Psychosocial and physical wellbeing in women and male partners undergoing immediate versus postponed modified natural cycle frozen embryo transfer after ovarian stimulation and oocyte pick-up: a sub-study of a randomized controlled trial.

Study Question: Are there differences in psychosocial and physical wellbeing among women and male partners undergoing modified natural cycle (mNC) frozen embryo transfer (FET) in immediate compared to postponed cycles after ovarian stimulation (OS) and oocyte pick-up (OPU)?

Summary Answer: Significantly more women in the immediate group reported physical symptoms than women in the postponed group whilst fewer were emotionally affected by waiting time, although the latter difference lost statistical significance after adjustment for multiple testing.

What Is Known Already: Infertility and fertility treatment are known to cause psychosocial distress in women and couples longing for a child. The treatment may be long-term and delayed for various reasons, such as the elective postponement of FET after a fresh transfer without pregnancy or an elective freeze-all cycle, possibly further increasing the level of distress.

Progesterone concentrations on blastocyst transfer day in modified natural cycle frozen embryo transfer cycles.

Research Question: Are serum progesterone concentrations on the day of modified natural cycle (mNC) frozen blastocyst transfer (FET) without luteal phase support (LPS) associated with clinical pregnancy rate (CPR)?

Design: Data were collected between January 2019 and October 2022 as a sub-study of an ongoing randomized controlled trial assessing pregnancy outcomes in mNC-FET. The sub-study included all women (n = 209) randomized to mNC-FET without LPS at the time of data extraction. Participants were aged 18-41 years, had regular menstrual cycles and underwent mNC-FET treatment with single-blastocyst transfer.

Association between the length of in vitro embryo culture, mode of ART, and the initial endogenous hCG rise in ongoing singleton pregnancies.

Study Question: Is there an association between the length of in vitro culture, mode of ART and the initial endogenous hCG rise, in cycles with a foetal heartbeat after single embryo transfer (ET) and implantation?

Summary Answer: Both the length of in vitro culture and the mode of ART have an impact on the initial endogenous rise in hCG in singleton pregnancies.

What Is Known Already: Different factors have been identified to alter the kinetics of hCG in pregnancies. Current studies show conflicting results regarding the kinetics of hCG after different types of ART (fresh vs frozen ET (FET)), the inclusion or not of preimplantation genetic testing (PGT), and the length of time in in vitro culture.

The prevalence of late-follicular phase progesterone elevation and impact on the ongoing pregnancy rate after fresh and frozen blastocyst transfer. Sub-study of an RCT.

The effect of late-follicular phase progesterone elevation (LFPE) during ovarian stimulation on reproductive outcomes in ART treatment remains controversial, but recent studies indicate lower pregnancy rates with rising progesterone levels. This study aims to investigate the prevalence of late-follicular phase progesterone elevation (LFPE) and possible impact on ongoing pregnancy rate after fresh or frozen blastocyst transfer in a sub-study setting of a randomised controlled trial. A total of 288 women were included (n=137 and n=151 in the fresh transfer and freeze-all group, respectively).