MSMaike Katja Sachs

Maike Katja Sachs

*This is an algorithmically generated author record based on publicly available information.

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Maike Katja Sachs has a total of 59 co-authors. Here are the top co-authors by number of shared publications:


Latest Publications

  • Open Access

    Can Wrist-Worn Medical Devices Correctly Identify Ovulation?

    by Angela Niggli, Martina Rothenbühler, Maike Sachs, Brigitte Leeners

    (1) Background: Hormonal fluctuations across the menstrual cycle lead to multiple changes in physiological parameters such as body temperature, cardiovascular function, respiratory rate and perfusion. Electronic wearables analyzing those parameters might present a convenient alternative to urinary ovulation tests for predicting the fertile window. (2) Methods: We conducted a prospective observational study including women aged 18–45 years without current hormonal therapy who used a wrist-worn medical device and urinary ovulation tests for a minimum of three cycles. We analyzed the accuracy of both the retrospective and prospective algorithms using a generalized linear mixed-effects model. The findings were compared to real-world data from bracelet users who also reported urinary ovulation tests. (3) Results: A total of 61 study participants contributing 205 cycles and 6081 real-life cycles from 3268 bracelet users were included in the analysis. The mean error in identifying ovulation with the wrist-worn medical device retrospective algorithm in the clinical study was 0.31 days (95% CI −0.13 to 0.75). The retrospective algorithm identified 75.4% of fertile days, and the prospective algorithm identified 73.8% of fertile days correctly within the pre-specified equivalence limits (±2 days). The quality of the retrospective algorithm in the clinical study could be confirmed by real-world data. (4) Conclusion: Our data indicate that wearable sensors may be used to accurately detect the periovulatory period.


  • Transcriptomic signature of luteinized cumulus cells of oocytes developing to live birth after women received intracytoplasmic sperm injection

    by Maike K. Sachs, Sofia Makieva, Ana Velasco Gil, Min Xie, Fabian Ille, Vincent Salvadori, Meret Schmidhauser, Mara D. Saenz-De-Juano, Susanne E. Ulbrich, Brigitte Leeners


  • Open Access

    Physical Activity in Women with Endometriosis: Less or More Compared with a Healthy Control?

    by Maike Katja Sachs, Ioannis Dedes, Samia El-Hadad, Annika Haufe, Dalia Rueff, Alexandra Sabrina Kohl Schwartz, Felix Haeberlin, Stephanie von Orelli, Markus Eberhard, Brigitte Leeners

    Background: Endometriosis, i.e., endometrial-like tissue outside the uterus, is a chronic inflammatory condition affecting physical functioning. However, the specific levels of physical activity (PA) in the context of endometriosis and different disease symptoms remain unclear. Methods: This multi-center, cross-sectional study compared PA levels and influencing factors in endometriosis patients and non-endometriosis patients. Data were collected through questionnaires. Endometriosis was surgically confirmed. A statistical analysis was performed with appropriate tests. Results: The study included 460 women with endometriosis and 460 age-matched women without this condition. The two groups did not differ significantly in terms of age, education level, or stable partnership. Women with endometriosis exhibited lower PA levels, practicing fewer hours of sports weekly and climbing fewer stairs daily compared to the control group. These differences remained significant after controlling for confounding factors. Factors such as endometriosis, current dysmenorrhea, and depression were associated with decreased PA. Conclusions: These findings suggest that women with endometriosis engage in less PA compared to those without this condition. These results highlight the need for interventions to promote increased PA in endometriosis patients and harness the associated health benefits. Further research is warranted to explore the underlying mechanisms and develop tailored exercise therapies for this population.


