Leflunomide use during pregnancy and the risk of adverse pregnancy outcomes

Use of leflunomide among girls and women of childbearing age and occurrence of leflunomide-exposed pregnancies in Germany

Leflunomide is contraindicated during pregnancy and treatment cessation is recommended two years before pregnancy. We aimed to describe leflunomide use in women of childbearing age in Germany, the occurrence of pregnancies in women using leflunomide and malformations among children possibly exposed in utero. Using the GePaRD database (claims data, ∼20% of the German population), we determined annual age-standardized prevalences of leflunomide use between 2004 and 2019 among females aged 13-49 years. Further, we estimated the number of exposed pregnancies by assessing whether the exposure window assigned to the last dispensation before pregnancy (days covered by the dispensation plus two years) overlapped the onset of pregnancy or whether there was a dispensation in the first eight weeks of pregnancy. For exposed live births, a mother-baby linkage was performed and the presence of congenital malformation was assessed. The age-standardized prevalence of leflunomide use ranged between 0.34 and 0.46 per 1000 females during the study period. About one third of the users were ≤40 years. We identified 205 leflunomide-exposed pregnancies ending during the study period. 71% of these pregnancies ended in a live birth (26% preterm) and 10% in an induced abortion. In 86% of the live births (n=125) the mother-baby linkage was successful. Among these 125 children, 13 children (10%) had congenital malformations. In conclusion, we observed a considerable number of pregnancies in women using leflunomide in the two years before or during early pregnancy. This highlights the importance of monitoring the implementation of existing risk minimization measures for leflunomide in Germany.

Leflunomide exposure through second trimester of pregnancy: A case report

Leflunomide is a commonly used disease modifying antirheumatic agent. However, its use is contraindicated in pregnancy. The American College of Rheumatology (ACR) guidelines recommend discontinuing Leflunomide at least 24 months before conception. If a woman is found to be pregnant while on Leflunomide, ACR suggests close monitoring and cholestyramine washout. We describe a case of a patient with a history of juvenile idiopathic arthritis who was on Leflunomide throughout the first and second trimester of her pregnancy. A cholestyramine washout regimen was started but not completed. The patient was induced at 37 weeks of gestation due to non-reassuring fetal heart rate. She ultimately delivered a healthy baby via emergency cesarian section.

2022 Chinese guideline for the management of pregnancy and reproduction in systemic lupus erythematosus

Systemic lupus erythematosus (SLE), a prevalent autoimmune disease predominantly affecting women of childbearing age, presents ongoing challenges despite notable advances in diagnosis and treatment. Although survival rates for SLE patients have significantly improved, pregnancy continues to pose a considerable obstacle. Addressing this critical need for enhanced reproductive and prenatal care, there is a pressing imperative to establish standardized protocols for peri-gestational monitoring and treatment in SLE patients. This guideline is jointly sponsored by the National Clinical Research Center for Dermatologic and Immunologic Diseases (NCRC-DID), the Chinese Systemic Lupus Erythematosus Treatment and Research Group (CSTAR), and the Chinese Research Committee of Pregnancy and Reproduction in Autoimmune Rheumatic Diseases (CHOPARD). Thirteen pertinent clinical questions have been generated through several rounds of rigorous clinical and methodological expert discussions and selections for a comprehensive understanding of key aspects in this domain. Guided by thorough examination of research evidence and expert perspectives, the formulated recommendations aim to optimize pregnancy success rates, reduce maternal and infant mortality rates, and ultimately enhance the overall well-being of SLE patients.

Pregnancy termination in patients with rheumatic diseases

Rheumatic diseases affect women during their reproductive years. Many women with rheumatic diseases become pregnant; some undergo pregnancy termination. However, there are no official guidelines on pregnancy termination in patients with rheumatic diseases. This paper provides an overview of considerations that healthcare professionals must take into account. We highlight areas that require further studies and the importance of pregnancy planning and contraception counseling. Patients with rheumatic diseases need to be informed of adverse maternal and fetal outcomes of pregnancy to make informed reproductive decisions and reduce the need for pregnancy terminations. This article is protected by copyright. All rights reserved.

