Immune checkpoint inhibitor administration during pregnancy: a case series

A minority of women of childbearing potential are tested for pregnancy before chemoimmunotherapy: an Australian cancer centre experience

BACKGROUND

Chemotherapy is potentially harmful to a developing foetus, and there are limited data on the foetal impact of chemoimmunotherapy (CIT). Therefore, determining pregnancy status prior to initiation of CIT should be standard of care.

AIMS

To determine how many women of childbearing age are tested for pregnancy prior to immunochemotherapy administration.

METHODS

A retrospective chart review at a large Australian metropolitan cancer referral centre, including 304 women aged 18-51 years with a diagnosis of cancer receiving outpatient-based CIT between 1 May 2015 and 12 June 2020. We assessed the uptake of pregnancy screening and contraception counselling prior to and during first-line CIT.

RESULTS

Only 17.3% of CIT cycles (n = 416) screened patients for pregnancy no more than 90 days prior to administration, and the median time between pregnancy screening and treatment was approximately 3 weeks. One patient with early breast cancer had a spontaneous miscarriage estimated at 3-4 weeks' gestation, and neither the patient nor the treating oncologist was aware of this event. This was also the only patient who had a pregnancy test beyond the first cycle of CIT during their treatment.

CONCLUSIONS

Our results highlight a concerningly low rate of pregnancy screening in women of childbearing age receiving CIT. The implication of missing a positive pregnancy test in this group of women could result in foetal complications, accidental miscarriage, potential bleeding risks and avoidable psychosocial stress. This highlights the urgent need for guidelines to mandate pregnancy testing in women of childbearing age receiving CIT and evidence-based implementation tools.

Breast cancer during pregnancy-The oncologist's point of view

Breast cancer is the most common malignancy diagnosed during or directly after pregnancy. Differences in pathogenesis and prognosis identify two distinct patient groups, those with breast cancer during pregnancy and those with postpartum breast cancer which, for reasons not completely understood, is associated with worse outcomes. Compared with breast cancer in the non-pregnant patient, several limitations in terms of both local and systemic therapy are applied to limit fetal harm. Treatment is nevertheless delivered with curative intent, therefore avoiding harmful delays in therapy initiation, unnecessary therapy de-escalation or chemotherapy dose modifications is strongly recommended. In this short commentary, we briefly review current evidence and treatment guidelines and provide recommendations for optimal oncologic management of pregnancy-related breast cancer.

Immune Checkpoint Inhibitor Use During Pregnancy and Outcomes in Pregnant Individuals and Newborns

Importance

With the widespread use of immune checkpoint inhibitors (ICIs), concerns about their pregnancy outcomes through maternal exposure have emerged, and clinical comparative data are lacking.

Objective

To assess the risk of pregnancy-, fetal-, and/or newborn-related adverse outcomes associated with exposure to ICIs compared with exposure to other anticancer agents.

Design, Setting, and Participants

In this cohort study, all reports mentioning a pregnancy-related condition and an antineoplastic agent (Anatomical Therapeutic Chemical classification group L01) used for a cancer indication registered in the World Health Organization international pharmacovigilance database VigiBase up to June 26, 2022, were extracted.

Exposure

Anticancer agents, including ICIs, used during pregnancy for a cancer indication. Immune checkpoint inhibitors included blockers of programmed cell death 1 (PD1) or its ligand (PD-L1) or cytotoxic T-lymphocyte-associated protein 4 (CTLA4).

Main Outcomes and Measures

The main outcome was the reporting odds ratio (ROR) for maternal, fetal, or newborn complications in patients treated with ICIs vs any other anticancer drug. Adverse events, categorized into 45 individual maternofetal adverse outcomes, were directly mapped to Medical Dictionary for Regulatory Activities preferred terms in VigiBase.