  • Open Access

    Fertilität bei Endometriose

    by Maike Katja Sachs, Brigitte Leeners

    Zusammenfassung: Hintergrund: Das Vorliegen einer Endometriose geht gehäuft mit einem unerfüllten Kinderwunsch einher. Hierbei wird von einem multifaktoriellen Einfluss der endometriosebedingten systemischen Entzündungsreaktion auf verschiedenen Ebenen der Fertilität ausgegangen. Dem entgegenwirkend haben Techniken der assistierten Reproduktion („assisted reproductive techniques“ [ART]) eine entscheidende Bedeutung im Rahmen des Kinderwunschs erlangt. Ziel der Arbeit: Dieser Beitrag geht auf die multifaktoriellen Auswirkungen der Endometriose auf die weibliche Fertilität ein. Unter anderem werden Schwangerschaftsoutcomes bei Endometriose, der Erfolg der ART, Operationsindikationen und die Möglichkeit eines „egg freezing“ betrachtet. Material und Methoden: PubMed sowie die aktuellen Leitlinien der European Society of Human Reproduction and Embryology (ESHRE) von 2022 wurden für die Literaturrecherche herangezogen. Es wurden Suchbegriffe zu Fertilität und Endometriose verwendet. Hierbei wurden insbesondere neuere Metaanalysen und Arbeiten aus bekannten Fachzeitschriften mit einem hohen Impact Factor ausgewählt. Ergebnisse und Schlussfolgerung: Der Zusammenhang zwischen Endometriose und Subfertilität ist bekannt. Eine Anwendung von ART stellt eine sinnvolle und erfolgreiche Therapie der endometriosebedingten Fertilitätseinschränkungen dar. Operationsindikationen im Rahmen des Kinderwunschs bei Endometriose sind vorsichtig abzuwägen, eine Verbesserung der Fertilität ist in Ausnahmen möglich. Liegt bereits in jüngerem Alter eine geringe Eizellreserve vor, sollte eine Kryokonservierung von Eizellen erwogen werden. Eine Endometriosediagnose bedarf in Abhängigkeit von Lokalisation und Ausdehnung der Läsionen einer engmaschigen Überwachung in der Schwangerschaft. Grund hierfür ist unter anderem eine erhöhte Frühabort- und Frühgeburtenrate.


  • Open Access

    Higher miscarriage rate in subfertile women with endometriosis receiving unbiopsied frozen-warmed single blastocyst transfers

    by M. K. Sachs, S. Makieva, I. Dedes, D. R. Kalaitzopoulos, S. El-Hadad, M. Xie, A. Velasco, R. Stiller, B. Leeners

    Background: Assisted reproductive technology treatment is recommended to overcome endometriosis-associated infertility but current evidence is controversial. Endometriosis is associated with lower antral follicle count (AFC) and oocyte yield but similar clinical outcomes compared to controls. Unaffected ovarian stimulation response and embryological outcomes but lower clinical pregnancy and live birth rates and higher miscarriage rates have been reported, implying direct impact on endometrial receptivity. With evidence emerging on the benefit of frozen-warmed and blastocyst stage transfer, we investigated ART outcomes in endometriosis using homogeneous case-control groups.Methods: This is a retrospective observational case-control study including n = 66 frozen-warmed unbiopsied single blastocyst transfers of patients with endometriosis and n = 96 of women exhibiting idiopathic sterility. All frozen-warmed transfers followed artificial endometrial preparation.Results: In control women, the mean number of oocytes recovered at oocyte pick up was higher compared to women with endometriosis (15.3 ± 7.1 vs. 12.7 ± 5.2, p = 0.025) but oocyte maturation index (mature oocytes/total oocytes at oocyte pick up) was significantly higher for endometriosis (48.2% vs. 34.0%, p = 0.005). The same was shown for the subgroup of 44 endometriosis patients after endometrioma surgery when compared with controls (49.1% vs. 34.0%, p = 0.014). Clinical pregnancy rate was not higher in endometriosis but was close to significance (47.0% vs. 32.3%, p = 0.059) while live birth rate was comparable (27.3% vs. 32.3%, p = 0.746). Miscarriage rate was higher in the endometriosis group (19.7% vs. 7.3%, p = 0.018). A significantly higher AFC was observed in the control group in comparison with the endometriosis group (16.3 ± 7.6 vs. 13.4 ± 7.0, p = 0.014). Live birth rate did not differ when comparing all endometriosis cases (p = 0.746), ASRM Stage I/II and Stage III/IV (p = 0.348 and p = 0.888) with the control group but the overall pregnancy rate was higher in ASRM Stage I/II (p = 0.034) and miscarriage rate was higher in ASRM Stage III/IV (p = 0.030) versus control.Conclusion: Blastocyst transfers in women with endometriosis originate from cycles with lower AFC but higher share of mature oocytes than in control women, suggesting that endometriosis might impair ovarian reserve but not stimulation response. A higher miscarriage rate, independent of blastocyst quality may be attributed to an impact of endometriosis on the endometrium beyond the timing of implantation.


