Urinary concentrations of 3-(diethylcarbamoyl)benzoic acid (DCBA), a major metabolite of N,N-diethyl-m-toluamide (DEET) and semen parameters among men attending a fertility center

Effect of different starting doses of FSH on laboratory and clinical outcomes in patients with moderate AMH level

BACKGROUND

IVF and ICSI-ET are widely used ART for addressing infertility which have been developed and improved over the last four decades. COS is a crucial step in IVF/ICSI-ET, whereby medications stimulate the ovaries to produce multiple eggs. The success of the procedure depends on the number of eggs retrieved, and individualized ovarian stimulation protocols based on factors like age and ovarian reserve can optimize the chances of obtaining mature oocytes. The optimal starting dose of FSH at moderate AMH levels remains a topic of debate., tThis study aims to compare different starting doses of FSH in clinical outcomes by analyzing data from a single center.

METHODS

This retrospective study collected clinical material from patients with moderate AMH levels at 1.2 ~ 4.5 ng/mL who received IVF/ICSI-ET under a follicular phase long protocol from July 2018 to December 2021 at Guiyang Maternal and Child Health Care Hospital, China. The patients' clinical data were retrieved from the hospital's software database and divided into two groups based on FSH starting dose, as follows: lower starting dose group: FSH ≤ 150 IU; and higher starting dose group: FSH > 150 IU. Multiple laboratory and clinical outcomes were compared between the two groups.

RESULTS

A total of 1784 patients with moderate serum AMH levels who received IVF/ICSI-ET under a follicular phase long protocol were enrolled based on eligibility criteria. In the population with moderate AMH levels, a lower starting dose of FSH might have more benefit than a higher starting dose in numbers of follicles with diameters ≥ 14 mm and < 16 mm, ≥ 16 mm and < 18 mm, and ≥ 18 mm; numbers of retrieved oocytes, 2PNs, transferable embryos, high-quality embryos, and cleavage stage embryos transferred; and clinical pregnancy rate, intrauterine pregnancy rate, and parturition rate. Moreover, rFSH had a statistically significantly higher number of oocytes retrieved, number of 2PNs, and number of transferable embryos than that of patients who received uFSH.

CONCLUSIONS

The starting dose of FSH in the moderate AMH population remains controversial and a higher starting dose may not lead to more benefit in laboratory and clinical outcomes.

Altered gene expression linked to germline dysfunction following exposure of Caenorhabditis elegans to DEET

N,N-diethyl-meta-toluamide (DEET) is a commonly used synthetic insect repellent. Although the neurological effects of DEET have been widely investigated, its effects on the germline are less understood. Here, we show that exposure of the nematode Caenorhabditis elegans, which is highly predictive of mammalian reprotoxicity, resulting in internal DEET levels within the range detected in human biological samples, causes activation of p53/CEP-1-dependent germ cell apoptosis, altered meiotic recombination, chromosome abnormalities, and missegregation. RNA-sequencing analysis links DEET-induced alterations in the expression of genes related to redox processes and chromatin structure to reduced mitochondrial function, impaired DNA double-strand break repair progression, and defects during early embryogenesis. We propose that Caenorhabditis elegans exposure to DEET interferes with gene expression, leading to increased oxidative stress and altered chromatin structure, resulting in germline effects that pose a risk to reproductive health.

Semen parameters on the day of oocyte retrieval predict low fertilization during conventional insemination IVF cycles

PURPOSE

Poor fertilization during conventional IVF is difficult to predict in the absence of abnormal semen parameters; large-scale studies are lacking. The purpose of this study is to evaluate factors associated with low fertilization rates in conventional insemination IVF cycles.

METHODS

A retrospective cohort study evaluating demographic, reproductive evaluation, and IVF cycle characteristics to identify predictors of low fertilization (defined as 2PN/MII ≤ 30% per cycle). Participants were included if they were undergoing their first IVF cycle utilizing fresh autologous oocytes and conventional insemination with male partner's sperm (with normal pretreatment semen analysis). They were randomly divided into a training set and a validation set; validation modeling with logistic regression and binary distribution was utilized to identify covariates associated with low fertilization.

RESULTS

Postprocessing sperm concentration of less than 40 million/ml and postprocessing sperm motility < 50% on the day of retrieval were the strongest predictors of low fertilization in the training dataset. Next, in the validation set, cycles with either low postprocessing concentration (≤ 40 million/ml) or low postprocessing progressive motility (≤ 50%) were 2.9-times (95% CI 1.4, 6.2) more likely to have low fertilization than cycles without either risk factor. Furthermore, cycles with low postprocessing concentration and progressive motility were 13.4 times (95% CI 4.01, 45.06) more likely to have low fertilization than cycles without either risk factor.

CONCLUSIONS

Postprocessing concentration and progressive motility on the day of oocyte retrieval are predictive of low fertilization in conventional IVF cycles with normal pretreatment diagnostic semen analysis parameters.