This study aimed to determine whether the use of vaginal Endometrin plus intramuscular progesterone on every third day (VIM) in programmed frozen embryo transfer (FET) is associated with lower pregnancy and live birth rates compared to daily intramuscular progesterone (IM). FET data from a single program were collected between November 2018 and December 2021. A total of 903 FETs were analyzed, including 504 FETs in the IM group, and 399 FETs in the VIM group. Inclusion criteria were women undergoing FETs with either 50 mg daily IM progesterone only (control) or 200 mg Endometrin twice daily plus 50 mg IM progesterone on every third day, with the transfer of a single day 5 or 6 frozen embryo. There were no significant differences in patient age at time of FETs, BMI, endometrial thickness, blastocyst quality, or infertility diagnosis between the groups. The VIM had significantly lower positive hCG and clinical pregnancy rates compared to the IM (60.2% vs 72.0% and 40.6% vs 56.7%, respectively, P = 0.0002 and P < 0.0001). The live birth rate was 36.1% in the VIM, compared to 49.4% in the IM (P < 0.0001). These findings also remained significant when excluding FETs with donor egg (35.9% vs 50.1%, P < 0.0001). This study demonstrated that VIM in FET cycles yields significantly lower pregnancy and live birth rates compared to IM along. IM progesterone alone may be preferable to combined Endometrin and IM progesterone in patients undergoing programmed frozen embryo transfers.

BACKGROUND: To describe and conclude the in vitro fertilization (IVF) results of patients with X chromosome abnormality.
METHODS: A retrospective case series was conducted. According to the number of normal X, patients were allocated into two groups: Group A (patients with only a normal X, while other X has any types of abnormalities) and Group B (patients have two or more normal X chromosomes). Clinical data, including basic information, fertility information, and IVF outcomes, were collected.
RESULTS: Fourteen patients with X chromosome abnormality were included, among which 13 patients underwent a total of 29 cycles. Patients in Group B had five successful pregnancies and three live births, while no patient in Group A had a clinical pregnancy. Furthermore, the blastocyst formation rate and incidence of pregnancy were significantly lower in Group A (Z = -3.135, p = .002; Z = -2.946, p = .003, respectively). When controlled covariates, the karyotype of one normal X was also a risk factor for both blastocyst formation rate and success pregnancy (β = .820, 95% confidence interval [CI] = 0.458-1.116, β = .333, 95% CI = 0.017-0.494, respectively).
CONCLUSIONS: Our results revealed that women with only one normal X might suffer from worse IVF outcomes, mainly blastocyst formation rate, compared with those who had two or more normal X, including mosaic Turner syndrome and 47,XXX.

OBJECTIVE: Failure to collect oocytes at the time of oocyte pick-up is an unfavorable outcome of in vitro fertilization (IVF) cycles. In these cases, prompt intrauterine insemination (IUI) could be an option (rescue IUI), but this possibility has been poorly studied.
METHODS: Rescue IUI is routinely offered in our unit in women failing to retrieve oocytes, provided that they have at least one patent tube, normal male semen analysis, and the total number of developed follicles is ≤ 3. We therefore reviewed all oocyte retrievals performed from 2006 to 2022 in our unit to identify these cases. As a comparator, we referred to preplanned IUI performed during the same study period. The 95% confidence interval (95% CI) of proportions was calculated using a binomial distribution model.
RESULTS: Rescue IUI was performed in 96 out of 3531 oocyte retrievals (2.7%; 95% CI 2.2-3.3%). Six live births were obtained, corresponding to 6.2% (95% CI 2.3-13.1). All pregnancies were singletons.
CONCLUSIONS: Rescue IUI in women failing to retrieve oocytes is a possible option that may be considered in selected cases. The efficacy is low, but the procedure is simple, and without significant risks. Generalizability to a conventional IVF protocol setting is however limited.

BACKGROUND: Polycystic ovary syndrome (PCOS) is the most common reproductive endocrine disorder among women of childbearing age and is the primary cause of anovulatory infertility, accounting for 70% to 80% of cases. Ovulation induction is the main treatment approach for infertile patients with PCOS. Commonly utilized medications for this purpose are clomiphene citrate (CC) and letrozole (LE). Clomiphene citrate administration results in an ovulation rate ranging from 60% to 85%, while the pregnancy rate is limited to 35% to 40%, and a further reduction is observed in live birth rates. Letrozole demonstrates a slightly higher pregnancy rate and live birth rate compared to clomiphene citrate, although challenges persist in terms of longer stimulation cycles, multiple pregnancies, and the risk of ovarian hyperstimulation syndrome (OHSS). Clinical reports indicate that acupuncture therapy shows promising efficacy in treating patients with PCOS-related infertility, despite a partially unclear understanding of its underlying mechanisms.
METHODS: In this study, one patient did not achieve pregnancy despite more than a year of ovulation induction using clomiphene citrate and letrozole. However, after 3 months of receiving cheek acupuncture therapy, she successfully conceived and gave birth to a liveborn baby. Another patient achieved natural conception and live birth after 2 months of exclusive cheek acupuncture therapy.
METHODS: PCOS.
METHODS: Cheek acupuncture therapy.
RESULTS: Both of them successfully conceived and gave birth to a liveborn baby.
CONCLUSIONS: These findings suggest that cheek acupuncture therapy can effectively stimulate follicle development and ovulation, potentially improving endometrial receptivity. According to holographic theory, there is a biologically holographic model within the cheek region that shares a homology with the human body structure. This model provides an explanation for the regulatory effects of cheek acupuncture point stimulation on the Hypothalamic-Pituitary-Ovarian axis (HPO), which subsequently influences follicle development and ovulation in patients. Consequently, when cheek acupuncture therapy is applied alone or in combination with ovulation induction medication, patients have the ability to achieve successful pregnancy and experience a smooth delivery.

