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The injectable progestin depot-medroxyprogesterone acetate (DMPA) is a popular contraceptive choice in sub-Saharan Africa although mouse models indicate it weakens genital epithelial integrity and barrier function and increases susceptibility to genital infection. The intravaginal ring NuvaRing® is another contraceptive option that like DMPA suppresses hypothalamic pituitary ovarian (HPO) axis function with local release of progestin (etonogestrel) and estrogen (ethinyl estradiol). As we previously reported that treating mice with DMPA and estrogen averts the loss of genital epithelial integrity and barrier function induced by DMPA alone, in the current investigation we compared genital levels of the cell-cell adhesion molecule desmoglein-1 (DSG1) and genital epithelial permeability in rhesus macaques (RM) treated with DMPA or a NuvaRing®re-sized for RM (N-IVR). While these studies demonstrated comparable inhibition of the HPO axis with DMPA or N-IVR, DMPA induced significantly lower genital DSG1 levels and greater tissue permeability to intravaginally administered low molecular mass molecules. By identifying greater compromise of genital epithelial integrity and barrier function in RM administered DMPA vs. N-IVR, our results add to the growing body of evidence that indicate DMPA weakens a fundamental mechanism of anti-pathogen host defense in the female genital tract.

The article delves into the significance of recognizing variations among direct-acting oral anticoagulants (DOACs) when treating patients with epilepsy, particularly in relation to concomitant antiseizure medications (ASMs). It suggests that edoxaban may be the preferred DOAC for patients with epilepsy, especially when paired with mild to moderate CYP3A-inducing ASMs. The study also cautions about potential interactions with CYP3A4/P-gp inhibiting ASMs, advising careful monitoring, especially with cannabidiol. Additionally, the article explores the association between non-vitamin K oral anticoagulants and the risk of major bleeding in patients with nonvalvular atrial fibrillation, emphasizing the importance of assessing drug interactions for effective and safe treatment. [Extracted from the article]

Background and Objective: Firsocostat is an oral, liver-targeted inhibitor of acetyl-CoA carboxylase in clinical development for the treatment of metabolic dysfunction-associated steatohepatitis. This work evaluated the potential drug–drug interactions (DDIs) of firsocostat as a victim and as a perpetrator, to inform concomitant medication use. Methods: In this phase I study, healthy participants (n = 13–30 in each of four cohorts) received firsocostat alone or in combination with either victims or perpetrators of cytochrome P450 (CYP) enzymes and drug transporters to evaluate firsocostat as both a victim and perpetrator of DDIs, respectively. Results: Overall, 80 participants completed the study. As a victim of DDI, firsocostat plasma exposure (area under the plasma concentration-time curve [AUC] from 0 to infinity [AUC∝]) was 19-fold, 22-fold, 63%, and 38% higher when administered with single-dose rifampin 600 mg (organic anion transporting polypeptide [OATP] 1B1/B3 inhibitor), single-dose cyclosporine A 600 mg (OATP/P-glycoprotein/CYP3A inhibitor), multiple-dose probenecid 500 mg twice daily (evaluated as a uridine diphosphate glucuronosyltransferase [UGT] inhibitor), and multiple-dose voriconazole 200 mg twice daily (CYP3A inhibitor), respectively, compared with the administration of firsocostat alone. As a perpetrator of DDI, multiple-dose administration of firsocostat did not affect the exposure of midazolam 2 mg (CYP3A substrate) or drospirenone/ethinylestradiol 3 mg/0.02 mg (combined oral contraceptive). Study treatments were well-tolerated and all adverse events were mild. Conclusions: Firsocostat can be administered with CYP3A and UGT inhibitors without dose adjustment. However, firsocostat should not be coadministered with strong OATP1B/3 inhibitors, such as rifampin and cyclosporine A. Firsocostat can be administered with CYP3A substrates or combined oral contraceptives without dose modification. [ABSTRACT FROM AUTHOR]