The Safety of Medications During Pregnancy and Lactation in Patients with Inflammatory Rheumatic Diseases

The advances in treatments, including disease-modifying anti-rheumatic drugs and biologic agents, have significantly improved the management of inflammatory rheumatic diseases, allowing females with severe disease to become pregnant and lactate, previously considered as prohibited. Maintaining low disease activity with medications known to be safe from pre-conception to post-partum is a key point in reducing adverse pregnancy outcomes. Numerous observational and case studies have provided a growing amount of evidence on the use of safe anti-rheumatic medications in patients during pregnancy and lactation. Based on this information, this review discusses the safety of medications for patients with inflammatory rheumatic diseases during pregnancy and lactation. Among these, hydroxychloroquine, sulfasalazine, azathioprine, low-dose glucocorticoids, and low-dose aspirin are considered compatible with pregnancy, while methotrexate, cyclophosphamide, mycophenolate mofetil, and leflunomide are contraindicated. Non-steroidal anti-inflammatory drugs are only recommended for use early in pregnancy, as they are reported to cause rare but serious kidney problems in the fetus after 20 weeks or later. Cyclosporin, tacrolimus, and anti-TNF agents can be continued throughout pregnancy if the benefit is greater than the potential risk for the individual patient. Physicians should carefully weigh the risks and benefits of medications in patients with inflammatory rheumatic diseases considering pregnancy.

[Current aspects of antirheumatic therapy in pregnancy planning, during pregnancy and breastfeeding]

Active rheumatic disease is a known factor for increased fetomaternal risks during pregnancy. Remission or inactive disease should therefore be targeted to reduce these risks by using pregnancy-compatible antirheumatic drugs as recommended by international guidelines. Teratogenic antirheumatic drugs, such as mycophenolate, methotrexate, cyclophosphamide and thalidomide should be stopped about 3 months prior to conception. Leflunomide is a weak human teratogen that should be stopped and eliminated with cholestyramine prior to conception. Furthermore, drugs with limited data, such as apremilast and JAK inhibitors as well as new biologics should be avoided during gestation. Pregnancy-compatible drugs are the antirheumatic drugs hydroxychloroquine, sulfasalazine, azathioprine, cyclosporine, tacrolimus, colchicine, non-selective NSAIDs, low-dose prednisone/prednisolone and TNF inhibitors. These drugs as well as other biologics, such as rituximab can be used during lactation. In a preconception counselling visit, the benefits and the international recommendations of pregnancy-compatible antirheumatic drugs should be discussed with the patient and be weighed against the possible fetomaternal risks of an active disease to enable a shared decision-making.

Biochemical and clinical predictors in pregnant women with antiphospholipid syndrome and systemic lupus erythematosus: comprehensive update

BACKGROUND

Autoimmune diseases as antiphospholipid syndrome (APS) and systemic lupus erythematosus (SLE) could cause many maternal complications. The most common maternal complications of autoimmune diseases are lupus flare, hypertension, nephritis, preeclampsia (PE), eclampsia, and poor pregnancy outcomes which including preterm delivery and pregnancy loss. Only the lupus anticoagulant in the greatest prospective multicenter study has been associated with adverse pregnancy outcomes of the APS.

PURPOSE

This review aims to provide a comprehensive update for predictors in pregnant women with APS/SLE.

METHODS

These data have been collected from clinical and pathological studies, systematic reviews, and meta-analysis.

RESULTS

In recent years the SLE and APS demonstrated to have different and valuable clinical and biomarker predictors for the pregnancy outcome. Treatment of pregnant women with APS is low molecular weight heparin (LMWH) and aspirin; however, around 75% of this management is considered successful.

CONCLUSION

This review summarizes recent research that focuses on biochemical and clinical predictors of adverse pregnancy outcomes (APOs) of pregnant women with SLE and APS. Furthermore, we have collected more evidence that confirms the safety and efficacy of hydroxychloroquine (HCQ) preventing APOs.

Antirheumatic medications in pregnancy and breastfeeding

PURPOSE OF REVIEW

As active rheumatic and musculoskeletal disease during pregnancy increases the risk for pregnancy loss, preterm birth, and maternal illness, ongoing management with pregnancy-compatible medications can improve these outcomes. Selecting and taking these medications can be challenging for rheumatologists and patients due to limited knowledge about potential risks and benefits.