OBJECTIVE: Is ovarian stimulation with levonorgestrel intrauterine system (LNG-IUS) in situ and co-treatment with letrozole safe and effective in patients undergoing fertility-sparing combined treatment for atypical endometrial hyperplasia (AEH) or early endometrial cancer limited to the endometrium?
METHODS: Retrospective case-control study recruiting women who had undergone fertility-sparing \'combined\' treatment and ovarian stimulation with letrozole and LNG-IUS in situ. The \'three steps\' hysteroscopic technique was used. Once complete response was achieved, the ovaries were stimulated, and mature oocytes cryopreserved. The LNG-IUS was removed, and embryos transferred. A comparative analysis was conducted between the two control groups of the initial outcomes of ART (number of oocytes and MII oocytes retrieved): healthy infertile women undergoing ovarian stimulation for IVF/ICSI (control group A); and patients diagnosed with breast cancer who underwent ovarian stimulation with letrozole (control group B).
RESULTS: Of the 75 patients analysed, 15 underwent oocyte cryopreservation after achieving a complete response to fertility-sparing treatment (study group); 30 patients in control group A and B, respectively. No statistically significant differences were observed in retrieved oocytes and mature oocytes between the study and control groups. In the nine patients who underwent embryo transfer, clinical pregnancy (55.6%), cumulative live birth (44.4%) and miscarriage (20%) rates were reported. In three patients with AEH, recurrence occurred (12%) at 3, 6 and 16 months after removing the LNG-IUS to attempt embryo transfer, respectively.
CONCLUSIONS: Fertility-sparing hysteroscopic combined treatment and subsequent ovarian stimulation with letrozole and LNG-IUS in situ could be suggested to women with AEH or early endometrial cancer who ask for future fertility preservation.

BACKGROUND: The success of pregnancy depends on various factors, with the endometrial receptivity being a crucial component. Endometrial thickness (EMT) serves as a direct indicator for assessing endometrial receptivity. Previous studies have suggested that a thin endometrium is associated with lower pregnancy rates, especially in patients with an EMT of less than 4 mm. Even in assisted reproductive technology cycles with high success rates, clinical pregnancy cases in patients with such thin endometrium are reported to be very few, let alone in natural conception cycles. Therefore, a thin endometrium poses significant challenges for infertility patients. In this study, patients with an extremely thin endometrium were able to achieve clinical pregnancy and successful live births through natural conception, highlighting the possibility of success even in challenging cases.
METHODS: The patient presented with polycystic ovary syndrome and ovulation disorders. She underwent a natural cycle of letrozole-induced ovulation. On the day of the human chorionic gonadotropin trigger, she had an EMT of 3.8 mm.
METHODS: Polycystic ovary syndrome, ovulation disorders, thin endometrium.
METHODS: The patient received medications including Progynova, Aspirin, and Dydrogesterone.
RESULTS: The patient achieved spontaneous conception and subsequently had a live birth.
CONCLUSIONS: This case report underscores the significance of managing a thin endometrium during letrozole-induced ovulation. While EMT is traditionally pivotal for predicting embryo implantation success, our findings indicate that endometrial receptivity extends beyond thickness alone. Factors such as endometrial morphology, type, and blood supply play crucial roles. Successful pregnancies with a 3.8 mm EMT are rare, making this case a beacon of hope for such patients. It highlights that, with appropriate interventions, successful pregnancies remain attainable. For those with a thin endometrium, emphasis should extend beyond thickness, addressing ways to enhance both endometrial blood supply and morphology for improved pregnancy rates.