Results

A total of 3558 reports (ICI: 91 [2.6%]; other anticancer drugs: 3467 [97.4%]) were included in the analysis. In the ICI group, most reports were from the US (60 [65.9%]), and the mean (SD) patient age was 28.9 (10.2) years; in 24 of 55 reports with data on cancer type (43.6%), patients were treated for melanoma. The molecules involved in the ICI group were anti-PD1 (58 reports [63.7%]), anti-PD1 plus anti-CTLA4 (15 [16.5%]), anti-CTLA4 (13 [14.3%]), anti-PD-L1 (4 [4.4%]), and anti-PD1 plus anti-lymphocyte activation gene 3 (1 [1.1%]). An ICI was used in combination with a non-ICI anticancer agent in 10 participants (11.0%). Compared with other anticancer drugs, none of the 45 adverse outcomes identified were overreported in the group exposed to ICIs. However, preterm birth was significantly overreported for the anti-PD1 plus anti-CTLA4 combination compared with other anticancer drugs (12 of 15 [80.0%] vs 793 of 3452 [23.0%]; ROR, 13.87; 95% CI, 3.90-49.28; P < .001) but not for anti-PD-L1 or anti-CTLA4 monotherapy. Three reports of possibly immune-related maternofetal events were identified: 1 case of maternal antiphospholipid syndrome leading to spontaneous abortion, 1 case of pneumonitis leading to neonatal respiratory distress syndrome and death, and 1 case of transient congenital hypothyroidism.

Conclusions and Relevance

In this cohort study of 91 individuals exposed to ICIs during pregnancy, ICI exposure was not associated with overreporting of specific adverse pregnancy, fetal, and/or newborn outcomes compared with other anticancer treatments. However, due to possible rare immune-related neonatal adverse events, ICI use in pregnant women should be avoided when possible, especially the anti-PD1 plus anti-CTLA4 combination.

Pregnancy and delivery in an advanced cancer survivor with immune checkpoint inhibitor-induced type 1 diabetes: a case report

PURPOSE

Given the rarity and elderly onset of immune checkpoint inhibitor (ICI)-induced type 1 diabetes (ICI-T1DM), cases leading to delivery are rare.

METHOD

To our knowledge, this is the first case report of childbirth in a patient with ICI-T1DM after cancer survival. A 32-year-old woman was started on Nivolumab for metastatic parotid cancers one year after total parotidectomy.

RESULT

The patient developed ICI-T1DM after 43 cycles and started multiple daily insulin therapy and self-monitoring of blood glucose. Complete response was maintained for 2 years by nivolumab, and she finished nivolumab in 77 cycles to attempt pregnancy. During the follow-up period, she began using a sensor-augmented pump (SAP). She had undetectable serum and urinary C-peptide when she started SAP. Her HbA1c level decreased from 7.8 to 6.6% without increasing hypoglycemia in one year. The patient remained in complete response after ICI discontinuation, and embryo transfer was initiated. Pregnancy was confirmed after a second embryo transfer (21 months after ICI discontinuation). At 36 weeks and 6 days, an emergency cesarean section was performed due to the onset of preeclampsia. The baby had hypospadias and bifid scrotum but no other complications or neonatal intensive care unit admission.

CONCLUSION

Because ICI discontinuation and ICI-T1DM carry risks for the patient and child, the decision regarding pregnancy warrants careful consideration. Diabetologists should collaborate with patients and other clinical departments to develop a treatment plan for childbirth.

ESMO Expert Consensus Statements on the management of breast cancer during pregnancy (PrBC)

The management of breast cancer during pregnancy (PrBC) is a relatively rare indication and an area where no or little evidence is available since randomized controlled trials cannot be conducted. In general, advances related to breast cancer (BC) treatment outside pregnancy cannot always be translated to PrBC, because both the interests of the mother and of the unborn should be considered. Evidence remains limited and/or conflicting in some specific areas where the optimal approach remains controversial. In 2022, the European Society for Medical Oncology (ESMO) held a virtual consensus-building process on this topic to gain insights from a multidisciplinary group of experts and develop statements on controversial topics that cannot be adequately addressed in the current evidence-based ESMO Clinical Practice Guideline. The aim of this consensus-building process was to discuss controversial issues relating to the management of patients with PrBC. The virtual meeting included a multidisciplinary panel of 24 leading experts from 13 countries and was chaired by S. Loibl and F. Amant. All experts were allocated to one of four different working groups. Each working group covered a specific subject area with two chairs appointed: Planning, preparation and execution of the consensus process was conducted according to the ESMO standard operating procedures.