RECENT FINDINGS

Fortunately, the American College of Rheumatology, American College of Obstetrics and Gynecology, British Rheumatology Society, and the European League Against Rheumatism have each published recommendations to guide the use of antirheumatic medications in pregnancy and lactation. Each of these groups endorsed the use of hydroxychloroquine, azathioprine, sulfasalazine, corticosteroids, NSAIDs, and tumor necrosis factor inhibitors in pregnancy. They also agreed that methotrexate, mycophenolate, cyclophosphamide, and leflunomide should be avoided in pregnancy. New medications, including small-molecules and biologics, have limited data to support safety in pregnancy and are not currently recommended during this period. Most antirheumatic medications are compatible with lactation.

SUMMARY

Because many patients are hesitant to use antirheumatic medications during pregnancy, honest and accurate discussions about pregnancy planning and management are important to help women make decisions that are in their and their offspring's best interest.

Conventional disease-modifying agents in rheumatoid arthritis - a review of their current use and role in treatment algorithms

Despite the development of targeted therapies, conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) remain the cornerstone of treatment of rheumatoid arthritis (RA). A literature search was conducted on treatment recommendations and relevant papers regarding new insights on therapeutics in rheumatoid arthritis. Methotrexate is considered the “anchor drug” due to its high efficacy as monotherapy and in combination with other conventional and targeted agents. Leflunomide and sulfasalazine are sound alternatives, whereas (hydroxy)chloroquine is primarily used in combination with other csDMARDs.

Their use is encouraged in all treatment phases – in combination with targeted agents, and with other csDMARDs. Combining different csDMARDs is especially attractive in lower income settings given the evidence proving (almost) equal efficacy and safety of the csDMARD combination approach compared to the combination of targeted agents with a csDMARD.

The aim of this review is to provide a clinically oriented insight into the pharmacology of each csDMARD and their place in treatment algorithms.

Update on pregnancy complications in systemic lupus erythematosus

PURPOSE OF REVIEW

This review summarizes recent research in the field of systemic lupus erythematosus (SLE) and pregnancy with focus on clinical and biochemical predictors of adverse pregnancy outcomes (APOs), accumulating evidence for the safety and efficacy of hydroxychloroquine (HCQ) in pregnancy, and the importance of preconception counseling.

RECENT FINDINGS

Ongoing research from PROMISSE investigators (Predictors of Pregnancy Outcome: Biomarkers in Antiphospholipid Antibody Syndrome and Systemic Lupus Erythematosus) adds to the understanding of risk factors for APOs in SLE pregnancies, including aberrant complement activation, incomplete downregulation of lupus-associated transcription factors, and lower socioeconomic status. Evidence supporting numerous advantages for continuing HCQ in pregnancy, as well as support for low-dose aspirin in preeclampsia prevention is reviewed. Practice gaps exist among rheumatologists in ensuring effective contraception when women of childbearing age are undergoing therapy with potentially fetotoxic medications. The publication of organizational guidelines provides evidence-based recommendations on lupus pregnancy management.

SUMMARY

Outcomes of lupus pregnancies continue to improve with understanding of risk factors that predict APOs as well as improvements in disease management. Rheumatologists caring for women with SLE should be familiar with the most up-to-date research in order to optimize pregnancy outcomes in this population.

Placental transfer and safety in pregnancy of medications under investigation to treat coronavirus disease 2019

Objective

Treatment of coronavirus disease 2019 is mostly symptomatic, but a wide range of medications are under investigation against severe acute respiratory syndrome coronavirus 2. Although pregnant women are excluded from clinical trials, they will inevitably receive therapies whenever they seem effective in nonpregnant patients and even under compassionate use.

Methods

We conducted a review of the literature on placental transfer and pregnancy safety data of drugs under current investigation for coronavirus disease 2019.

Results

Regarding remdesivir, there are no data in pregnant women. Several other candidates already have safety data in pregnant women, because they are repurposed drugs already used for their established indications. Thus, they may be used in pregnancy, although their safety in the context of coronavirus disease 2019 may differ from conventional use. These include HIV protease inhibitors such as lopinavir/ritonavir that have low placental transfer, interferon that does not cross the placental barrier, and hydroxychloroquine or chloroquine that has high placental transfer. There are also pregnancy safety and placental transfer data for colchicine, steroids, oseltamivir, azithromycin, and some monoclonal antibodies. However, some drugs are strictly prohibited in pregnancy because of known teratogenicity (thalidomide) or fetal toxicities (renin-angiotensin system blockers). Other candidates including tocilizumab, other interleukin 6 inhibitors, umifenovir, and favipiravir have insufficient data on pregnancy outcomes.