  • Open Access

    Stage 2: The Vaginal Flora in Women Undergoing Fetal Spina Bifida Repair and Its Potential Association with Preterm Rupture of Membranes and Preterm Birth

    by Fanny Tevaearai, Maike Katja Sachs, Samia El-Hadad, Ladina Vonzun, Ueli Moehrlen, Luca Mazzone, Martin Meuli, Franziska Krähenmann, Nicole Ochsenbein-Kölble

    Introduction: Vaginal dysbiosis affects pregnancy outcomes, however, the relevance of abnormal findings on pre/post-surgical vaginal culture in women undergoing fetal spina bifida (fSB) repair is unknown. Objectives: To describe the incidence of normal and abnormal pre- and post-surgical vaginal microorganisms in fSB patients and to investigate potential associations between the type of vaginal flora and the occurrence of preterm prelabour rupture of membranes (PPROM) and preterm birth (PTB). Methods: 99 women undergoing fSB repair were eligible (2010–2019). Pre-surgical vaginal culture was routinely taken before surgery. Post-surgical cultures were taken on indication. Vaginal flora was categorized into four categories: healthy vaginal flora (HVF), bacterial vaginosis (BV), desquamative inflammatory vaginitis (DIV), and yeast infection. Results: The incidence of HVF, BV, DIV, or yeast infections was not statistically different between the pre- and postoperative patients. Furthermore, an abnormal pre/post-surgical vaginal flora was not associated with PPROM (OR 1.57 (0.74–3.32), p = 0.213)/OR 1.26 (0.62–2.55), p = 0.515), or with PTB (OR 1.19 (0.82–1.73), p = 0.315)/(OR 0.86 (0.60–1.24), p = 0.425). Conclusions: Abnormal vaginal microbiome was not associated with PPROM and PTB when appropriate treatment was performed.


  • Open Access

    Influence of Obesity and Unemployment on Fertility Rates: A Multinational Analysis of 30 Countries from 1976 to 2014

    by Deirdre Maria König-Castillo, Johannes Ott, Daniel König, Marlene Hager, Maike Katja Kahr, Georg Dorffner

    Background: The rationale of a postulated decrease in fertility rate development is still being debated. Among the multiple influencing factors, socioeconomic variables and their complex influence are of particular interest. Methods: Data on socioeconomic and health variables from 1976–2014 of 30 countries within the OECD region were analysed for their respective influence on fertility rates by using mixed-effect regression models. Results: A significant negative influence of the increase in unemployment rate on the following year’s changes in fertility rate in Western (−0.00256; p < 0.001) as well as Eastern European (−0.0034; p < 0.001) countries was revealed. The effect of being overweight was significant for Western European (−0.00256; p < 0.001) countries only. When analysing the whole OECD region, an increase in unemployment retained its significant negative influence on the fertility rate (−0.0028; p < 0.001), while being overweight did not. Interestingly, divergent influences of time were revealed and fertility rates increased with time in Eastern Europe while they decreased in Western Europe. Conclusion: Importantly, a significant negative influence of increase in unemployment on the fertility rate was revealed—irrespective of the region and time analysed. Furthermore, an adverse effect of being overweight on the fertility rate in Western European countries was revealed. Interestingly, time was associated with a decreasing fertility rate in Western but not in Eastern Europe.


