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

Marte Saupstad; Sara J Bergenheim; Jeanette W Bogstad; Morten R Petersen; Anna Klajnbard; Lisbeth Prætorius; Nina L C Freiesleben; Anne L Englund; Ellen C L Løkkegaard; Ulla B Knudsen; Merete Husth; Birgit Alsbjerg; Julie E Møller; Tine V Dam; Julie L Forman; Anja Pinborg; Kristine Løssl

doi:10.1016/j.rbmo.2024.103862

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

Reprod Biomed Online. 2024 Feb 6;49(1):103862. doi: 10.1016/j.rbmo.2024.103862. Online ahead of print.

Authors

Marte Saupstad¹, Sara J Bergenheim², Jeanette W Bogstad², Morten R Petersen², Anna Klajnbard³, Lisbeth Prætorius⁴, Nina L C Freiesleben⁵, Anne L Englund⁶, Ellen C L Løkkegaard⁷, Ulla B Knudsen⁸, Merete Husth⁹, Birgit Alsbjerg¹⁰, Julie E Møller², Tine V Dam², Julie L Forman¹¹, Anja Pinborg¹², Kristine Løssl¹²

Affiliations

¹ The Fertility Clinic, Department of Gynaecology, Fertility and Obstetrics, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.. Electronic address: marte.saupstad@regionh.dk.
² The Fertility Clinic, Department of Gynaecology, Fertility and Obstetrics, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.
³ Department of Obstetrics and Gynaecology, The Fertility Clinic, Copenhagen University Hospital Herlev, Herlev, Denmark.
⁴ Department of Obstetrics and Gynaecology, The Fertility Clinic, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark.
⁵ Department of Obstetrics and Gynaecology, The Fertility Clinic, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark.; Institute of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
⁶ Department of Obstetrics and Gynaecology, The Fertility Clinic, Zealand University Hospital Koege, Koege, Denmark.
⁷ Department of Obstetrics and Gynaecology, Copenhagen University Hospital North Zealand, North Zealand Hospital, Hilleroed, Denmark.; Institute of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
⁸ Department of Obstetrics and Gynaecology, The Fertility Clinic, The Regional Hospital Horsens, Horsens, Denmark.
⁹ The Fertility Unit, Aalborg University Hospital, Aalborg University Hospital South, Aalborg, Denmark.
¹⁰ The Fertility Clinic, Skive Regional Hospital, Skive, Denmark.
¹¹ Section of Biostatistics, Department of Public Health, University of Copenhagen, Copenhagen, Denmark.
¹² The Fertility Clinic, Department of Gynaecology, Fertility and Obstetrics, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.; Institute of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.

PMID: 38735231
DOI: 10.1016/j.rbmo.2024.103862

Abstract

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. Associations between the serum progesterone concentration on the day of blastocyst transfer and CPR, pregnancy rate and pregnancy loss rate (PLR) were examined between groups with low and higher progesterone concentrations using the 25th and 10th percentiles as cut-offs. Multivariate logistic regression analyses were performed to adjust for potential confounding factors.

Results: Progesterone concentrations on the day of blastocyst transfer in mNC-FET without LPS ranged from 4.9 to 91.8 nmol/l, with the 25th and 10th percentiles at 29.0 nmol/l and 22.5 nmol/l, respectively. Serum progesterone concentrations did not differ between women with or without a clinical pregnancy (mean [SD] 38.5 [14.0] versus 36.8 [12.4] nmol/l; P = 0.350). Furthermore, the CPR, pregancy rate and PLR were similar in women with low or high progesterone concentrations when using the 25th or the 10th progesterone percentile as cut-off. Multivariate regression analyses showed no association between progesterone concentrations and CPR.

Conclusions: No association was found between progesterone concentration on the day of blastocyst transfer and pregnancy outcome in women undergoing mNC-FET without progesterone LPS.

Keywords: Blastocyst transfer; Clinical pregnancy rate; Frozen embryo transfer; Modified natural cycle; Progesterone.