University of Oulu

Demir, A., Hero, M., Alfthan, H. et al. Identification of the LH surge by measuring intact and total immunoreactivity in urine for prediction of ovulation time. Hormones 21, 413–420 (2022).

Identification of the LH surge by measuring intact and total immunoreactivity in urine for prediction of ovulation time

Saved in:
Author: Demir, And1; Hero, Matti1; Alfthan, Henrik2;
Organizations: 1Pediatric Research Center, New Childrenʼs Hospital, University of Helsinki and Helsinki University Hospital, Biomedicum II, 6th floor, Tukholmankatu 8 A, FIN-00290, Helsinki, Finland
2HUSLAB, Helsinki University Hospital, Helsinki, Finland
3Department of Clinical Chemistry, Helsinki University Hospital, Helsinki, Finland
4Department of Obstetrics and Gynecology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
5Department of Obstetrics and Gynecology, Medical Research Center, PEDEGO Research Unit, University of Oulu and Oulu University Hospital, Oulu, Finland
Format: article
Version: published version
Access: open
Online Access: PDF Full Text (PDF, 2.6 MB)
Persistent link:
Language: English
Published: Springer Nature, 2022
Publish Date: 2022-11-29


Objectives: In our earlier study, we separated three different molecular forms of urinary LH-ir (U-LH-ir) by gel filtration and identified them by immunoassay in urine from regularly menstruating women on periovulatory days. U-LH-ir is composed of intact luteinizing hormone (LH), its free beta-subunit (LHβ), and the core fragment of LHβ (LHβcf), the latter two establishing the non-intact portion of LH-ir. The aim was to determine whether timing of ovulation can be improved by detecting different molecular forms of U-LH-ir in women of reproductive age.

Methods: We determined intact and total U-LH-ir in 14 regularly menstruating women on consecutive periovulatory days during the menstrual cycle. Non-intact LH-ir was calculated as the arithmetic difference between total and intact LH-ir. In addition, LH-ir was determined in both serum and urine from four of the women throughout the menstrual cycle.

Results: During the LH surge, U-LH-ir consisted mainly of intact LH and presented with an abrupt increase. Intact U-LH-ir dropped rapidly within 1 day after the surge, reaching baseline levels at the end of the luteal phase. In contrast, LHβcf in urine increased further 1 day after the surge. After this, most of the U-LH-ir consisted of LHβcf and it remained strongly elevated (over fivefold compared to intact LH) for the first 3 days after the LH surge, moderately elevated (over threefold) thereafter until day + 5, and mildly elevated until day + 7.

Conclusions: Total and non-intact LH-ir are potential add-on characteristics which can be utilized in ovulation predictor kits to measure LH-ir in urine beyond the LH surge during a broader time frame, thereby paving the way for more precise prediction of the timing of ovulation than that obtained with currently available products.

see all

Series: Hormones
ISSN: 1109-3099
ISSN-E: 2520-8721
ISSN-L: 1109-3099
Volume: 21
Issue: 3
Pages: 413 - 420
DOI: 10.1007/s42000-022-00368-9
Type of Publication: A1 Journal article – refereed
Field of Science: 3123 Gynaecology and paediatrics
Funding: Open Access funding has been provided by the University of Helsinki, including Helsinki. The study was funded by the Finnish Medical Foundation (Suomen Lääketieteen Säätiö) and Finnish Medical Society (Finska Läkaresällskapet).
Copyright information: © The Author(s) 2022. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit