Publications by authors named "Raymond H W Li"
Background: This study aims to investigate the association of pre-conception vitamin D levels on adverse pregnancy outcomes in women undergoing in vitro fertilization with fresh embryo transfer.
Methods: This was a retrospective cohort study using archived serum 25-hydroxyvitamin D measured in the pre-conception period before ovarian stimulation in patients undergoing in vitro fertilization with fresh autologous embryo transfer. A total of 306 women were included and adverse pregnancy outcomes in their resulting pregnancy were recorded.
Purpose: To assess the association of serum vitamin D level and the live birth rate in women undergoing frozen embryo transfer (FET).
Methods: This is a retrospective cohort study involving 1489 infertile women who had frozen embryo transfer at two tertiary reproductive medicine centres from 2019 to 2021. Only the first frozen embryo transfer was included for women who had repeated transfers during the period.
Article Synopsis
- Levonorgestrel (LNG) is primarily used as an emergency contraceptive by delaying ovulation, and this study aimed to explore its effects on the human Fallopian tube's ciliary movement and muscle contractions.
- In an experimental setup using tissue samples from women, the researchers tested LNG at various concentrations to see any changes in ciliary beat frequency and muscular contractions.
- Results showed that while LNG did not significantly affect ciliary movement or muscle tone, the highest concentration (100 ng/ml) did reduce muscular contractions, indicating that the Fallopian tube is not likely a target for LNG's contraceptive effects at typical emergency contraception doses.
Article Synopsis
- * This review summarizes what is currently known about B cell functions during pregnancy, highlighting different B cell types and their influences on pregnancy outcomes.
- * It also discusses the impact of B cell-related autoantibodies, cytokines, and signaling pathways on complications like pregnancy loss, preeclampsia, and preterm birth.
Article Synopsis
- The World Health Organization lists oral emergency contraception (EC) as an essential medicine, with ulipristal acetate (UPA) and levonorgestrel (LNG) being the recommended options.
- UPA is more effective than LNG, and both work by delaying ovulation, although they don't prevent implantation in the uterus.
- LNG is less effective for women with a higher body mass index or weight, and there are also other promising EC methods being researched, like LNG-releasing intrauterine devices.
Article Synopsis
- The study investigates whether low levels of 25-hydroxyvitamin D (25(OH)D) are linked to a higher risk of miscarriage in women experiencing threatened miscarriage.
- It analyzed serum samples from 371 women, revealing a miscarriage rate of 12.1%, with no significant difference in rates between those deficient in vitamin D and those who were not.
- Notably, while lower vitamin D levels did not correlate with miscarriages overall, women presenting earlier in their pregnancy (6 weeks or less) showed a higher miscarriage rate if they were non-deficient in vitamin D.
Background: At menstruation, the functional layer of the human endometrium sheds off due to the trigger of the release of inflammatory factors, including interleukin 6 (IL-6), as a result of a sharp decline in progesterone levels, leading to tissue breakdown and bleeding. The endometrial mesenchymal stem-like cells (CD140bCD146 eMSC) located in the basalis are responsible for the cyclical regeneration of the endometrium after menstruation. Endometrial cells from the menstruation phase have been proven to secrete a higher amount of IL-6 and further enhance the self-renewal and clonogenic activity of eMSC.
View Article and Find Full Text PDFIntroduction: Low vitamin D status is prevalent among women with polycystic ovary syndrome (PCOS). The objective of the study is to assess the effect of vitamin D supplementation on (1) the ovulation rate to letrozole and (2) other reproductive, endocrine and metabolic outcomes after 1 year of supplementation in women with PCOS.
Methods And Analysis: This is a multicentre, randomised, double-blind, controlled clinical trial.
Comparison of the multiples of the median of serum anti-müllerian hormone and pregnancy outcomes in patients with gestational trophoblastic disease: A case-control study.
Cancer Med
April 2024
Article Synopsis
- Chemotherapy is important for treating gestational trophoblastic neoplasia (GTN), but its effects on fertility are not fully understood, leading to a study comparing GTN patients and those with molar pregnancies (MP).