AbstractObjectiveMethodResultsConclusionTrial registrationThis study aimed to assess the efficacy of randomly started oral dienogest/ethinylestradiol (DNG/EE) for swift endometrial preparation prior to outpatient hysteroscopic polypectomy in perimenopausal women.A multicenter, prospective, randomized controlled trial was conducted in university hospitals. Eighty perimenopausal women scheduled for outpatient hysteroscopic polypectomy between January 2023 and March 2024 were randomly assigned to either intervention (n = 40) or control (n = 40) groups. Exclusion criteria included concomitant endometrial pathologies, recent therapy and adnexal diseases. The intervention group received oral DNG/EE 2 mg/0.03 mg/day started on any day of the menstrual cycle for 14 days. The control group underwent polypectomy between menstrual cycle days 8 and 11 without pharmacological treatment.Pre-procedure (p < 0.001) and post-procedure (p < 0.001) endometrial thickness were significantly reduced in the intervention group, along with a higher incidence of hypotrophic/atrophic endometrial patterns (p < 0.001). Surgical parameters also differed significantly between groups.DNG/EE treatment offers rapid, cost-effective endometrial preparation, enhancing surgical outcomes and patient satisfaction during outpatient polypectomy.ClinicalTrials.gov NCT06316206. [ABSTRACT FROM AUTHOR]

Dysmenorrhea treatment with 0.5 mg dienogest tablets twice daily (1 mg/day) has proven useful, but its effect on premenstrual disorders has not yet been evaluated. This study aimed to evaluate the efficacy of 0.5 mg dienogest tablets in relieving premenstrual syndrome (PMS)-like symptoms during the treatment of dysmenorrhea in comparison with that of continuous low-dose estrogen–progestin (LEP/COC) drospirenone/ethinylestradiol combination, which is considered effective in treating premenstrual dysphoric disorder. During the standard course of dysmenorrhea treatment with dienogest or LEP/COC, PMS-like symptoms were scored based on patients' reports, and the treatment effects were compared. As a result, the dienogest group experienced a significant improvement in PMS-like symptoms compared with the LEP/COC group over the 6-month study period (p < 0.01). Furthermore, dienogest was more effective in providing relief from PMS-like symptoms, with 89.7% of patients reporting a complete resolution of PMS-like symptoms at 6 months, compared with 47.1% in the LEP/COC group (p < 0.01). These results indicate that dienogest is effective in relieving PMS-like symptoms, similar to LEP/COC. Further studies are needed to determine whether 0.5 mg dienogest tablets, which are only available in Japan, are effective in treating premenstrual disorders diagnosed via standard methods. [ABSTRACT FROM AUTHOR]

A drug–drug interaction (DDI) study was conducted to evaluate the effect of icenticaftor (QBW251) on the pharmacokinetics (PK) of a 5‐probe cytochrome P450 (CYP) substrate cocktail, guided by in vitro studies in human hepatocytes and liver microsomes. Another DDI study investigated the effect of icenticaftor on the PK and pharmacodynamics (PD) of a monophasic oral contraceptive (OC) containing ethinyl estradiol (EE) and levonorgestrel (LVG) in premenopausal healthy female subjects. The static‐mechanistic DDI assessment indicated that icenticaftor may moderately induce the metabolic clearance of co‐medications metabolized by CYP3A4 (area under the concentration–time curve [AUC] ratio: 0.47) and potentially CYP2C; icenticaftor may also weakly inhibit the metabolic clearance of co‐medications metabolized by CYP1A2 and CYP3A4 (AUC ratio: 1.35 and 1.86, respectively) and moderately inhibit CYP2B6 (AUC ratio: 2.11). In the CYP substrate cocktail DDI study, icenticaftor 300 mg twice daily (b.i.d.) moderately inhibited CYP1A2 (AUC ratio: 3.35) and CYP2C19 (AUC ratio: 2.70). As expected from the results of the in vitro studies, weak induction was observed for CYP3A4 (AUC ratio: 0.51) and CYP2C8 (AUC ratio: 0.66). In the OC DDI study, co‐administration of icenticaftor 450 mg b.i.d. with monophasic OC containing 30‐μg EE and 150‐μg LVG once daily reduced the plasma exposure of both components by approximately 50% and led to increased levels of follicle‐stimulating hormone and luteinizing hormone. These results provide valuable guidance for the use of icenticaftor in patients taking concomitant medications that are substrates of CYP enzymes or patients using OCs. [ABSTRACT FROM AUTHOR]

