaglandins

Introduction: According to the published data, a combination of mifepristone and misoprostol is recommended in literature for labour induction in the second and third pregnancy trimester after a foeticide due to a fetal malformation or intrauterine fetal death and for abortion induction in the first pregnancy weeks. At our department we perform foeticide by applying Fentanyl and Xylocaine into the fetal heart. Since the intraamnial input is applied in this procedure, we also perform labour induction by intraamnial prostaglandin application. During the first weeks of pregnancy we performs abortion induction with mifepristone and misoprostol. Through the analysis of our own data, we aimed at establishing in what time fetal expulsion occurs after abortion induction with mifepristone and misoprostol compared to labour induction through intraamnial prostaglandin application. Methods: The retrospective study included all women on whom abortion or labour induction was performed between 2010 and 2015 due to fetal malformations established by means of ultrasound. The first group included all participants in the 16th–24th week of pregnancy or with the fetus weight under 500 g determined through ultrasound where the abortion induction was performed with mifepristone and misoprostol according to the following protocol: mifepristone 200 mg orally, followed 36–48 h later by misoprostol 800 μg vaginally, then misoprostol 400 μm orally, 3-hourly, to a maximum of four further doses. The second group included women after the 24th week of pregnancy or with the fetus weight above 500 g determined through ultrasound. Labour induction were performed through intraamnial 1000 μg prostaglandin application. We compared the time at which the fetal expulsion occurred after the beginning of induction in the first group with the same time in the second group. Results and conclusions: Based on the data from literature, the best abortion or labour induction method is the application of mifepristone and misoprostol regardless of the duration of pregnancy. The aim of our research was to establish whether the cases when a foeticide needs to be performed and therefore intraamnial input is already being used it also makes sense to apply prostaglandins in order to commence induction at the same time. Compared to the protocol with mifepristone and misoprostol we benefit from extra time since it is recommended to wait 36–48 h after mifepristone application before misoprostol application is continued. Based on the data from literature, the time to fetal expulsion in case of induced abortions or labours is proportional to the duration of pregnancy. With our research, we aimed to prove that in the group with the labour induction by means of intraamnial prostaglandin application despite being further into the pregnancy, the time to fetal expulsion is shorter due to the 36–48-h-long break in the mifepristone and misoprostol protocol.

Vasoactive Intestinal Peptide modulates trophoblast-derived cell line function and interaction with phagocytic cells through autocrine pathways.

Trophoblast cells migrate and invade the decidual stroma in a tightly regulated process to maintain immune homeostasis at the maternal-placental interface during the first weeks of pregnancy. Locally synthesized factors modulate trophoblast cell function and their interaction with maternal leukocytes to promote the silent clearance of apoptotic cells. The vasoactive intestinal peptide (VIP) is a pleiotropic polypeptide with trophic and anti-inflammatory effects in murine pregnancy models. We explored the effect of VIP on two human first trimester trophoblast cell lines, particularly on their migration, invasiveness and interaction with phagocytic cells, and the signalling and regulatory pathways involved. We found that VIP enhanced trophoblast cell migration and invasion through the activation of high affinity VPAC receptors and PKA-CRE signalling pathways. VIP knocked-down trophoblast cells showed reduced migration in basal and leukemic inhibitor factor (LIF)-elicited conditions. In parallel, VIP-silenced trophoblast cells failed to induce the phagocytosis of apoptotic bodies and the expression of immunosuppressant markers by human monocytes. Our results suggest that VIP-mediated autocrine pathways regulate trophoblast cell function and contribute to immune homeostasis maintenance at placentation and may provide new clues for therapeutic intervention in pregnancies complicated by defective deep placentation.