Conclusion

In life-threatening cases of coronavirus disease 2019, the potential risks of therapy to the fetus may be more than offset by the benefit of curing the mother. Although preclinical and placental transfer studies are required for a number of potential anti-severe acute respiratory syndrome coronavirus 2 drugs, several medications can already be used in pregnant women.

Effectiveness and safety of leflunomide compared with cyclophosphamide as induction therapy in Takayasu's arteritis: an observational study

Aims

The objective of this study was to investigate the outcomes of leflunomide (LEF) compared with those of cyclophosphamide (CYC) as induction against active Takayasu's arteritis (TA) in Chinese patients.

Methods

This was an observational study based on a prospective cohort that included TA patients diagnosed in large third-level first-class general hospitals in East China from January 2009 to September 2018. LEF- or CYC-induced active patients were enrolled for comparative effectiveness analysis. One-to-more paired cohorts of LEF versus CYC were derived by propensity-score matching (PSM). The primary outcome was complete remission (CR) at 9-month follow up, and secondary endpoints included partial remission (PR) and effectiveness rate (ER). Multivariable logistic regression was used to identify statistical significance.

Results

A total of 131 enrolled patients with at least 3-months treatment included 53 receiving a regimen of glucocorticoid (GC) and LEF and 78 receiving GC and CYC. Compared with the CYC group, the LEF group showed higher CR rate {LEF versus CYC: 84.6% [95% confidence interval (CI) 74.5-94.8%] versus 59.0% (47.8-70.1%); relative risk (RR) = 0.3 (0.1-0.6), p = 0.002} and lower daily GC dose [10.0 (5.0-12.5) versus 12.5 (10.0-15.0) mg, p = 0.043] at the end of the 9-month induction. In the matched analysis, the LEF group (n = 23) still indicated a higher CR rate than the CYC group (n = 54) after PSM [RR = 0.1 (0.0-0.6), p = 0.003]. Four LEF-treated patients had mild side effects, and one died unrelated to LEF.

Conclusion

LEF could be an alternative induction therapy against TA, showing good effectiveness and tolerance compared with CYC.

Efficacy and safety of leflunomide versus cyclophosphamide for initial-onset Takayasu arteritis: a prospective cohort study

BACKGROUND

Leflunomide (LEF) has been considered as an alternative treatment for Takayasu arteritis (TA); however, data on its efficacy are still scanty.

OBJECTIVE

To investigate the efficacy and safety of LEF versus cyclophosphamide (CYC) for initial-onset TA.

METHODS

Initial-onset TA patients with active disease were enrolled in this research. Patients enrolled from 1 January 2009 to 31 December 2015 were treated with glucocorticoids and CYC, while patients enrolled from 1 January 2016 to 31 October 2018 received glucocorticoids and LEF. Treatment response including complete remission (CR), partial remission (PR), and effectiveness rate (ER) and side effects were evaluated at 6 and 12 months.

RESULTS AND CONCLUSION

In total, 92 patients were enrolled. A total of 47 patients were treated with LEF, while 45 patients were treated with CYC. The CR and ER rates were 75.55%, and 88.89% at 6 months, and 85.37% and 95.12% at 12 months in the LEF group. The CR and ER rates were 39.02% and 70.73% at 6 months, and 56.41% and 82.05% at 12 months in the CYC group. The CR rate was significantly higher in the LEF group than in the CYC group both at 6 months (75.61% versus 38.24%, p < 0.01) and 12 months (77.42% versus 53.33%, p < 0.05) after adjustment for propensity scores. The incidence of side effects in the LEF group was much lower than that in the CYC group (21.28% versus 44.44%). In conclusion, LEF provided a better treatment response, along with lower reproductive toxicity, compared with CYC in initial-onset TA.