  • Open Access

    The Accuracy of Wrist Skin Temperature in Detecting Ovulation Compared to Basal Body Temperature: Prospective Comparative Diagnostic Accuracy Study

    by Tracy Y Zhu, Martina Rothenbühler, Györgyi Hamvas, Anja Hofmann, JoEllen Welter, Maike Kahr, Nina Kimmich, Mohaned Shilaih, Brigitte Leeners

    Background: As a daily point measurement, basal body temperature (BBT) might not be able to capture the temperature shift in the menstrual cycle because a single temperature measurement is present on the sliding scale of the circadian rhythm. Wrist skin temperature measured continuously during sleep has the potential to overcome this limitation. Objective: This study compares the diagnostic accuracy of these two temperatures for detecting ovulation and to investigate the correlation and agreement between these two temperatures in describing thermal changes in menstrual cycles. Methods: This prospective study included 193 cycles (170 ovulatory and 23 anovulatory) collected from 57 healthy women. Participants wore a wearable device (Ava Fertility Tracker bracelet 2.0) that continuously measured the wrist skin temperature during sleep. Daily BBT was measured orally and immediately upon waking up using a computerized fertility tracker with a digital thermometer (Lady-Comp). An at-home luteinizing hormone test was used as the reference standard for ovulation. The diagnostic accuracy of using at least one temperature shift detected by the two temperatures in detecting ovulation was evaluated. For ovulatory cycles, repeated measures correlation was used to examine the correlation between the two temperatures, and mixed effect models were used to determine the agreement between the two temperature curves at different menstrual phases. Results: Wrist skin temperature was more sensitive than BBT (sensitivity 0.62 vs 0.23; P<.001) and had a higher true-positive rate (54.9% vs 20.2%) for detecting ovulation; however, it also had a higher false-positive rate (8.8% vs 3.6%), resulting in lower specificity (0.26 vs 0.70; P=.002). The probability that ovulation occurred when at least one temperature shift was detected was 86.2% for wrist skin temperature and 84.8% for BBT. Both temperatures had low negative predictive values (8.8% for wrist skin temperature and 10.9% for BBT). Significant positive correlation between the two temperatures was only found in the follicular phase (rmcorr correlation coefficient=0.294; P=.001). Both temperatures increased during the postovulatory phase with a greater increase in the wrist skin temperature (range of increase: 0.50 °C vs 0.20 °C). During the menstrual phase, the wrist skin temperature exhibited a greater and more rapid decrease (from 36.13 °C to 35.80 °C) than BBT (from 36.31 °C to 36.27 °C). During the preovulatory phase, there were minimal changes in both temperatures and small variations in the estimated daily difference between the two temperatures, indicating an agreement between the two curves. Conclusions: For women interested in maximizing the chances of pregnancy, wrist skin temperature continuously measured during sleep is more sensitive than BBT for detecting ovulation. The difference in the diagnostic accuracy of these methods was likely attributed to the greater temperature increase in the postovulatory phase and greater temperature decrease during the menstrual phase for the wrist skin temperatures.


  • Open Access

    The Accuracy of Wrist Skin Temperature in Detecting Ovulation Compared to Basal Body Temperature: Prospective Comparative Diagnostic Accuracy Study (Preprint)

    by Tracy Y Zhu, Martina Rothenbühler, Györgyi Hamvas, Anja Hofmann, JoEllen Welter, Maike Kahr, Nina Kimmich, Mohaned Shilaih, Brigitte Leeners

