To analyze the susceptibility of SARS-CoV-2 in pregnancy and the drugs that can be used to treat pregnancy with COVID-19, so as to provide evidence for drug selection in clinic. By reviewing the existing literature, this paper analyzes the susceptibility of pregnant women to virus, especially to SARS-CoV-2, from the aspects of anatomical, reproductive endocrine and immune changes during pregnancy and screens effective and fetal-safe treatments from the existing drugs. The anatomical structure of the respiratory system is changed during pregnancy, and the virus transmitted by droplets and aerosols is more easily inhaled by pregnant women and is difficult to remove. Furthermore, the prognosis is worse after infection when compared with non-pregnancy women. And changes in reproductive hormones and immune systems during pregnancy collectively make them more susceptible to certain infections. More importantly, angiotensin-converting enzyme (ACE)-2, the SARS-CoV-2 receptor, has been proven highly increased during pregnancy, which may contribute to the susceptibility to SARS-CoV-2. When it comes to treatment, specific drugs for COVID-19 have not been found at present, and taking old drugs for new use in treating COVID-19 has become an emergency method for the pandemic. Particularly, drugs that show superior maternal and fetal safety are worthy of consideration for pregnant women with COVID-19, such as chloroquine, metformin, statins, lobinavir/ritonavir, glycyrrhizic acid, and nanoparticle-mediated drug delivery (NMDD), etc. Pregnant women are susceptible to COVID-19, and special attention should be paid to the selection of drugs that are both effective for maternal diseases and friendly to the fetus. However, there are still many deficiencies in the study of drug safety during pregnancy, and broad-spectrum, effective and fetal-safe drugs for pregnant women need to be developed so as to cope with more infectious diseases in the future.

The increasing use of traditional herbal medicines around the world requires more scientific evidence for their putative harmlessness. To this end, a plethora of methods exist, more or less satisfying. In this post-genome era, recent reviews are however scarce, not only on the use of new "omics" methods (transcriptomics, proteomics, metabonomics) for genotoxicity, teratogenicity, and nephrotoxicity assessment, but also on conventional ones. The present work aims (i) to review conventional methods used to assess genotoxicity, teratogenicity and nephrotoxicity of medicinal plants and mushrooms; (ii) to report recent progress in the use of "omics" technologies in this field; (iii) to underline advantages and limitations of promising methods; and lastly (iv) to suggest ways whereby the genotoxicity, teratogenicity, and nephrotoxicity assessment of traditional herbal medicines could be more predictive. Literature and safety reports show that structural alerts, in silico and classical in vitro and in vivo predictive methods are often used. The current trend to develop "omics" technologies to assess genotoxicity, teratogenicity and nephrotoxicity is promising but most often relies on methods that are still not standardized and validated. Hence, it is critical that toxicologists in industry, regulatory agencies and academic institutions develop a consensus, based on rigorous methods, about the reliability and interpretation of endpoints. It will also be important to regulate the integration of conventional methods for toxicity assessments with new "omics" technologies.

Background: Early pregnancy loss (EPL) is a frustrating clinical problem, whose mechanisms are not completely understood. DNA methylation, which includes maintenance methylation and de novo methylation directed by DNA methyltransferases (DNMTs), is important for embryo development. Abnormal function of these DNMTs may have serious consequences for embryonic development. Methods: To evaluate the possible involvement of DNA methylation in human EPL, the expression of DNMT proteins and global methylation of DNA were assessed in villous or decidua from EPL patients. The association of maintenance methylation with embryo implantation and development was also examined. Results: We found that DNMT1 and DNMT3A were both expressed in normal human villous and decidua. DNMT1 expression and DNA global methylation levels were significantly down-regulated in villous of EPL. DNMT3A expression was not significantly changed in the EPL group compared to controls in either villous or decidua. We also found that disturbance of maintenance methylation with a DNMT1 inhibitor may result in a decreased global DNA methylation level and impaired embryonic development in the mouse model, and inhibit in vitro embryo attachment to endometrial cells. Conclusions: Our results demonstrate that defects in DNA maintenance methylation in the embryo, not in the mother, are associated with abnormal embryonic implantation and development. The findings of the current study provide new insights into the etiology of EPL.

Objective. To explore the effects of overweight and obesity on the outcomes of in vitro fertilisation (IVF) in Chinese infertile patients. Study design. A retrospective cohort study was carried out in 2222 normal weight (18.5 ≤ BMI < 25), 379 overweight (25 ≤ BMI < 30) and 27 obese (BMI ≥ 30) women who underwent their first IVF cycles between 2002 and 2008. Cycle characteristics and IVF outcomes were analysed. Results. Obese women required significantly higher dose of rFSH (3272 IU vs. 2587 IU, p < 0.001) and days of stimulation (11.89 ± 4.57 vs. 10.42 ± 2.03, p < 0.001), but exhibited less oocytes retrieved and significantly lower fertilisation rate (54.1% vs. 61.1%, p < 0.001) than normal weight women. Compared with normal weight women, overweight women displayed significantly less oocytes retrieved (12.98 ± 6.91 vs. 14.49 ± 7.96, p < 0.001), lower fertilisation rate (60.8 ± 23.3 vs. 61.1 ± 23.0, p < 0.001), less cleavaged embryos (7.55 ± 4.86 vs. 8.67 ± 5.90, p < 0.001), less high-grade embryos (4.65 ± 3.96 vs. 5.59 ± 4.81, p < 0.001) and cryopreserved embryos (4.44 ± 4.55 vs. 5.49 ± 5.55, p < 0.001). All parameters of pregnancy outcomes, including pregnancy rate, miscarriage rate and live birth rate, were comparable among three groups. Conclusions. Overweight and obesity are related with impared ovarian response, and negatively affect the outcomes of IVF.