Society for Immunotherapy of Cancer (SITC) clinical practice guideline on immunotherapy for the treatment of melanoma, version 3.0

Since the first approval for immune checkpoint inhibitors (ICIs) for the treatment of cutaneous melanoma more than a decade ago, immunotherapy has completely transformed the treatment landscape of this chemotherapy-resistant disease. Combination regimens including ICIs directed against programmed cell death protein 1 (PD-1) with anti-cytotoxic T lymphocyte antigen-4 (CTLA-4) agents or, more recently, anti-lymphocyte-activation gene 3 (LAG-3) agents, have gained regulatory approvals for the treatment of metastatic cutaneous melanoma, with long-term follow-up data suggesting the possibility of cure for some patients with advanced disease. In the resectable setting, adjuvant ICIs prolong recurrence-free survival, and neoadjuvant strategies are an active area of investigation. Other immunotherapy strategies, such as oncolytic virotherapy for injectable cutaneous melanoma and bispecific T-cell engager therapy for HLA-A*02:01 genotype-positive uveal melanoma, are also available to patients. Despite the remarkable efficacy of these regimens for many patients with cutaneous melanoma, traditional immunotherapy biomarkers (ie, programmed death-ligand 1 expression, tumor mutational burden, T-cell infiltrate and/or microsatellite stability) have failed to reliably predict response. Furthermore, ICIs are associated with unique toxicity profiles, particularly for the highly active combination of anti-PD-1 plus anti-CTLA-4 agents. The Society for Immunotherapy of Cancer (SITC) convened a panel of experts to develop this clinical practice guideline on immunotherapy for the treatment of melanoma, including rare subtypes of the disease (eg, uveal, mucosal), with the goal of improving patient care by providing guidance to the oncology community. Drawing from published data and clinical experience, the Expert Panel developed evidence- and consensus-based recommendations for healthcare professionals using immunotherapy to treat melanoma, with topics including therapy selection in the advanced and perioperative settings, intratumoral immunotherapy, when to use immunotherapy for patients with BRAFV600-mutated disease, management of patients with brain metastases, evaluation of treatment response, special patient populations, patient education, quality of life, and survivorship, among others.

A Review on Inflammasomes and Immune Checkpoints in Pre-Eclampsia Complicated with Tuberculosis and Human Immune Deficiency Virus

The current review evaluates how inflammasomes and immune checkpoints are regulated in pre-eclampsia (PE) associated with tuberculosis (TB) and Human Immune Deficiency Virus (HIV). Studies indicate that inflammasomes such as (NRLP3, NEK7, and AIM2) and immune checkpoints such as (CLT4, PD-1, TIM3, and LAG-3) are dysregulated in TB- and HIV-infected individuals, and also in pre-eclamptic pregnancies, which explains why pregnant women who are either infected with TB or HIV have an increased risk of developing PE. Evidence suggests that inhibition of inflammasomes and immune checkpoints may assist in the development of novel anti-inflammatory drugs for the prevention and management of PE in patients with or without TB and HIV infection.

Pregnancy-associated Cancer and Chemotherapy during Pregnancy

The diagnosis of pregnancy-associated cancer, although rare, is a condition of great human and social significance and difficult clinical management. A pregnancy-associated neoplasm is defined as a cancer diagnosis made during pregnancy or within 12 months after delivery/abortion. The most common cancers in pregnancy occur most frequently in women of reproductive age with an incidence overall like that observed in non-pregnant women of the same age. This incidence is likely to increase in view of both the expected increase in certain malignancies among young women (particularly breast cancer and melanoma) and the increasing frequency of pregnancies undertaken later in life (fourth and fifth decades of life) that is characterizing modern society. Chemotherapy is generally contraindicated before 12 weeks of pregnancy due to the increased risk of congenital anomalies while exposure in the second and third trimester of pregnancy to chemotherapy has been associated with more growth restriction and preterm delivery. Clinical decisions about the optimal management should consider maternal and fetal characteristics with the involvement of a multidisciplinary team.