- The study involved 57 GTN patients and analyzed serum AMH levels before and after treatment with single-agent or combination chemotherapy, revealing that combination therapy resulted in lower levels, particularly noticeable at 12 months.
- Despite the differences in hormone levels, pregnancy success rates were similar between the two groups, with longer times to first pregnancy for those on combination therapy, highlighting the need for careful patient counseling regarding fertility post-treatment.
Background: The monthly regeneration of human endometrial tissue is maintained by the presence of human endometrial mesenchymal stromal/stem cells (eMSC), a cell population co-expressing the perivascular markers CD140b and CD146. Endometrial regeneration is impaired in the presence of intrauterine adhesions, leading to infertility, recurrent pregnancy loss and placental abnormalities. Several types of somatic stem cells have been used to repair the damaged endometrium in animal models, reporting successful pregnancy.
View Article and Find Full Text PDFAdrenomedullin has a pivotal role in trophoblast differentiation: A promising nanotechnology-based therapeutic target for early-onset preeclampsia.
Sci Adv
November 2023
Article Synopsis
- Early-onset preeclampsia (EOPE) is a serious pregnancy problem that starts early but shows symptoms later on, and it's hard to predict or treat.
- A protein called adrenomedullin (ADM) is found in high amounts in the placenta during early pregnancy, and it helps with important processes in the placenta.
- Research shows that when ADM is low in pregnant women who go on to develop EOPE, it can lead to complications, but increasing ADM levels can help reduce these issues in studies with mice.
Article Synopsis
- Mosaicism is when an individual has genetically different cell populations from the same original zygote, and past studies suggested parental mosaicism could be anywhere from 0.33% to 25.9%.
- In this research, parents of children with developmental disorders who had a de novo variant were studied, collecting various biological samples to look for parental mosaicism using advanced PCR techniques.
- Out of 20 families, 20% showed parental mosaicism, with specific variants identified in two maternal cases and one paternal case, providing crucial information for assessing recurrence risk and planning medical care for future pregnancies.
Article Synopsis
- - The study aimed to determine if adding piroxicam, a cyclo-oxygenase inhibitor, to levonorgestrel (a common emergency contraception) would enhance its effectiveness after ovulation.
- - Conducted in a double-blind, placebo-controlled trial involving 860 women, the results showed that the combination of levonorgestrel and piroxicam significantly reduced the pregnancy rate compared to levonorgestrel alone (94.7% vs. 63.4% effectiveness).
- - The addition of piroxicam did not lead to significant differences in menstrual cycle changes or adverse effects, suggesting it is a safe and effective enhancement to emergency contraception.
Advanced glycation end-products and its soluble receptor are not independent predictors of incident dysglycaemia or metabolic syndrome in women with polycystic ovary syndrome: a prospective observational study.
Reprod Biol Endocrinol
May 2023
Background: To evaluate the association of serum advanced glycation end-products (AGEs) and its soluble receptor of AGE (sRAGE) levels with dysglycaemia and metabolic syndrome in women with polycystic ovary syndrome (PCOS).
Methods: This was an analysis of a cohort of women with PCOS who were prospectively recruited for a longitudinal observational study on their endocrine and metabolic profile between January 2010 and December 2013. The association of serum AGEs and sRAGE levels with dysglycaemia and metabolic syndrome at the second-year visit (the index visit) and the sixth-year visit (the outcome visit) were determined.
Factors affecting the distribution of serum anti-müllerian hormone levels among infertile Asian women: a multi-nation, multi-centre, and multi-ethnicity prospective cohort study.
Hum Reprod
July 2023
Article Synopsis
- The study investigates how factors like age, ethnicity, and BMI affect serum anti-mullerian hormone (AMH) levels in Asian women receiving fertility treatments.
- A total of 4,556 women aged 20-43 from various Asian ethnic backgrounds participated in a multi-center study, revealing that AMH levels decline significantly with age and are influenced by obesity and conditions like polycystic ovarian syndrome (PCOS).
- The findings show a mean AMH level of 3.44 ng/ml across all ages, with optimal PCOS diagnosis at a concentration of 4.0 ng/ml, indicating poorer reproductive outcomes for older women.