    BACKGROUND As a daily point measurement, basal body temperature (BBT) might not be able to capture the temperature shift in the menstrual cycle because a single temperature measurement is present on the sliding scale of the circadian rhythm. Wrist skin temperature measured continuously during sleep has the potential to overcome this limitation. OBJECTIVE This study compares the diagnostic accuracy of these two temperatures for detecting ovulation and to investigate the correlation and agreement between these two temperatures in describing thermal changes in menstrual cycles. METHODS This prospective study included 193 cycles (170 ovulatory and 23 anovulatory) collected from 57 healthy women. Participants wore a wearable device (Ava Fertility Tracker bracelet 2.0) that continuously measured the wrist skin temperature during sleep. Daily BBT was measured orally and immediately upon waking up using a computerized fertility tracker with a digital thermometer (Lady-Comp). An at-home luteinizing hormone test was used as the reference standard for ovulation. The diagnostic accuracy of using at least one temperature shift detected by the two temperatures in detecting ovulation was evaluated. For ovulatory cycles, repeated measures correlation was used to examine the correlation between the two temperatures, and mixed effect models were used to determine the agreement between the two temperature curves at different menstrual phases. RESULTS Wrist skin temperature was more sensitive than BBT (sensitivity 0.62 vs 0.23; P<.001) and had a higher true-positive rate (54.9% vs 20.2%) for detecting ovulation; however, it also had a higher false-positive rate (8.8% vs 3.6%), resulting in lower specificity (0.26 vs 0.70; P=.002). The probability that ovulation occurred when at least one temperature shift was detected was 86.2% for wrist skin temperature and 84.8% for BBT. Both temperatures had low negative predictive values (8.8% for wrist skin temperature and 10.9% for BBT). Significant positive correlation between the two temperatures was only found in the follicular phase (rmcorr correlation coefficient=0.294; P=.001). Both temperatures increased during the postovulatory phase with a greater increase in the wrist skin temperature (range of increase: 0.50 °C vs 0.20 °C). During the menstrual phase, the wrist skin temperature exhibited a greater and more rapid decrease (from 36.13 °C to 35.80 °C) than BBT (from 36.31 °C to 36.27 °C). During the preovulatory phase, there were minimal changes in both temperatures and small variations in the estimated daily difference between the two temperatures, indicating an agreement between the two curves. CONCLUSIONS For women interested in maximizing the chances of pregnancy, wrist skin temperature continuously measured during sleep is more sensitive than BBT for detecting ovulation. The difference in the diagnostic accuracy of these methods was likely attributed to the greater temperature increase in the postovulatory phase and greater temperature decrease during the menstrual phase for the wrist skin temperatures.

  • Open Intrauterine Fetal Myelomeningocele Repair: Changes in the Surgical Procedure and Perinatal Complications during the First 8 Years of Experience at a Single Center

    by Maike K. Kahr, Franziska M. Winder, Ladina Vonzun, Luca Mazzone, Ueli Moehrlen, Martin Meuli, Margaret Hüsler, Franziska Krähenmann, Roland Zimmermann, Nicole Ochsenbein-Kölble

    Introduction: Open fetal myelomeningocele (fMMC) repair is nowadays a therapeutic option in selected cases. We aimed to evaluate changes in maternal and fetal outcome after fMMC repair during the first 8 years of experience at a tertiary referral fetal medicine center in Switzerland. ­Materials and Methods: Between 2010 and 2018, fMMC repair and delivery of the neonate via planned cesarean section was performed in 67 cases. Cases were retrospectively stratified into 2 groups: a “training phase” (TP) with supervision from an external surgeon during 11 operations (2010–2014, 15 cases) followed by an “experienced phase” (EP, 2014–2018, 52 cases); each phase lasted about 4 years. Both phases were compared with regard to various maternal and fetal outcome parameters. Results: Analyses did not reveal differences between TP and EP in major outcome parameters such as gestational age at delivery, chorionic membrane separation, or the incidence of placental abruption. Although more complex surgical techniques were applied in EP (e.g., dermal closure using a rotational flap), surgery time was not different from TP. At the same time, surgical complications such as oligohydramnios (27 vs. 8%, p = 0.046) with MRI-confirmed leakage (13 vs. 4%, nonsignificant) and subchorionic hematoma (20 vs. 2%, p = 0.009) were less common in EP than TP. Conclusions: This study shows that the level of competence at our center with regard to major perinatal outcome parameters was already high in the first years of fMMC repair. However, more complex surgical techniques and significantly less minor complications were observed during the most recent years.