Immunochemotherapy for life-threatening haematological malignancies in pregnancy: a systematic review of the literature and cross-sectional analysis of clinical trial eligibility

The management of potentially life-threatening malignancies in pregnancy is complicated by a lack of robust safety and efficacy evidence. This data shortage stems from a historical exclusion of women of childbearing potential from prospective clinical trials due to concerns around potential teratogenicity and toxicity of investigational agents. We conducted a systematic review of published data on immunochemotherapeutic treatment of life-threatening haematological malignancies in pregnancy between 2010 and 2022, and the maternal and neonatal outcomes. We then performed a cross-sectional observational study of clinical trial protocols on ClinicalTrials.gov, between 2016 and 2022, recruiting women of childbearing potential with potentially life-threatening haematological malignancies, collecting trial demographic data, and documenting whether pregnant or lactating women were explicitly excluded, along with the type and duration of contraception required for women of childbearing potential. We included 17 studies for analysis in our systematic review. A total of 595 women were treated with immunochemotherapy during pregnancy, with a median age of 29 years (range 14-48). Of these, 81 women (14%) were treated in the first trimester, and 514 (86%) were treated in the second and third trimesters collectively. In total, 68 trials for acute myeloid leukaemia, acute lymphocytic leukaemia, high-grade non-Hodgkin lymphoma, and Hodgkin lymphoma (40%, 26%, 21%, and 13%, respectively) were included in our ClinicalTrials.gov analysis. Most protocols (66 [97%]) explicitly excluded pregnant women, with 40 (69%) not providing a rationale for exclusion. The potential harm to the fetus from anti-cancer therapy has historically been given greater moral precedence than a pregnant woman's autonomy. This pattern is reflected in the lack of rigorous evidence for immunochemotherapy in pregnancy and a universal exclusion of pregnant and lactating women from clinical trial protocols in this study. Nonetheless, the administration of systemic chemotherapy in the second and third trimesters was not associated with an increased rate of congenital malformations or perinatal mortality in our systematic review cohort, with maternal outcomes broadly comparable to those of the non-pregnant population.

Society for Immunotherapy of Cancer (SITC) clinical practice guideline on immunotherapy for the treatment of gynecologic cancer

Advanced gynecologic cancers have historically lacked effective treatment options. Recently, immune checkpoint inhibitors (ICIs) have been approved by the US Food and Drug Administration for the treatment of cervical cancer and endometrial cancer, offering durable responses for some patients. In addition, many immunotherapy strategies are under investigation for the treatment of earlier stages of disease or in other gynecologic cancers, such as ovarian cancer and rare gynecologic tumors. While the integration of ICIs into the standard of care has improved outcomes for patients, their use requires a nuanced understanding of biomarker testing, treatment selection, patient selection, response evaluation and surveillance, and patient quality of life considerations, among other topics. To address this need for guidance, the Society for Immunotherapy of Cancer (SITC) convened a multidisciplinary panel of experts to develop a clinical practice guideline. The Expert Panel drew on the published literature as well as their own clinical experience to develop evidence- and consensus-based recommendations to provide guidance to cancer care professionals treating patients with gynecologic cancer.

Primary Mucosal Melanoma of the Lip With GNA11 Mutation in a 23-Year-Old Pregnant Woman

Mucosal melanoma represents a small proportion of all melanoma cases and is associated with a worse prognosis. Primary malignant melanoma of the lip (PMML) is far less common, and only a few cases have been reported since 1997, most commonly in China, Japan, Uganda, and India. Most of these cases have been associated with the gene C-KIT. As a result, treatment guidelines surrounding mucosal melanoma are unclear, especially in complicated populations such as pregnant women. Mutations in theGNAQ and GNA11 genes have been found to be associated with uveal melanoma, while they are rarely associated with mucosal melanoma. We present the case of a 23-year-old pregnant woman who was found to have likely primary malignant melanoma of the lip that metastasized to the left jaw, neck, breast, lungs, and ovaries and was found to be positive for both the BRAF-MLL3 and GNA11 mutation.