Objective: To analyze the efficacy of levonorgestrelintrauterine system, Drospirenone & ethinylestradiol tablets (II), and dydrogesterone in preventing the recurrence of endometrial polyps after hysteroscopic endometrial polypectomy. Methods: One hundred seventy patients who underwent hysteroscopic endometrial polypectomy in the Gynecology Department of Tianmen First People's Hospital in Hubei Province from January 2022 to June 2023 were randomly divided into the levonorgestrelintrauterine system group, Drospirenone & ethinylestradiol tablets (II) group, dydrogesterone group, and a control group. The recurrence rates, endometrial thickness, and menstrual volume changes at 6 and 12 months post-operation were compared among these four groups. Results: The recurrence rates in the levonorgestrelintrauterine system group, Drospirenone & ethinylestradiol tablets (II) group, and dydrogesterone group were lower than the control group, with statistical significance (P < 0.01), with the levonorgestrelintrauterine system group having the lowest recurrence rate. The endometrial thickness at 6 and 12 months post-operation in the levonorgestrelintrauterine system group, Drospirenone & ethinylestradiol tablets (II) group, and dydrogesterone group was thinner than that of the control group and thinner than pre-operation, with statistical significance (P < 0.01). The menstrual volume at 3 months post-operation in the levonorgestrelintrauterine system group, Drospirenone & ethinylestradiol tablets (II) group, and dydrogesterone group was significantly less than the control group, and less than the pre-operation volume. Conclusion: Dydrogesterone, drospirenone & ethinylestradiol tablets (II), and levonorgestrelintrauterine system all play a role in preventing the recurrence of endometrial polyps, but levonorgestrelintrauterine system is significantly better than dydrogesterone and Drospirenone & ethinylestradiol tablets (II) in terms of postoperative recurrence rate, endometrial thickness, menstrual changes, and compliance, and is worth promoting in clinical application. [ABSTRACT FROM AUTHOR]

Background: Venous thromboembolism (VTE) poses a significant global health challenge, notably exacerbated by the use of combined oral contraceptives (COCs). Evidence mainly focuses on the type of progestogen used in COCs to establish the increased risk of VTE with less data assessed on the type of estrogen used. This meta-analysis aims to assess the risk of VTE associated with COCs containing synthetic estrogens like ethinylestradiol (EE) versus natural estrogens like estradiol (E2). Methods: A systematic review and meta-analysis was conducted following the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Literature searches were performed in December 2023 in MEDLINE and EMBASE to identify clinical studies comparing the VTE risk between COCs containing synthetic versus natural estrogens. Studies were selected through rigorous screening, and data extraction followed standardized protocols, with statistical analyses employing a random effects model. Results: The search yielded five relevant studies, involving over 560,000 women/time, demonstrating a significant 33% reduction in VTE risk among users of natural estrogen-based COCs compared to synthetic estrogen-based COCs (OR 0.67, 95% CI 0.51–0.87). Stratification analyses using adjusted hazard ratios (HR) of the main observationnal studies showed a 49% reduced VTE risk of E2-based pills compared to EE in association with levonorgestrel. Discussion and conclusion: Despite the longstanding use of EE-based COCs, emerging evidence supports a lower thrombotic risk associated with natural estrogens. This meta-analysis substantiates the lower VTE risk associated with natural estrogen-based COCs compared to synthetic alternatives, advocating for a re-evaluation of contraceptive guidelines to prioritize patient safety and reduce thrombotic risks. [ABSTRACT FROM AUTHOR]

