Changes of salivary estrogen levels for detecting the fertile period

https://doi.org/10.1016/j.ejogrb.2015.08.007Get rights and content

Abstract

Objectives

Is the saliva test, Geratherm ovu control, as accurate as the established urinary luteinizing hormone (LH) test for detecting ovulation and the following the fertile period?

Study design

The voluntary participants were 74 healthy women with regular menstrual cycles and not using any hormonal contraceptives. The women used Geratherm ovu control, a small plastic hand-held microscope, for detecting the fertile period. A drop of saliva from sublingual was put onto the lens of the microscope. Three results were possible: non-fertile (dot pattern), transitional and fertile (ferning pattern).

The participants performed the saliva test from the 5th till the 22nd day of the menstrual cycle and noted the respective result in a table. In addition to Geratherm ovu control, the EXACTO test for determining urinary LH concentration and the time of peak fertility was also performed.

Results

Positive LH shows a sharp increase beginning on the 10th cycle day with a maximum on the 17th cycle day. The curve for positive saliva and questionable positive saliva (one curve) is almost parallel with the curve for positive LH, reaching a maximum on the 16th cycle day. There is a high level of conformity for the same test results from the 5th (100%) till the 14th (84%) cycle day and from the 18th (80%) till the 22nd (96%) cycle day which corresponds to the pre- and post-ovulatory period.

Conclusion

The saliva and the LH test both detect the fertile window of a menstrual cycle. Caused by the different hormones (estrogen for the saliva and LH for the LH test) leading to the respective positive test results, saliva turns positive 24 h before LH. Consequently, the saliva test can be used as an ovulation test and help women maximize their chances of conceiving. There is also a high congruence between LH and saliva in the pre- and post-ovulatory period, indicating that the saliva test can also be used for contraception purposes.

Introduction

For approximately 50 years, urinary hormone assays have been used to help recognize the fertile phase of the menstrual cycle [1], [2]. These tests can be applied by women who want to prevent pregnancy by using Fertility Awareness-Based Methods (FABM). In contrast to chemical contraception, this kind of natural family planning works without intervening in the hormonal cycles [3]. The Standard Days Method (SDM), cervical mucus method or basal body temperature are further examples for FABM. The cervical mucus method is one of the most widely used biological markers for self-estimating the beginning and the end of the fertile phase in a menstrual cycle by recognizing cyclical changes in the amount or consistency of cervical secretions [4], [5], [6]. It is usually considered that the start of the fertile interval generally corresponds to a significant rise in estrogen levels which leads to secretion of estrogenic cervical mucus and thus changes in vaginal discharge [7], [8], [9]. Similar to self-observing ferning patterns in cervical mucus, saliva changes in a similar manner during the menstrual cycle. The ferning is caused by NaCl which cyclically increases under the influence of estrogen and coincides with the female fertile period [10], [11].

In contrast to the cervical mucus method, the urinary testing methods measure the concentration of the hormone to be examined, in order to identify the ovulatory period. Three methods have been discussed and proposed in scientific literature: oestrone-3-glucuronide (E1G), pregnanediol-3a-glucuronide (PDG) and luteinizing hormone (LH) [12], [13].

Fig. 1 gives an overview of the hormonal changes during the menstrual cycle which will be important for the analysis of the results. Responding to low levels of estrogen, the hypothalamus sends a signal to the anterior pituitary gland to release follicle stimulating hormone (FSH). In addition to stimulating ovarian follicular growth, FSH stimulates the granulosa cells of the follicle to produce gradually increasing amounts of estrogen. As the estrogen production accelerates, it begins to inhibit FSH and at the same time stimulates luteinizing hormone (LH). This leads to a major surge in LH with a peak 12 to 24 h before ovulation. This surge in LH is accompanied by a parallel surge in FSH and estrogen [14], [15]. After the peak of LH, FSH and estradiol, continuing secretion of LH causes the granulosa cells to produce progesterone which is produced for about 10 days in the absence of pregnancy. Afterwards, progesterone and estrogen concentration rapidly decline which leads to the bleeding. Responding to the low levels of estrogen, the hypothalamus again causes release of FSH and the cycle begins again [16].

One method of examining the validity of fertility monitors using saliva is to compare them with established markers of ovulation, such as LH in urine. The aim of this study was to determine the accuracy of the hand-held microscope, Geratherm ovu control, by comparing it with the established urinary LH test EXACTO.

Section snippets

Subjects

The voluntary participants were 74 healthy women with regular menstrual cycles (25–35 days) and not using any hormonal contraceptives or intrauterine devices (baseline period). Pregnancy and breast-feeding were also exclusion criteria. The mean age was 24 years [20–35]. The sociodemographic data are shown in Table 1. There was no ethic committee vote necessary, because not patients, but voluntary women with informed consent were participating in the study.

At study initiation, each woman

Methods

The women used Geratherm ovu control, a small plastic hand-held microscope, for detecting the fertile period. The test was performed during the morning or afternoon either before or at least 3 h after eating, drinking, smoking or teeth brushing. A drop of saliva from sublingual was put onto the lens of the microscope and after 10–15 min of drying, it was ready for evaluation. Fig. 2 shows the three possible results: (a) simple dot patterns and lines indicate no ovulation, (b) small ferning

Results

For better analysis of the collected data, positive saliva and questionable positive saliva were both considered to be positive. In the following, positive saliva describes the sum of positive and questionable positive saliva for the respective cycle day.

Positive LH shows a sharp increase beginning on the 10th cycle day with a maximum on the 17th cycle day, a small descending plateau till the 18.5th cycle day and afterwards a sharp decrease till the 22nd cycle day. The curve for positive saliva

Comments

The results of this study show cyclical changes in saliva as well as in urinary LH concentration. The maximum for positive saliva was shown on the 16th cycle day, whereas LH had its maximum on the 17th cycle day. This one-day difference concerning the maximum of the two tests is caused by the time sequences of hormonal changes: estrogen (responsible for the saliva test) and LH respectively (responsible for the LH test). These hormonal changes have already been described above (Fig. 1).

Conclusion

The saliva and the LH test both detect the fertile window of a menstrual cycle. Caused by the different hormones (estrogen for the saliva and LH for the LH test) leading to the respective positive test results, saliva turns positive 24 h before LH. Consequently, the saliva test can be used as an ovulation test and help women maximize their chances of conceiving.

Conflict of interest

The authors have no conflicts of interest or financial ties to disclose.

References (26)

  • J.L. Bigelow et al.

    Mucus observations in the fertile window: a better predictor of conception than timing of intercourse

    Hum Reprod

    (2004)
  • D.F. Katz et al.

    Analysis of pre-ovulatory changes in cervical mucus hydration and sperm penetrability

    Adv Contracept

    (1997)
  • M. Menarguez et al.

    Morphological characterization of different human cervical mucus types using light and scanning electron microscopy

    Hum Reprod

    (2003)
  • Cited by (12)

    • Enhanced determination of fertility hormones in saliva at disposable immunosensing platforms using a custom designed field-portable dual potentiostat

      2019, Sensors and Actuators, B: Chemical
      Citation Excerpt :

      Afterwards, the rapid decrease in P4 and estrogen concentration, results in the bleeding. In response to the low levels of estrogen, the hypothalamus again triggers the FSH release and the cycle starts again [2]. In 2016, Blake et al. [3] reported standardized protocols for evaluating women’s fertility based on LH assays and, following this proposal, various ELISA kits for LH are currently available.

    View all citing articles on Scopus
    View full text