Dominant immune cells in pregnancy and pregnancy complications: T helper cells (TH1/TH2, TH17/Treg cells), NK cells, MDSCs, and the immune checkpoints

Pregnancy problems including recurrent pregnancy loss, repeated implantation failure and pre-eclampsia  are common problems in the reproductive ages. Different reasons such as genetic, immunological, and environmental agents and also infections could develop these complications. In those cases in which the cause of the abortion is diagnosed, the chance of a successful pregnancy is increased by eliminating defective factors. However, in patients with unknown causes, there may be an imbalance in immune cells pattern. As a matter of fact, an inappropriate immune response is often associated with a failed pregnancy. Hence, the focus of treatment is to increase tolerance, not to suppress maternal immune system. These findings are linked to an elevated number of Treg cells and immune checkpoints through normal pregnancy. The present review discusses the balance of myeloid-derived suppressor cells, natural killer cells, T cells, and immune checkpoints, and also targeting them to maintain pregnancy and prevent associated complications.

Immune Checkpoint Inhibitors and Pregnancy: Analysis of the VigiBase® Spontaneous Reporting System

In pregnancy, immune checkpoint pathways are involved in the maintenance of fetomaternal immune tolerance. Preclinical studies have shown that immune checkpoint inhibitors (ICIs) increase the risk of fetal death. Despite the fact that using ICIs in pregnant women and women of childbearing potential is not recommended, some case reports of ICI exposure in pregnancy have been published showing favorable fetal outcomes. This study aimed to gain further insight into ICI safety in pregnancy by querying VigiBase^®, the World Health Organization's spontaneous reporting system. We performed raw and subgroup disproportionality analyses using the reporting odds ratio and comparing ICIs with the entire database, other antineoplastic agents, and other antineoplastic agents gathered in VigiBase^® since 2011. Across 103 safety reports referring to ICI exposure during the peri-pregnancy period, 56 reported pregnancy-related outcomes, of which 46 were without concomitant drugs as potential confounding factors. No signals of disproportionate reporting were found for spontaneous abortion, fetal growth restriction, and prematurity. In light of the expanding indications of ICIs, continuous surveillance by clinicians and pharmacovigilance experts is warranted, along with pharmacoepidemiological studies on other sources of real-world evidence, such as birth records, to precisely assess ICI exposure during the peri-pregnancy period and further characterize relevant outcomes.

Rapid progression of hepatocellular carcinoma in a pregnant woman: A case report

Hepatocellular carcinoma (HCC) in pregnant women is rare; however, a recurrence of the disease is followed by rapid lesion progression during pregnancy. We experienced a case in which HCC recurred during pregnancy and rapidly worsened. After delivery at 33 weeks, she underwent chemotherapy and made a good progress.

Case report: Reproductive organ preservation and subsequent pregnancy for an infertility patient with lynch syndrome-associated synchronous endometrial cancer and colon cancer after treatment with a PD-1 checkpoint inhibitor

Currently, immune checkpoint inhibitors (ICIs) are the mainstay of treatment for Lynch syndrome patients. However, the tumor regression features in radiology and pathology are inconsistent for patients who are treated with ICIs, which sometimes confuses surgical decision-making. Here, we report a case in which a 36-year-old patient suffering from infertility was diagnosed with Lynch syndrome-associated synchronous endometrial cancer and colon cancer, and persistently enlarged left iliac paravascular lymph nodes were detected after receiving sintilimab treatment, a programmed cell death 1 (PD-1) receptor inhibitor. Fortunately, when she was about to undergo hysterectomy and bilateral salpingo-oophorectomy, intraoperative pathology examination did not reveal any cancer cells in these lymph nodes, and therefore, her reproductive organs were preserved. Later, the patient successfully conceived and gave birth to a healthy male neonate with no immune-related adverse events (irAEs) during an 11-month follow-up. This case indicates that surgeons should carefully inspect the imaging characteristics after immunotherapy and that organ preservation is possible even for patients who fail to achieve complete clinical regression, which is especially important for female patients of childbearing age.