Intravaginal rings (IVRs) represent a well-established, woman-controlled and sustained vaginal drug delivery system suitable for a wide range of applications. Here, we sought to investigate the differences in etonogestrel (ENG) and ethinyl estradiol (EE) release from a 3D-printed IVR utilizing continuous liquid interface production (CLIP™) (referred to as CLIPLOW for low drug loading and CLIPHIGH IVRs for high drug loading) and NuvaRing, a commercially available injection molded IVR. We conducted in vitro release studies in simulated vaginal fluid to compare the release of ENG and EE from CLIPLOW IVRs and NuvaRing. CLIPLOW IVRs had a similar hormone dose to NuvaRing and exhibited slightly slower ENG release and greater EE release in vitro compared to NuvaRing. When administered to female sheep, NuvaRing demonstrated greater ENG/EE levels in plasma, vaginal tissue and vaginal fluids compared to CLIPLOW IVR despite similar drug loadings. Leveraging observed hormones levels in sheep from NuvaRing as an effective contraceptive benchmark, we developed a long-acting CLIPHIGH IVR with increased ENG and EE doses that demonstrated systemic and local hormone levels greater than the NuvaRing for 90 days in sheep. No signs of toxicity were noted regarding general health, colposcopy, or histological analysis in sheep after CLIPHIGH IVR administration. Our results provided (1) a comparison of ENG and EE release between a 3D-printed IVR and NuvaRing in vitro and in vivo, (2) a preclinical pharmacokinetic benchmark for vaginally delivered ENG and EE and (3) the generation of a 90-day CLIP IVR that will be utilized in future work to support the development of a long-acting ENG/EE IVR combined with an antiretroviral for the prevention of HIV and unplanned pregnancy. [ABSTRACT FROM AUTHOR]

This bioequivalence research aims to evaluate the relative bioavailability and pharmacokinetic characteristics of ethinyl estradiol and drospirenone in the test preparation in comparison to the reference preparation during fasting conditions. A liquid chromatography method with tandem mass spectrometry was used to determine the concentrations of drospirenone and ethinyl estradiol in plasma. The pharmacokinetic parameters that were analyzed were the maximum plasma concentration (Cmax), time to achieve Cmax (tmax), elimination half life, and area under the concentration time curve of plasma (AUC0‐t, AUC0‐∞ for ethinyl estradiol, and AUC0‐72h for drospirenone). Both the AUC and Cmax parameters were determined to be between 80.00% and 125.00% (90% confidence intervals), which is the acceptable range. Based on the study findings, it was concluded that the test formulation, which includes 3 mg of drospirenone and 0.03 mg of ethinyl estradiol, demonstrated bioequivalence when compared to the reference formulation. [ABSTRACT FROM AUTHOR]