Pregnancy outcomes in patients treated with leflunomide, the parent compound of the multiple sclerosis drug teriflunomide

Leflunomide is contraindicated in pregnant women, yet human data from leflunomide-exposed pregnancies do not indicate an embryofetal toxicity signal. The objective of the present analysis was to report pregnancy outcomes for leflunomide-exposed pregnancies in clinical trials and in the post-marketing setting. Pregnancy outcomes are summarized from leflunomide clinical trials and the post-marketing setting. The data cut-off was 31 December 2017. Of 1167 pregnancies reported in female patients exposed to leflunomide, 587 had a known outcome. Of these, 337 (57.4%) were reported prospectively and 250 (42.6%) were reported retrospectively. Of the 587 pregnancies with a known outcome (which involved 15 sets of twins), there were 333 (56.7%) live births, with 285 (48.6%) full-term births and 48 (8.2%) pre-term births. Birth defects were reported in 44 babies/fetuses/embryos from 587 pregnancies, with 2 reporting at least 3 minor defects and 20 reporting major defects. Major defects were reported in 3 of 337 (0.9%) prospectively-reported pregnancies; 1 major birth defect occurred in a live birth, and 2 were electively terminated due to a detected fetal anomaly. Two of the babies/fetuses/embryos, a live birth and an electively aborted baby/fetus/embryo, from 206 prospectively-reported pregnancies exposed to leflunomide during the first trimester experienced major defects. Birth defects showed no specific patterns and were distributed evenly across organ systems. Outcomes were consistent with the general population. These findings do not suggest an embryofetal toxicity signal for leflunomide, which is consistent with previous findings from leflunomide-exposed pregnancies.

The role of immunosuppressive agents in the management of severe and refractory immune-related adverse events

The advent of immune checkpoint inhibitors has improved survival in some types of cancer and brought promising prospects to cancer immunotherapy. Despite their clinical benefits, significant off-target toxicities resulting from the immune system activation have been observed, namely immune-related adverse events (irAEs), which pose to clinicians a new challenge of optimal management. With steroids being the mainstay of current management of irAEs, immunosuppressive agents are especially indicated for severe or steroid-refractory cases, based on current immunopathophysiological knowledge and on extrapolations of treatment options for primary autoimmune disorders. This review focuses on the status and recent clinical progress of immunosuppressive agents in the management of severe and steroid-refractory irAEs.

2020 American College of Rheumatology Guideline for the Management of Reproductive Health in Rheumatic and Musculoskeletal Diseases

OBJECTIVE

To develop an evidence-based guideline on contraception, assisted reproductive technologies (ART), fertility preservation with gonadotoxic therapy, use of menopausal hormone replacement therapy (HRT), pregnancy assessment and management, and medication use in patients with rheumatic and musculoskeletal disease (RMD).

METHODS

We conducted a systematic review of evidence relating to contraception, ART, fertility preservation, HRT, pregnancy and lactation, and medication use in RMD populations, using Grading of Recommendations Assessment, Development and Evaluation methodology to rate the quality of evidence and a group consensus process to determine final recommendations and grade their strength (conditional or strong). Good practice statements were agreed upon when indirect evidence was sufficiently compelling that a formal vote was unnecessary.

RESULTS

This American College of Rheumatology guideline provides 12 ungraded good practice statements and 131 graded recommendations for reproductive health care in RMD patients. These recommendations are intended to guide care for all patients with RMD, except where indicated as being specific for patients with systemic lupus erythematosus, those positive for antiphospholipid antibody, and/or those positive for anti-Ro/SSA and/or anti-La/SSB antibodies. Recommendations and good practice statements support several guiding principles: use of safe and effective contraception to prevent unplanned pregnancy, pre-pregnancy counseling to encourage conception during periods of disease quiescence and while receiving pregnancy-compatible medications, and ongoing physician-patient discussion with obstetrics/gynecology collaboration for all reproductive health issues, given the overall low level of available evidence that relates specifically to RMD.

CONCLUSION

This guideline provides evidence-based recommendations developed and reviewed by panels of experts and RMD patients. Many recommendations are conditional, reflecting a lack of data or low-level data. We intend that this guideline be used to inform a shared decision-making process between patients and their physicians on issues related to reproductive health that incorporates patients' values, preferences, and comorbidities.

Update of the Mexican College of Rheumatology Guidelines for the Pharmacological Treatment of Rheumatoid Arthritis, 2018

Therapeutic advances in rheumatoid arthritis require periodic review of treatment guidelines.

OBJECTIVE

To update the Mexican College of Rheumatology guidelines on the pharmacological treatment of rheumatoid arthritis.

