Tamoxifen has played a vital role in endocrine therapy for the treatment of estrogen receptor-positive breast cancer. We examined the effect of tamoxifen in patients with a thin endometrium in frozen-thawed embryo transfer (FET) cycles and compared the improvement in endometrial thickness (EMT) and pregnancy outcomes stratified by different etiologies of thin endometrium. A total of 226 women were recruited for a new tamoxifen protocol; all had an EMT of less than 7.5 mm in previous cycles, including natural cycle (NC), hormone replacement treatment (HRT), and ovulation induction (OI) cycles. Compared with previous cycles, tamoxifen cycles showed a significantly increased EMT (from 6.11 ± 0.98 mm to 7.87 ± 1.48 mm in the NC group, from 6.24 ± 1.01 mm to 8.22 ± 1.67 mm in the HRT group, and from 6.34 ± 1.03 mm to 8.05 ± 1.58 mm in the OI group; all P < .001). Patients were further divided into 3 groups based on the causes of their thin endometrium: (1) history of intrauterine adhesion (n = 34), (2) history of uterine curettage (n = 141), and (3) polycystic ovary syndrome (PCOS; n = 51). Patients with PCOS obtained the thickest EMT (9.31 ± 1.55 mm), the lowest cycle cancellation rate (11.76%), and the highest rate of clinical pregnancy (60%) and live birth (55.56%) per transfer ( P < .001). Multivariable regression analysis showed that EMT was related to live birth (odds ratio: 1.487; 95% confidence interval: 1.172-1.887). A tamoxifen protocol improves EMT in patients after NC, HRT, and OI cycles during FET. Patients with PCOS show the most benefit from tamoxifen and achieve better pregnancy outcomes.
PMID 28345485 28345485 DOI 10.1177/1933719117698580 10.1177/1933719117698580
Cite this article
Ke, H., Jiang, J., Xia, M., Tang, R., Qin, Y., & Chen, Z. (2018). The Effect of Tamoxifen on Thin Endometrium in Patients Undergoing Frozen-Thawed Embryo Transfer. Reproductive sciences (Thousand Oaks, Calif.), 25(6), 861-866. https://doi.org/10.1177/1933719117698580
Ke H, Jiang J, Xia M, Tang R, Qin Y, Chen Z. The Effect of Tamoxifen on Thin Endometrium in Patients Undergoing Frozen-Thawed Embryo Transfer. Reprod Sci. 2018;25(6):861-866. doi:10.1177/1933719117698580
Ke, Hanni, et al. "The Effect of Tamoxifen on Thin Endometrium in Patients Undergoing Frozen-Thawed Embryo Transfer." Reproductive sciences (Thousand Oaks, Calif.), vol. 25, no. 6, 2018, pp. 861-866.
Keywords
Estrogen Antagonists, Tamoxifen
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Mørch NF et al., 2026·Human reproduction (Oxford, England)
Are maternal concentrations of pregnancy-associated plasma protein-A (PAPP-A) and insulin-like growth factor-1 (IGF-1) influenced by the frozen embryo transfer (FET) protocol in early pregnancy? Maternal concentrations of PAPP-A and IGF-1 were significantly lower in programmed cycle (PC) FET compared to modified natural cycle (mNC) FET among ovulatory women and compared to gonadotrophin-stimulated cycle (gSC) FET in anovulatory women. PC-FET has been associated with increased risks of preeclampsia and other placenta-related complications, pointing to altered placental development. PAPP-A and IGF-1 are biochemical markers of early placental function, and reduced levels have been linked to preeclampsia and other adverse outcomes. These markers may therefore provide insight into the pathways underlying the distinct risk profile of PC-FET. STUDY DESIGN, SIZE, This is a secondary analysis from a randomized controlled trial investigating estradiol and progesterone concentrations in FET treatments. The trial was conducted at Copenhagen University Hospital-Herlev, Denmark, from April 2021 to