Brief Research Report: Expression of PD-1 and CTLA-4 in T Lymphocytes and Their Relationship With the Periparturient Period and the Endometrial Cytology of Dairy Cows During the Postpartum Period

The present study sought to evaluate the expression of PD-1 and CTLA-4 in blood T lymphocytes during the periparturient period and their relationship with uterine health in dairy cows, as determined by endometrial cytology and serum concentrations of β-hydroxybutyrate (BHB) and non-esterified fatty acids (NEFAs), which are indicators of a negative energy balance. The second objective of this study was to investigate whether the expression of PD-1 and CTLA-4 in T lymphocytes is associated with the serum acute phase-protein haptoglobin concentration during the periparturient period. To address these objectives, 26 clinically healthy dairy cows were used. Peripheral blood was collected 14 days prepartum (T-14), at calving (T0), and 30 days postpartum (T30) to measure the expression of PD-1 and CTLA-4 in blood T lymphocytes by flow cytometry. In addition, we collected blood at T0, 10 days after parturition (T10), and T30 to obtain serum and determine the serum concentrations of NEFA, BHB, and Hp. Endometrial cytology was performed at T10, 20 days after parturition (T20), and T30. In the present study, we observed higher expression of CTLA-4 and PD-1 in T lymphocytes at parturition and in the prepartum period, which could indicate a relationship between these immune checkpoints and immunological tolerance during gestation in dairy cattle. In addition, a negative association between the expression of these immune checkpoints prepartum or at parturition and endometrial cytology at T20 and T30 was observed, indicating the negative implications of these immune response regulators in susceptibility to infections. This finding was further corroborated by the relationship between the serum concentration of haptoglobin and the expression of CTLA-4 and PD-1 by T lymphocytes. However, we did not observe a relationship between the indicators of negative energy balance, evaluated by the serum concentrations of BHB and NEFA, and the expression of the immune checkpoint markers studied. Thus, our findings represent an initial step that paves the way for the development of new therapeutic alternatives directed by the host with the objective of increasing the resistance of dairy cattle to infections in this critical period of life.

Society for Immunotherapy of Cancer (SITC) clinical practice guideline on immunotherapy for the treatment of nonmelanoma skin cancer

Nonmelanoma skin cancers (NMSCs) are some of the most commonly diagnosed malignancies. In general, early-stage NMSCs have favorable outcomes; however, a small subset of patients develop resistant, advanced, or metastatic disease, or aggressive subtypes that are more challenging to treat successfully. Recently, immune checkpoint inhibitors (ICIs) have been approved by the US Food and Drug Administration (FDA) for the treatment of Merkel cell carcinoma (MCC), cutaneous squamous cell carcinoma (CSCC), and basal cell carcinoma (BCC). Although ICIs have demonstrated activity against NMSCs, the routine clinical use of these agents may be more challenging due to a number of factors including the lack of predictive biomarkers, the need to consider special patient populations, the management of toxicity, and the assessment of atypical responses. With the goal of improving patient care by providing expert guidance to the oncology community, the Society for Immunotherapy of Cancer (SITC) convened a multidisciplinary panel of experts to develop a clinical practice guideline (CPG). The expert panel drew on the published literature as well as their own clinical experience to develop recommendations for healthcare professionals on important aspects of immunotherapeutic treatment for NMSCs, including staging, biomarker testing, patient selection, therapy selection, post-treatment response evaluation and surveillance, and patient quality of life (QOL) considerations, among others. The evidence- and consensus-based recommendations in this CPG are intended to provide guidance to cancer care professionals treating patients with NMSCs.

Outcomes after treatment of breast cancer during pregnancy including taxanes and/or granulocyte colony-stimulating factor use: findings from a multi-institutional retrospective analysis

BACKGROUND

Guidelines support comparable treatment for women diagnosed with breast cancer during pregnancy (PrBC) and nonpregnant women with limited case-specific modifications to ensure maternal-fetal safety. Experience during pregnancy with modern agents, such as taxanes or granulocyte colony-stimulating factors (GCSF), is limited.

PATIENTS AND METHODS

We retrospectively identified a multi-institutional cohort of PrBC between 1996 and 2020. Propensity score analyses with multiple imputation for missing variables were applied to determine the associations between chemotherapy exposures during pregnancy, with or without taxanes or GCSF, and a compound maternal-fetal outcome including spontaneous preterm birth, preterm premature rupture of membranes, chorioamnionitis, small for gestational age newborns, congenital malformation, or 5-min Apgar score < 7.