The endothelin A receptor antagonist zibotentan, combined with the sodium‐glucose co‐transporter‐2 inhibitor dapagliflozin, is being investigated for the treatment of chronic kidney disease with high proteinuria. To allow women of childbearing potential access to this treatment, highly effective contraception is required and drug interactions compromising contraception reliability must be avoided. This study investigated the risk of pharmacokinetic (PK) interaction between zibotentan and the contraceptives ethinyl estradiol and levonorgestrel. A single‐sequence, within‐participant comparison study was conducted in 24 healthy women of non‐childbearing potential, comparing the PK of ethinyl estradiol/levonorgestrel alone and with zibotentan. Single oral doses of 0.06 mg ethinyl estradiol/0.3 mg levonorgestrel were administered on Days 1 and 15; zibotentan 10 mg was dosed orally, once‐daily through Days 6–19. PK profiles were determined and ethinyl estradiol/levonorgestrel PK was compared between Day 1 and 15 based on geometric least‐squares mean ratios of PK parameters, including maximum observed concentration (Cmax) and area under the plasma concentration–time curve from zero to infinity (AUCinf). Co‐administration with zibotentan did not affect ethinyl estradiol PK (geometric mean ratio [90% confidence interval] Cmax 1.05 [0.99–1.11], AUCinf 1.00 [0.96–1.05]), while a weak interaction (increased exposure) was observed for levonorgestrel (Cmax 1.12 [1.02–1.23], AUCinf 1.30 [1.21–1.39]), which was regarded as without clinical relevance. Plasma exposure of ethinyl estradiol/levonorgestrel was not reduced by multiple‐dose zibotentan. In conclusion, contraception containing ethinyl estradiol/levonorgestrel is regarded possible under zibotentan‐containing treatments. This expands choices for women of childbearing potential, supporting diversity in the ZENITH High Proteinuria trial. [ABSTRACT FROM AUTHOR]

A novel ferrofluid prepared from a hydrophobic deep eutectic solvent (DES) and Fe3O4@graphite composite materials was introduced as a green microextraction medium for the separation and enrichment of trace estrogens in real samples. It was found that the ferrofluid greatly improved the capacity and selectivity of target analytes, benefiting from the enrichment of both DES and Fe3O4@graphite composite materials. Using a combination of high-performance liquid chromatography–fluorescence detection (HPLC-FLD) and vortex-assisted liquid–liquid microextraction (VALLME), a new method was established for simultaneous rapid processing and accurate determination of three estrogens (estradiol [E2], estriol [E3], and ethinyl estradiol [EE2]) in environmental water and urine samples. Key parameters affecting the extraction efficiency were optimized using a single-factor approach and response surface methodology. Under optimal conditions, this method yielded a low limit of detection (1.01 ng L−1, 3.03 ng L−1, and 25.0 ng L−1 for EE2, E2, and E3, respectively), wide linear range (3–200,000 ng L−1), high enrichment factors (9.81–47.2), and satisfactory recovery (73.8–129.0%). Compared with traditional analytical techniques, this method avoids the use of volatile toxic organic extraction solvents and cumbersome phase separation operations. [ABSTRACT FROM AUTHOR]

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Oral contraceptive pills, of all types, are used by approximately 151 million women worldwide; however, a clear understanding of the concentrations of endogenous and exogenous hormones across a 28-day combination monophasic oral contraceptive pill pack is not well described. In our study of 14 female participants taking various combination monophasic oral contraceptive pills, we found significant fluctuations in endogenous and exogenous hormone levels throughout the pill cycle. Our analysis revealed significantly greater levels of ethinyl estradiol on the 20th and 21st days of active pill ingestion, compared with days 1-2 (active) and days 27-28 (inactive pill ingestion). Conversely, estradiol concentrations decreased during active pill consumption, while progestin and progesterone levels remained stable. During the 7 days of inactive pill ingestion, estradiol levels rose sharply and were significantly higher at days 27-28 compared with the mid and late active phase time points, while ethinyl estradiol declined and progestin did not change. These findings challenge the previous assumption that endogenous and exogenous hormones are stable throughout the 28-day pill cycle. NEW & NOTEWORTHY The results from this study have wide-ranging implications for research and treatment in women’s health including considerations in research design and interpretation for studies including women taking oral contraceptives, the potential for more precise and personalized methods of dosing to reduce unwanted side effects and adverse events, and the potential treatment of a variety of disorders ranging from musculoskeletal to neurological with exogenous hormones. [ABSTRACT FROM AUTHOR]