December 2024. Biochemical analyses for PAPP-A and IGF-1 were performed on stored biobank samples from the trial. The main analyses included women with ongoing pregnancies (n = 116), while additional analyses of IGF-1 were conducted in all ovulatory women with available biobank samples (n = 193). PARTICIPANTS/MATERIALS, SETTING, Eligible participants were women aged 18-40 years with BMI ≤35 kg/m2 undergoing frozen-thawed autologous blastocyst transfer. Ovulatory women were randomized to mNC or PC, and anovulatory women to gSC or PC. Samples were collected at the following 7 timepoints on the 2nd or 3rd day of menstrual bleeding, on the day of trigger/endometrial thickness ≥7 mm, on the day of embryo transfer and by gestational ages (GA) 4 + 2, 6 + 0, 8 + 0, and 9 + 6. Data on placental weight were collected at delivery. MAIN The present analyses included women with ongoing pregnancies 43 in the ovulatory mNC group, 42 in the ovulatory PC group, 16 in the anovulatory gSC group, and 15 in the anovulatory PC group. PC had substantially lower IGF-1 concentrations from treatment initiation through GA 8 + 0 compared to both mNC and gSC. Ovulatory women treated with PC showed significantly lower PAPP-A concentrations during endometrial preparation (7.4 vs 8.7 mU/l; adjusted P = 0.02), at embryo transfer (6.7 vs 8.8 mU/l; adjusted P < 0.001), and GA 4 + 2 (7.2 vs 8.5 mU/l; adjusted P = 0.03) than women treated with mNC. Among anovulatory women, PAPP-A concentrations were also reduced during endometrial preparation (5.8 vs 9.1 mU/l; adjusted P = 0.008) in PC compared to gSC. LIMITATIONS, As this was a secondary analysis, no formal power calculation was made, and statistical power may therefore be limited. We provide evidence that PC-FET was followed by lower IGF-1 concentrations in early pregnancy and by time-dependent reductions in PAPP-A compared to mNC-FET and gSC-FET. These findings suggest alterations in early placental biology that may contribute to the adverse obstetric risk profile associated with PC-FET. Future studies should clarify whether these changes are related to the use of oral estradiol and whether alternative administration routes could modify this risk. STUDY FUNDING/COMPETING INTEREST(S): The trial was funded by Gedeon Richter Nordics AB, including analysis of biobank samples (grant numbers DK-2019-04, DK-2022-03, DK-2023-08, DK-2023-06, DK-2024-08). The trial also received one grant from the Gangsted-Rasmussen Foundation (grant number A39784) and a grant was obtained from the local research board at Copenhagen University Hospital-Herlev. The study was designed and planned independently, with no involvement from the funders in data analysis or interpretation of the results. N.F.M. has received funding for congress attendance from Gedeon Richter Nordics AB and Merck A/S, unrelated to the present work. B.N. has received grants to the institution from Merck A/S, Gedeon Richter Nordics AB, and Ferring Pharmaceuticals A/S, along with personal fees from Ferring Pharmaceuticals A/S, travel support from Gedeon Richter Nordics AB, and has participated in a data safety monitoring or advisory board for Ferring Pharmaceuticals A/S, outside of this research. M.K. has received funding from Rigshospitalets Research Board outside of this research. L.R. has received a research grant from the Novo Nordisk Foundation outside of this research. P.F.S. has received grants from Merck A/S, Gedeon Richter Nordics AB, and Ferring Pharmaceuticals A/S, travel support from Ferring Pharmaceuticals A/S, and personal fees from Novo Nordisk for webinars, outside of this study. 2020-001218-39 in EudraCT.