BACKGROUND: Interstitial pregnancy may still happen even after ipsilateral salpingectomy, resulting in massive hemorrhage. Therefore, the purpose of the study is to identify risk factors associated with interstitial pregnancy following ipsilateral salpingectomy and discuss possible prevention.
METHODS: We conducted a retrospective cohort study in a single, large, university-affiliated hospital. Data of 29 patients diagnosed with interstitial pregnancy following ipsilateral salpingectomy from January 2011 to November 2020 were assigned into the case group (IP group). Whereas there were 6151 patients with intrauterine pregnancy after unilateral salpingectomy in the same period. A sample size of 87 control patients was calculated to achieve statistical power (99.9%) and an α of 0.05. The age, BMI and previous salpingectomy side between the two group were adjusted with PSM at a ratio of 1:3. After PSM, 87 intrauterine pregnancy patients were successfully matched to 29 IP patients.
RESULTS: After PSM, parous women were more common and intrauterine operation was more frequent in the IP group compared with control group (P<0.05). There was only one patient undergoing IVF-ET in the IP group as compared with 29 cases in the control group (3.4% vs. 33.3%, P<0.05). Salpingectomy was performed on 5 patients in the IP group and 4 patients in the control group due to hydrosalpinx (P<0.05). Logistic regression indicated that hydrosalpinx was the high risk factor of interstitial pregnancy following ipsilateral salpingectomy (OR = 8.175).
CONCLUSIONS: Hydrosalpinx appears to be an independent factor contributing to interstitial pregnancy following ipsilateral salpingectomy in subsequent pregnancy.

OBJECTIVE: Is endometriosis detrimental to embryo implantation?
METHODS: A retrospective matched case-control study of women with a surgical or ultrasound diagnosis of endometriosis at Fondazione IRCCS Ca\'Granda Ospedale Maggiore Policlinico di Milano between 2015 and 2021. Women with endometriosis who underwent a \'freeze-all\' cycle during an IVF treatment were eligible to be included. They were matched to patients without the disease, who also underwent cryopreserved blastocyst transfer cycles, in a 1:1 ratio by age (±1 year), and number (=) and quality (±1 top versus low) of cryopreserved blastocysts. All women underwent single frozen embryo transfer, and assisted reproductive technology outcomes suggested by the Core Outcome Measure for Infertility Trials initiative were evaluated. The main outcome was the cumulative live birth rate per cycle.
RESULTS: One hundred and one women with endometriosis and 101 matched unaffected women were included. Cumulative live birth rate per cycle did not vary between women with and without endometriosis (50% versus 58%, respectively; P = 0.32). On the basis of the Kaplan-Meier analysis, the predicted success rates over four embryos transferred were also similar (74% versus 82%, respectively; P = 0.67).
CONCLUSIONS: In women with moderate or severe endometriosis, these retrospective results seem to indicate no or a limited effect of the disease on endometrial receptivity.

Superfetation is a very rare occurrence. In the context of assisted reproduction, it has been reported only as an intrauterine pregnancy after ovarian stimulation and/or embryo transfer in the presence of an undiagnosed ectopic pregnancy. Here we report a case of a 27-year-old anovulatory patient, gravida 1 para 1, who underwent two frozen-thawed single-blastocyst transfers in separate cycles. The patient reported that 12 days after the first transfer, she had menstrual bleeding and stopped her estradiol and progesterone supplementation without undergoing a blood human chorionic gonadotropin (βhCG) test. At her request, a second cycle was immediately initiated, with endometrial thickness measuring 4 mm. Eleven days after the second transfer, the βhCG value was inappropriately high. A right tubal pregnancy corresponding to 8 gestational weeks was diagnosed. Laparoscopy revealed a prominent right tubal pregnancy in addition to a significantly smaller left tubal pregnancy. The discordant tubal pregnancies were confirmed histologically. To our knowledge, superfetation involving a second ectopic pregnancy coexistent with a first, contralateral ectopic pregnancy consequent to consecutive in vitro fertilization procedures has not previously been described in the medical literature. This case emphasizes the importance of routine βhCG testing after every IVF cycle, even if apparently unsuccessful.

OBJECTIVE: To evaluate self-reported survey data provided by US oocyte donors on their experiences with ovarian hyperstimulation syndrome and possible correlations between OHSS severity and number of oocytes retrieved, trigger type, and prior OHSS history.
METHODS: An 85-question retrospective survey was administered online. Survey questions included demographic information, reasons for donating, immediate per-cycle experiences and outcomes, perceptions of informed consent, and perceived impact of donation on long-term health. Quantitative Data for this study was collected between February 2019 and September 2020 via QualtricsXM (January 2019), an online survey platform. Follow-up interviews were also conducted. Participants were recruited via fertility clinics, egg donation agencies, and online forum. The research was approved by the University of California, San Francisco Institutional Review Board (#14-14765).
RESULTS: Of 420 initiated US oocyte donor online surveys, 289 (68%) respondents provided detailed information on per cycle experiences with ovarian hyperstimulation syndrome, number of oocytes retrieved, and trigger type over a total of 801 cycles. On cycles where donors reported receiving GnRH agonist triggers (n = 337), they reported milder OHSS compared to cycles with hCG or dual triggers. Among donors undergoing multiple retrieval cycles, the severity of OHSS in second cycles was strongly associated with OHSS severity in first cycles.
CONCLUSIONS: Self-reported OHSS in oocyte donors is lower in GnRH antagonist stimulation protocols combined with GnRHa trigger and in cycles where donors reported fewer than 30 oocytes retrieved. Donors who reported severe OHSS on a prior cycle were significantly more likely to experience severe OHSS on a subsequent cycle.