Context Adolescents and young women (AYA) with type 1 diabetes (T1D) may require hormonal contraception for an extended period. However, it is unclear what effect hormonal contraception has on telomere length, a marker of the risk for complications. Objective To investigate the relative telomere length (RTL) in AYA with T1D (AYA-T1D) and healthy young women (AYA-C) after 18 months of combined oral contraception use (COC) with ethinyl estradiol/desogestrel, or a subdermal etonogestrel implant (IM). Methods A nonrandomized prospective study was performed in which 39 AYA-T1D and 40 AYA-C chose the COC or the IM. RTL was measured by monochrome multiplex–quantitative PCR in DNA from peripheral blood mononuclear cells (PBMC). The impact of contraceptives and clinical variables on RTL was assessed using lineal regression analysis. Results Longer RTL compared to baseline was observed in AYA-T1D (P <.05) and AYA-C (P <.01) after using the IM. However, the total of AYA and the AYA-C group treated with COC decreased RTL after 18 months of treatment compared to baseline (P <.05). The type of contraceptive used was determinant for the changes in RTL compared to baseline in all subjects and controls (P ≤. 006). For AYA-T1D, HbA1c levels were not associated with RTL, but the high-sensitivity C-reactive protein was negatively related with the changes in RTL at 18 months compared to baseline (standardized R2 : 0.230, P =.003). Conclusion IM was associated with longer RTL in AYA-T1D and AYA-C. In contrast, a shortening of telomere length in PBMC was observed after using COC. [ABSTRACT FROM AUTHOR]

We compared the efficacy of 4 mg drospirenone (DRSP) progestin-only pills (POPs) versus combined oral contraceptive pills (COCs) containing 0.02 mg of ethinyl estradiol (EE) and 0.075 mg of gestodene (GS) in ovulation inhibition and inducing unfavorable cervical mucus changes using a delayed-starting approach. This randomized controlled trial involved 36 participants aged 18–45 years. The major outcomes included ovulation inhibition assessed using the Hoogland and Skouby score, and cervical mucus permeability, assessed using the modified World Health Organization score. The results demonstrated ovulation inhibition rates of 77.8% for the EE/GS group and 88.9% for the DRSP group. The risk ratio and absolute risk reduction were 0.50 (95% confidence interval [CI]: 0.10, 2.40) and − 0.11 (95% CI: − 0.35, 0.13), respectively, satisfying the 20% non-inferiority margin threshold. The median time to achieve unfavorable cervical mucus changes was comparable between the DRSP (3 days, interquartile range [IQR]: 6 days) and EE/GS (3.5 days, IQR: 4 days) groups. However, the DRSP group had a higher incidence of unscheduled vaginal bleeding (55.56% vs. 11.11%; p = 0.005). DRSP-only pills, initiated on days 7–9 of the menstrual cycle, were non-inferior to EE/GS pills in ovulation inhibition. However, they exhibited delayed unfavorable cervical mucus changes compared to the standard two-day backup recommendation. Clinical trial registration: Thai Clinical Trials Registry (TCTR20220819001) https://www.thaiclinicaltrials.org/show/TCTR20220819001. [ABSTRACT FROM AUTHOR]

In avian embryos, xenoestrogens induce abnormalities in reproductive organs, particularly the testes and Müllerian ducts (MDs). However, the molecular mechanisms remain poorly understood. We investigated the effects of ethynylestradiol (EE2) exposure on gene expression associated with reproductive organ development in Japanese quail embryos. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) analysis revealed that the left testis containing ovary-like tissues following EE2 exposure highly expressed the genes for steroidogenic enzymes (P450scc , P45017α, lyase , and 3β-HS D) and estrogen receptor-β, compared to the right testis. No asymmetry was found in these gene expression without EE2. EE2 induced hypertrophy in female MDs and suppressed atrophy in male MDs on both sides. RNA sequencing analysis of female MDs showed 1,366 differentially expressed genes between developing left MD and atrophied right MD in the absence of EE2, and these genes were enriched in Gene Ontology terms related to organogenesis, including cell proliferation, migration and differentiation, and angiogenesis. However, EE2 reduced asymmetrically expressed genes to 21. RT-qPCR analysis indicated that genes promoting cell cycle progression and oncogenesis were more highly expressed in the left MD than in the right MD, but EE2 eliminated such asymmetric gene expression by increasing levels on the right side. EE2-exposed males showed overexpression of these genes in both MDs. This study reveals part of the molecular basis of xenoestrogen-induced abnormalities in avian reproductive organs, where EE2 may partly feminize gene expression in the left testis, developing as the ovotestis, and induce bilateral MD malformation by canceling asymmetric gene expression underlying MD development. [ABSTRACT FROM AUTHOR]

