An Electromagnetic Technique for Determination of Ovulation

E Odeblad

doi:10.3109/00016346809156617

An Electromagnetic Technique for Determination of Ovulation

ODEBLAD E

Acta Obstetricia et Gynecologica Scandinavica, 47(S8), 20-38, 1968

DOI 10.3109/00016346809156617

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RRM Academy Synopsis

Finger coils tracked ovary size to suggest ovulation in healthy women

In healthy volunteers, finger coils tracked one ovary growing after ovulation and no size split without it. In 1968, a Swedish physician tried the method on healthy young volunteers. He measured 14 ovulating cycles, 8 cycles that skipped ovulation on their own and 12 cycles where pills stopped it.

Key Findings

Ovarian size was measured through complete cycles in healthy young volunteers: 14 normal ovulatory cycles, 8 cycles of spontaneous anovulation (no ovulation, no drug) and 12 cycles of induced anovulation.
In these ovulatory cycles, one ovary, right or left, grew after the expected time of ovulation. It peaked about 5-10 days later, and the two sides differed in the corpus luteum phase.
In the 8 spontaneous anovulation cycles, both ovaries rose slightly over the cycle and followed each other fairly closely, with no difference between the two sides.
In induced anovulation with high-dose combined contraceptive pills, both ovaries stayed at a constant size all cycle, with no tendency to rise.
A single measurement had a standard error of about 1 mm when the same ovary was re-measured on the same day, in women with thin abdominal walls.

Interpretation

The report describes a new measuring method and its first use in a small group of healthy young volunteers. Basal body temperature, cervical mucus signs, cervical diameter and vaginal cytology confirmed whether ovulation occurred. The author concludes that the method can tell cycles with ovulation from cycles without it with fairly good accuracy. He states that the method cannot find the exact day of ovulation. The author limits the method to women with thin abdominal walls and ovaries that can be felt. Tenderness may make an ovary measure larger than its real size, the author notes. The paper studied only healthy young women.

RRM Context

Restorative reproductive medicine looks for ovulation in body signs across the cycle. Here, charted basal body temperature and cervical mucus signs decided which cycles had ovulated. Daily body signs served as the yardstick for a physical measurement.

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ODEBLAD E, 1968 Acta Obstetricia et Gynecologica Scandinavica

Effectiveness · Comparative Effectiveness

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Effectiveness · Comparative Effectiveness

A Comparison of Two Hormonal Fertility Monitoring Systems for Ovulation Detection: A Pilot Study

Mu Q et al., 2023 Medicina (Kaunas) Free full text on PubMed Central

Background and Accuracy in detecting ovulation and estimating the fertile window in the menstrual cycle is essential for women to avoid or achieve pregnancy. There has been a rapid growth in fertility apps and home ovulation testing kits in recent years. Nevertheless, there lacks information on how well these apps perform in helping users understand their fertility in the menstrual cycle. This pilot study aimed to evaluate and compare the beginning, peak, and length of the fertile window as determined by a new luteinizing hormone (LH) fertility tracking app with the Clearblue Fertility Monitor (CBFM). A total of 30 women were randomized into either a quantitative Premom or a qualitative Easy@Home (EAH) LH testing system. The results of the two testing systems were compared with the results from the CBFM over three menstrual cycles of use. Potential LH levels for estimating the beginning of the fertile window were calculated along with user acceptability and satisfaction. The estimates of peak fertility by the Premom and EAH LH testing were highly correlated with the CBFM peak results (R = 0.99, p < 0.001). The participants had higher satisfaction and ease-of-use ratings with the CBFM compared to the Premom and EAH LH testing systems. LH 95% confidence levels for estimating the beginning of the fertile window were provided for both the Premom and EAH LH testing results. Our pilot study findings suggest that the Premom and EAH LH fertility testing app can accurately detect impending ovulation for women and are easy to use at home. However, successful utilization of these low-cost LH testing tools and apps for fertility self-monitoring and family planning needs further evaluation with a large and more diverse population.

Methods · Sympto-Thermal Method

Determination of the fertile window: reproductive competence of women--European cycle databases

Frank-Herrmann P et al., 2005 Gynecol Endocrinol

The objective of the present paper is to review the main results of recent European cycle databases on ovulation detection and determination of the fertile window performed by the women themselves. The ongoing German Long-term Cycle Database currently comprises 32788 prospectively collected cycle charts of 1551 women, the I European Cycle Database (10 countries) 1328 women/19048 cycles, the II European Cycle Database (six countries) 782 women/6724 cycles, and the World Health Organization Database (one European country) 234 women/2808 cycles. The women record cycle parameters (cervical mucus changes, temperature rise, etc.), family planning intention and sexual behavior. With the symptothermal method of natural family planning it has become possible to determine the fertile window in order to avoid pregnancy with a method effectiveness of 0.3%. According to a small sub-study, the ovulation time observed by the women themselves correlates closely with ovulation detected by ultrasound and measurement of luteinizing hormone (correlation within 1 day in 89% of the 62 cycles). Fertility awareness methods can be integrated into the management of sub-fertility. They seem to shorten the time to pregnancy. Self-observation of the fertile window puts women into a position to develop a high level of reproductive competence that could be used much more in different areas than is currently the case.

DOI 10.3109/00016346809156617 10.3109/00016346809156617 ODEBLAD et al. 1968, ODEBLAD 1968