RESULTS

Among 139 PrBC pregnancies, 82 (59.0%) were exposed to chemotherapy, including 26 (31.7%) to taxane and 18 (22.0%) to GCSF. Chemotherapy use, in general, and inclusion of taxane and/or GCSF, specifically, increased over time. Pregnancies resulting in live singleton births (n = 123) and exposed to chemotherapy were as likely to reach term as those that were not (59.5% vs. 63.6%, respectively, p_unadjusted = 0.85). Among women treated with chemotherapy, propensity score-matched odds ratios (OR) for the composite maternal-fetal outcome were not significantly increased with taxane (OR 1.24, 95% CI 0.27-5.72) or GCSF (OR 2.11, 95% confidence interval (CI) 0.48-9.22) with similar effects in multiple imputation and sensitivity models.

CONCLUSION

The judicious increased use of taxane chemotherapy and/or growth factor support during pregnancy was not associated with unfavorable short-term maternal-fetal outcomes. While these findings are reassuring, case numbers remain limited and continued surveillance of these patients and progeny is warranted.

Pregnancy and Tumour: The Parallels and Differences in Regulatory T Cells

Immunological tolerance plays a critical role during pregnancy as semi-allogeneic fetus must be protected from immune responses during the gestational period. Regulatory T cells (Tregs), a subpopulation of CD4+ T cells that express transcription factor Foxp3, are central to the maintenance of immunological tolerance and prevention of autoimmunity. Tregs are also known to accumulate at placenta in uterus during pregnancy, and they confer immunological tolerance at maternal-fetal interface by controlling the immune responses against alloantigens. Thus, uterine Tregs help in maintaining an environment conducive for survival of the fetus during gestation, and low frequency or dysfunction of Tregs is associated with recurrent spontaneous abortions and other pregnancy-related complications such as preeclampsia. Interestingly, there are many parallels in the development of placenta and solid tumours, and the tumour microenvironment is considered to be somewhat similar to that at maternal-fetal interface. Moreover, Tregs play a largely similar role in tumour immunity as they do at placenta- they create a tolerogenic system and suppress the immune responses against the cells within tumour and at maternal-fetal interface. In this review, we discuss the role of Tregs in supporting the proper growth of the embryo during pregnancy. We also highlight the similarities and differences between Tregs at maternal-fetal interface and tumour Tregs, in an attempt to draw a comparison between their roles in these two physiologic and pathologic states.

Effects of Anticoagulants and Immune Agents on Pregnancy Outcomes and Offspring Safety in Frozen-Thawed Embryo Transfer Cycles-A Retrospective Cohort Study

The application of anticoagulants and immune agents in assisted reproduction technology has been in a chaotic state, and no clear conclusion has been reached regarding the effectiveness and safety of this treatment. We aimed to explore the potential association between adjuvant medication and pregnancy outcomes and offspring safety in a retrospective cohort study including 8,873 frozen-thawed embryo transfer cycles. The included cycles were divided into three groups according to the drugs used, namely, the routine treatment group (without anticoagulant agents and immune agents), the anticoagulant agent group, and the immunotherapy group. Among normal ovulatory patients, those who used immune agents had a 1.4-fold increased risk of miscarriage (≤13 weeks), but a 0.8-fold decreased chance of birth (≥28 weeks) compared with the routine treatment group. Among patients with more than 1 embryo transferred, those who used anticoagulant agents showed a 1.2-fold higher risk of multiple birth than those undergoing routine treatment. Among patients without pregnancy complications, anticoagulant treatment was associated with a 2.1-fold increased risk of congenital anomalies. Among young patients (<26 years) with a singleton pregnancy, the neonatal birth weight of the immunotherapy group and the anticoagulant treatment group was 305.4 g and 175.9 g heavier than the routine treatment group, respectively. In conclusion, adjuvant anticoagulants or immune agent treatment in assisted reproductive technology should be used under strict supervision, and the principle of individualized treatment should be followed.