InfertilityIVF Outcomes and StatisticsFrozen Embryo TransferPopulation-Level Data
Human Fertilisation and Embryology Authority, 2025
# Fertility treatment 2023: Preliminary UK statistics for IVF and DI treatment, storage, Published: June 2025
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[Download the underlying dataset as Excel Worksheet](https://www.hfea.gov.uk/media/3qip3kon/fertility-treatment-2023-trends-and-figures-underlying-dataset.xlsx "Download the underlying dataset for the ‘Fertility treatment 2023: trends and figures’ report")
## - [Main points](https://www.hfea.gov.uk/about-us/publications/research-and-data/fertility-treatment-2023-trends-and-figures/#main-points)
- [Note on preliminary data](https://www.hfea.gov.uk/about-us/publications/research-and-data/fertility-treatment-2023-trends-and-figures/#note-on-preliminary-data)
- [Section 1: More babies born from IVF in the UK](https://www.hfea.gov.uk/about-us/publications/research-and-data/fertility-treatment-2023-trends-and-figures/#section-1)
- [Section 2: IVF pregnancy and birth rates using fresh embryo transfers increased over the years, though lower for Black patients](https://www.hfea.gov.uk/about-us/publications/research-and-data/fertility-treatment-2023-trends-and-figures/#section-2)
- [Section 3: Average pregnancy and birth rates using frozen embryo transfers increased in 2023](https://www.hfea.gov.uk/about-us/publications/research-and-data/fertility-treatment-2023-trends-and-figures/#section-3)
- [Section 4: Multiple births rate from IVF is one of the lowest in the world](https://www.hfea.gov.uk/about-us/publications/research-and-data/fertility-treatment-2023-trends-and-figures/#section-4)
- [Section 5: Most treatment types have increased across the UK since 2019](https://www.hfea.gov.uk/about-us/publications/research-and-data/fertili...
Endocrine disorders negatively influence the ovarian function, and increasing incidence of endocrine diseases with age may have further negative effects on pregnancy rate. Prospective cohort study of 231 consecutively enrolled patients underwent IVF treatment. In patients with known endocrine disorders, the laboratory parameters were corrected before IVF treatment. One hundred sixty one patients (69.7%) had at least one known and treated endocrine disorder (study group), and 70 patients were endocrine negative (control group). Endocrine disorders diagnosed were thyroid disorders (32.5%), diminished ovarian reserve (23.8%), insulin resistance (22.5%), PCOS (15.2%), hyperprolactinaemia (13.4%), obesity (12.1%), hypogonadotropic hypogonadism (0.8%) and congenital adrenal hyperplasia (0.2%). Before the IVF treatment, systematic endocrine laboratory examinations were performed in all patients. Higher age, BMI and FSH were found in the study group, while AMH level was lower. There were no differences in LH, E2, prolactin, TSH, FT3, FT4, TT, DHEAS, androstendione, 17-OHP and SHBG level between the study and control groups. The study group had higher baseline glucose, baseline insulin, 120-min glucose and 120-min insulin level after oral glucose tolerance test. With no difference in the IVF cycles performed, pregnancy rate was lower in the study group (61.43% vs. 34.16%; p = 0.003), and this difference (p = 0.0151) remained in age-corrected rates, as well. The analyses were also performed in individual endocrinology groups. The prevalence of endocrine disorders is high in females participating in IVF programs, and they are often accompanying each other. Even after proper correction, the presence of the endocrine disorder negatively influences the pregnancy rate in IVF treatment.
Brodeur TY et al., 2022·Reproductive sciences (Thousand Oaks, Calif.)
Infertility has a prevalence of up to 16% worldwide and is on the rise in developed nations, largely due to pursuing childbearing at advanced reproductive ages. Advances in assisted reproductive technology have benefitted socioeconomically advantaged patients disproportionately. High costs of fertility care are largely responsible for this disparity; however, patients in rural areas also face barriers in accessing both gynecology and reproductive endocrinology subspecialty care. Here, focusing on the USA, we discuss fertility care in geographically underserved areas and low-resource settings, and the impact on reproductive outcomes. Increased innovation to improve patient access to fertility care such as assisted reproductive technology is critical for ensuring equity. Remote monitoring is frequently performed by fertility centers, but partnership with local gynecologists has also been demonstrated to be an effective assisted reproductive technology monitoring method. Telehealth is now in mainstream use and the continued application to reduce geographic barriers to infertility patients is imperative. Partnership between local gynecologists and reproductive endocrinology and infertility specialists may improve patient access to fertility care and provide the unique benefits of continuity and ongoing local social support.