Human fertilization begins when a capacitated spermatozoon binds to the zona pellucida (ZP) surrounding a mature oocyte. Defective spermatozoa-ZP interaction contributes to male infertility and is a leading cause of reduced fertilization rates in assisted reproduction treatments (ARTs). Human ejaculate contains millions of spermatozoa with varying degrees of fertilization potential and genetic quality, of which only thousands of motile spermatozoa can bind to the ZP at the fertilization site.
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- A study aimed to assess how well the attachment of human embryonic stem cell-derived trophoblastic spheroids to endometrial cells can predict live birth rates for women undergoing IVF.
- Conducted at a university hospital, the research involved 240 infertile women and measured the attachment rate prior to their IVF cycles.
- Results showed that the attachment rate had a modest predictive value, especially highlighting that women aged 35 and older demonstrated higher attachment rates if they achieved live births compared to those who did not.
Purpose: To evaluate the effect of basal serum testosterone levels on the ovarian response and the cumulative live birth rate of infertile women undergoing in vitro fertilization (IVF).
Methods: It is a retrospective study in a university-affiliated assisted reproduction center in Hong Kong. Infertile women undergoing the first IVF cycle in the center between December 2012 and November 2016 with archived serum samples and available information on cumulative live birth were included for the analysis.
Pregnancy involves a wide range of adaptations in the maternal body. Maternal immune tolerance toward the foreign fetus is critical for a successful pregnancy. Decidual macrophages are the primary antigen-presenting and phagocytic cells responsible for antigen presentation and apoptotic cell removal.
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- The global rise in obesity among women of reproductive age highlights the need for comprehensive contraceptive options to protect their reproductive rights.
- Individuals with obesity often face stigma and discrimination in healthcare settings, necessitating awareness of potential biases during contraceptive care.
- The article evaluates the benefits and drawbacks of various contraceptive methods for people with obesity, emphasizing the importance of inclusive care and long-acting reversible contraceptives while considering health risks and noncontraceptive benefits.
In-vitro fertilization is an effective treatment for various causes of infertility. However, management of women with poor ovarian response or premature ovarian insufficiency remains challenging because these women have underdeveloped small ovarian follicles that do not respond to hormone treatment. In-vitro activation of small follicles has been developed but its efficiency has much room for improvement.
View Article and Find Full Text PDFObjective: To compare the intercycle variation of serum anti-Mullerian hormone (AMH) and antral follicle count (AFC) measurements over four consecutive menstrual cycles.
Design: Observational study with secondary analysis using data from two previous randomized controlled trials.
Patients: Seventy-eight women from two previous randomized trials on the effect of dehydroepiandrosterone pretreatment on ovarian response in women undergoing in vitro fertilization (IVF) treatment.
Article Synopsis
- A systematic review and meta-analysis were conducted to evaluate the effects of nonoxynol-9 (N-9), a spermicide, on human sperm motility and structure based on phase I and II clinical trials.
- Results showed that treatment with N-9 decreased the number of progressive motile sperm and shortened their penetration distance, while also damaging sperm structures like the acrosome and mitochondria.
- Overall, the findings indicate that N-9 significantly impairs sperm function, leading to reduced motility and increased risk of contraceptive failure despite its long history of use as a spermicide.
Endometrial mesenchymal stem-like cells (eMSC) reside in the basal layer of the endometrium and are responsible for cyclic regeneration during the reproductive lives of women. Myometrial cells act as a component of the niche and regulate the stem cell fate through the activation of WNT/β-catenin signaling WNT5A. Since WNT5A-responsive mechanisms on eMSC are still uncertain, we hypothesize that the WNT ligand-WNT5A works to activate WNT/β-catenin signaling through binding to Frizzled receptors (FZDs) and co-receptor low-density lipoprotein receptor-related protein 5 (LRP5).
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- The study aimed to assess the impact of the absence of continuous companion support during labor on pregnancy and neonatal outcomes during the COVID-19 pandemic in Hong Kong.
- Data were collected from 446 women with support in 2019 and 340 women without support in 2020, revealing key differences in labor experiences and infant health.
- Results showed that women without support had higher rates of labor augmentation, increased likelihood of lower Apgar scores for infants, and lower rates of immediate breastfeeding compared to those with companion support.