Aims: The current work describes the development of mechanistic vaginal absorption and metabolism model within Simcyp Simulator to predict systemic concentrations following vaginal application of ring and gel formulations. Methods: Vaginal and cervix physiology parameters were incorporated in the model development. The study highlights the model assumptions including simulation results comparing systemic concentrations of 5 different compounds, namely, dapivirine, tenofovir, lidocaine, ethinylestradiol and etonogestrel, administered as vaginal ring or gel. Due to lack of data, the vaginal absorption parameters were calculated based on assumptions or optimized. The model uses release rate/in vitro release profiles with formulation characteristics to predict drug mass transfer across vaginal tissue into the systemic circulation. Results: For lidocaine and tenofovir vaginal gel, the predicted to observed AUC0‐t and Cmax ratios were well within 2‐fold error limits. The average fold error (AFE) and absolute AFE indicating bias and precision of predictions range from 0.62 to 1.61. For dapivirine, the pharmacokinetic parameters are under and overpredicted in some studies due to lack of formulation composition details and relevance of release rate used in ring model. The predicted to observed AUC0‐t and Cmax ratios were well within 2‐fold error limits for etonogestrel and ethinylestradiol vaginal ring (AFEs and absolute AFEs from 0.84 to 1.83). Conclusion: The current study provides first of its kind physiologically based pharmacokinetic framework integrating physiology, population and formulation data to carry out in silico mechanistic vaginal absorption studies, with the potential for virtual bioequivalence assessment in the future. [ABSTRACT FROM AUTHOR]

The oestrogenic component of combined oral contraceptives (COCs) has changed over years with the aim of reducing oestrogen-related side effects and risks, whilst maintaining oestrogen beneficial effects, particularly on cycle control. To describe the pharmacological profiles of different oestrogens commonly used in COCs to provide insights on contraceptive prescription tailored to women's needs. All COCs ensure a high contraceptive efficacy. COCs containing the natural oestrogens oestradiol (E2), oestradiol valerate (E2V) and estetrol (E4) have limited impact on liver metabolism, lipid and carbohydrate metabolism, haemostasis and sex hormone binding globulin levels, compared with ethinylestradiol (EE). COCs with E2 and E2V appear also to entail a lower elevation of the risk of venous thromboembolism vs. EE-containing pills. No epidemiological data are available for E4-COC. E2- and E2V-containing COCs seem to exert a less stabilising oestrogenic effect on the endometrium compared with EE-COCs. The E4-COC results in a predictable bleeding pattern with a high rate of scheduled bleeding and minimal unscheduled bleeding per cycle. Based on in vitro and in vivo animal data, E4 seems to be associated with a lower effect on cell breast proliferation. Today various COCs contain different oestrogens. Prescribers must be familiar with the different properties of each oestrogen for a tailored contraceptive recommendation, considering their safety and contraceptive efficacy, as well as women's needs and preferences. For contraceptive pills physicians can choose among different oestrogens, besides many progestins. Natural oestrogens have less metabolic impact vs EE, while EE and E4 seem to provide a better cycle control. Knowing the different oestrogen characteristics is crucial for adjusting pill prescription to women's needs and desires. [ABSTRACT FROM AUTHOR]