Prolactinoma and pregnancy: From the wish of conception to lactation

Prolactinoma is a common cause of infertility in young women and treatment with dopamine agonists (DA) allows restoration of fertility in over 90% of the cases. Both bromocriptine and cabergoline have shown a good safety profile when administered during early pregnancy. In particular, data on exposure of the fetus or embryo to cabergoline during the first weeks of pregnancy have now been reported in more than 900 cases, and do indicate that cabergoline is safe in this context. There is no increase in the frequency of spontaneous miscarriage, premature delivery, multiple births or neonatal malformations, and follow-up studies of the children for up to 12years after fetal exposure to cabergoline did not show any physical or developmental abnormalities. These women should therefore continue DA treatment until pregnancy has been initiated. Treatment discontinuation is recommended at that time in women with microprolactinoma or non-compressive macroprolactinoma. For microprolactinomas, the risk of symptomatic tumour enlargement during pregnancy is very low (2–3%). It is higher for macroprolactinomas (20–30%) and careful follow-up is advised, including MRI without contrast injection if symptoms or visual disturbances develop. If a symptomatic tumour enlargement does occur, reinitiation of the dopamine agonist (BRC or CAB) is indicated rather than surgery. Breast-feeding has no harmful effect on tumour growth and DA treatment, if still needed, may be postponed as long as breast-feeding is desired. Finally, about 40% of women with a microprolactinoma or an intermediate size macroprolactinoma may be in prolonged remission after one or more pregnancies.

El estrés materno como factor de riesgo para fisuras labio-palatinas

Introduction: several studies have shown an association between stress caused by natural disasters, acts of terrorism and war, which have been corroborated by experimental studies in rats, with presence of oral clefts (FO) in the children of women who suffered stress in the first weeks of pregnancy. Objectives: To demonstrate the relationship between stress caused by the earthquake and tsunami that struck the central and south regions of Chile, on February 27, 2010 and the prevalence rate of FO in the disaster area. Material and Methods: Registration of ECLAMC (Latin American Collaborative Study of Congenital Malformations) Period 2000- 2011. With this information we created two groups: Group 1: Children born before the event, from 2002 to 2009 up to 6 months after earthquake, that means August 2010. Group 2: the postearthquake period, from the seventh month after the earthquake (September) until the end of 2011. Results: the prevalence of oral clefts of the first group was 0.88 per thousand births (0.57 for cleft lip and cleft palate 0.30) .and the second group of 1.07 per thousand, (0.70 cleft lip and cleft palate 0.37) statistically significant difference (p

Antidepressant Prescription Claims Among Reproductive-Aged Women With Private Employer-Sponsored Insurance - United States 2008-2013.

Antidepressant medication use during pregnancy has been increasing in the United States (1). Many women require antidepressants on an ongoing basis, and a clear consensus on the safest medication options for both the mother and her fetus does not exist (2). Given that half of all U.S. pregnancies are unplanned (3), antidepressant use will occur during the first weeks of pregnancy, a critical period for fetal development. To understand trends among women of reproductive age, CDC used Truven Health's MarketScan Commercial Claims and Encounters data* to estimate the number of antidepressant prescriptions filled by women aged 15-44 years with private employer-sponsored insurance. During 2008-2013, an average of 15.4% of women aged 15-44 years filled at least one prescription for an antidepressant in a single year. The most frequently filled antidepressants included sertraline, bupropion, and citalopram. Prescribing of antidepressants is common, and research on antidepressant safety during pregnancy needs to be accelerated to provide evidence-based information to health care providers and women about the potential risks for antidepressant exposure before and during pregnancy and between pregnancies.

What is the placenta?

Discarded at birth, the placenta is a highly complex and fascinating organ. During the course of a pregnancy, it acts as the lungs, gut, kidneys, and liver of the fetus. The placenta also has major endocrine actions that modulate maternal physiology and metabolism and provides a safe and protective milieu in which the fetus can develop. The human placenta undergoes dramatic transformations in form and function between the first trimester, when organogenesis occurs, and the remainder of pregnancy that reflect evolutionary responses to changing oxygen concentrations in the earth's atmosphere. Recent research indicates a more interactive dialogue between the placenta and the maternal tissues than previously recognized. The endometrial glands provide histotrophic support during the first weeks of pregnancy, and the placenta appears able to stimulate its own development by up-regulating gland activity in response to endocrine signals. Extravillous trophoblast cells migrate from the placenta into the uterine wall, in which they interact with cells of the maternal innate immune system. These interactions have a physiological, rather than a classical immunological, outcome and most probably mediate remodeling of the uterine spiral arteries that supply the placenta. Furthermore, deportation of aggregates of transcriptionally active trophoblast nuclei, and the release of exosomes carrying microribonucleic acids challenge our perceptions of fetal-maternal signaling and where the placental interface actually lies. Here we reconsider definitions of the placenta in the light of these recent advances.