Allylestrenol

Approximately half of the patients with threatened miscarriage suffer an abortion, and consistent medication therapy to prevent threatened miscarriage is lacking. Our goal was to investigate the real-world pharmacological treatment patterns of patients with threatened miscarriage in China, with a focus on the trend and rationality of progestogen use over the last 7 years.

We performed a cross-sectional analysis of data from the Hospital Prescription Analysis Cooperation Project that is overseen by the Chinese Pharmaceutical Association. Information was extracted from prescriptions of outpatients with threatened miscarriage between January 2014 and December 2020. We quantified the types of medications using the first level anatomical therapeutic chemical (ATC) classification code and the frequency of use of medicines classified as category X by the United States Food and Drug Administration (FDA). We also calculated the prevalence of the most frequently used progestogens by assessing prescription rates, determined the sum of the defined daily doses (DDDs) and defined daily cost (DDC) and evaluated the rationality of progestogens according to drug labels and guidelines.

Of the 91,464 patients included in this study, 69.4% were from the eastern region, 92.5% were from tertiary hospitals, and 72.9% were between 25 and 34 years old. The average number of medications per patient was 1.4. The following types of medicines were the most prevalent: "genitourinary system and sex hormones" (90.7%), "alimentary tract and metabolism" (10.8%) and "blood and blood-forming organs" (9.9%). Progestogens were prescribed for 81,080 patients (88.6%), among which oral progesterone (39.7%) was the most commonly used, followed by oral dydrogesterone (34.4%), progesterone injection (26.0%), oral allylestrenol (0.7%) and progesterone gel (0.4%). In other words, 10,991 (12.0%) patients used more than one progestogen, and the top three combinations were oral dydrogesterone plus progesterone injection (5.6%), oral progesterone plus progesterone injection (4.7%) and oral dydrogesterone plus oral progesterone (1.1%). The prescription rate of dydrogesterone increased gradually, whereas that of progesterone, especially progesterone injection, obviously decreased. Among 34,760 prescriptions of progestogens with complete usage information, the primary errors of progestogen use were "low frequency" (18.4%), "high single dose" (15.9%) and "low single dose" (11.3%). In addition, 137 prescriptions were identified with drug-progestogen interactions, and 61 were identified with contraindications for progestogens. A total of 4.5% of prescriptions included FDA category X medicines.

Our findings are the first to provide information on medication use in patients with threatened miscarriage over the last seven years in China. Medicines targeting the "genitourinary system and sex hormones," especially progestogens, were the most commonly prescribed medications, among which dydrogesterone was the most prevalent. However, it is remarkable that the use of progestogens for the treatment of threatened abortion is still controversial; thus, high-quality large sample studies are still required, especially among Chinese patients. Since usage errors in progestogen records and exposure to category X medicines were common, more efforts are needed to guarantee the safety and rationality of medicines used in pregnant women.

Indirect and unsymmetrical indirect covariance NMR provide powerful tools to compute and visualize correlation information by transforming component spectra into combined spectral data matrices. Sensitive component spectra such as TOCSY, HSQC and NOESY can be quickly converted into experimentally insensitive or time‐consuming correlation spectra such as HSQC‐NOESY. The comparison of illustrative series of spectra from four steroids, dexamethasone, testosterone, allylestrenol and tibolone, renders the effects of resonance overlap on the ease of interpretation visible. The compounds are selected such that signal overlap increases systematically in the proton and carbon domain. Spectra are defined as light, moderate and heavy signal overlap, based on signal density. The investigation suggests that moderate spectral congestion in either proton or carbon domain leads to a number of artifacts that does not hamper signal assignment but lowers the level of confidence on de novo structure elucidation. Since the number of correlations usually increases through covariance processing, component spectra with severe spectral congestion in both dimensions are not suitable for covariance processing and the resulting spectra do not support structure confirmation or structure elucidation. The calculated spectra are compared with the corresponding experimental spectra with respect to their application in structure elucidation laboratory environments. Copyright © 2011 John Wiley & Sons, Ltd.