METHOD

Board certified rheumatologists from different health institutions and regions of the country participated. Work teams were formed that reviewed the previous guidelines, elaborated new questions, reviewed the literature, and scored the evidence that was presented and discussed in plenary session. The conclusions were presented to infectologists, gynaecologists and patients. Recommendations were based on levels of evidence according to GRADE methodology.

RESULTS

Updated recommendations on the use of available medications for rheumatoid arthritis treatment in Mexico up to 2017 are presented. The importance of adequate and sustained control of the disease is emphasized and relevant safety aspects are described. Bioethical conflicts are included, and government action is invited to strengthen correct treatment of the disease.

CONCLUSIONS

The updated recommendations of the Mexican College of Rheumatology on the pharmacological treatment of rheumatoid arthritis incorporate the best available information to be used in the Mexican health care system.

Immunosuppressives and biologics during pregnancy and lactation : A consensus report issued by the Austrian Societies of Gastroenterology and Hepatology and Rheumatology and Rehabilitation

An increasing and early-onset use of immunosuppressives and biologics has become more frequently seen among patients with inflammatory bowel diseases (IBD) and rheumatic disorders. Many women in their childbearing years currently receive such medications, and some of them in an interdisciplinary setting. Many questions arise in women already pregnant or wishing to conceive with respect to continuing or discontinuing treatment, the risks borne by the newborns and their mothers and long-term safety. Together with the Austrian Society of Rheumatology and Rehabilitation, the IBD working group of the Austrian Society of Gastroenterology and Hepatology has elaborated consensus statements on the use of immunosuppressives and biologics in pregnancy and lactation. This is the first Austrian interdisciplinary consensus on this topic. It is intended to serve as a basis and support for providing advice to our patients and their treating physicians.

Fetal Toxicity of Immunosuppressive Drugs in Pregnancy

Women affected by autoimmune diseases, organ transplantation, or neoplasia need to continue immunosuppressive treatment during pregnancy. In this setting, not only a careful planning of pregnancy, but also the choice of drugs is critical to preventing maternal complications and minimizing the fetal risks. Some immunosuppressive drugs are teratogenic and should be replaced even before the pregnancy, while other drugs need to be managed with caution to prevent fetal risks, including miscarriage, intrauterine growth restriction, prematurity, and low birth weight. In particular, the increasing use of biologic agents raises the question of their compatibility with reproduction. In this review we present data on the indication and safety in pregnancy of the most frequently used immunosuppressive drugs.

Practical Evidence-Based Recommendations for Patients with Multiple Sclerosis Who Want to Have Children

Multiple sclerosis (MS) management presently aims to reach a state of no (or minimal) evidence of disease activity. The development and commercialization of new drugs has led to a renewed interest in family planning, since patients with MS may face a future with reduced (or no) disease-related neurological disability. The advice of neurologists is often sought by patients who want to have children and need to know more about disease control at conception and during pregnancy and the puerperium. When MS is well controlled, the simple withdrawal of drugs for patients who intend to conceive is not an option. On the other hand, not all treatments presently recommended for MS are considered safe during conception, pregnancy and/or breastfeeding. The objective of the present study was to summarize the practical and evidence-based recommendations for family planning when our patients (women and men) have MS.Funding TEVA Pharmaceutical Brazil.

Use of synthetic and biologic DMARDs during pregnancy

Introduction: Since most of the autoimmune diseases (AID) affect mostly women in their fertile years, and fertility is in general preserved, the use of disease-modifying antirheumatic drugs (DMARDs) during conception, pregnancy, and lactation has been a matter of concern in the treatment of women affected by AID. Areas covered: We performed a comprehensive review of the latest and most relevant research papers published in the field and discussed different aspects related to the use of synthetic and biologic DMARDs and immunosuppressants in the preconceptional period, during pregnancy and lactation in AID patients, both in males and females. Expert commentary: Active AID impose an increased risk for adverse maternal and fetal outcomes, such as preeclampsia, miscarriage, intrauterine growth restriction, prematurity, low birth weight, and stillbirth. Family planning with proper contraception and shared decision-making on the ideal time to conceive with treatment adjustment must be a rule. One of the main challenges when counseling and/or adjusting treatment of patients that are planning a pregnancy is to provide a medication that is at the same time efficacious and safe at the conceptional period and to developing the fetus.