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The Circadian Variability of Serum Progesterone During the Day of a Frozen Embryo Transfer

The Circadian Variability of Serum Progesterone During the Day of a Frozen Embryo Transfer in an Artificially Prepared Cycle and in a Modified Natural Cycle

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05511272
Acronym
CIRCAPRO
Enrollment
44
Registered
2022-08-22
Start date
2022-08-15
Completion date
2023-12-01
Last updated
2023-12-19

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Fertility Disorders

Brief summary

Serum progesterone levels will be evaluated at four different time points during the day of an artificially prepared frozen embryo transfer cycle (HRT FET cycle) and a modified natural cycle frozen embryo transfer cycle (mNC FET cycle) (at 08:00, 12:00, 16:00 and 20:00).The pairwise percentage differences in serum progesterone levels for each patient will be calculated. The intra-day variability of progesterone will be analyzed using mixed models. Pregnancy outcomes will also be assessed. The sample size calculated consisted of 22 patients for the HRT-FET study and 22 patients for the mNC FET study.

Detailed description

In the HRT FET, estradiol valerate (Progynova) will be administered for endometrial preparation. If the endometrial thickness will be ≥ 6,5 mm during an ultrasound scan planned following an initial period of estrogen priming, micronized vaginal progesterone will be started (Utrogestan 800 mg/d). The transfer of a single blastocyst will be performed on the 6th day of progesterone administration. In a modified NC FET, there is no intake of medication but endocrine and ultrasound monitoring during the proliferative phase. Ovulation trigger with hCG will be considered when a dominant follicle between 16 and 20 mm will be observed and when the endometrial thickness will be ≥ 6,5 mm. The transfer of a single blastocyst will take place on the 7th day after hCG injection. Serum progesterone levels will be evaluated at four different time points during the day of an artificially prepared frozen embryo transfer cycle (HRT FET cycle) and a modified natural cycle frozen embryo transfer cycle (mNC FET cycle) (at 08:00, 12:00, 16:00 and 20:00). Pairwise percentage differences in serum progesterone levels for each patient will be calculated. The intra-day variability of progesterone will be analyzed using mixed models. Pregnancy outcomes will also be assessed.

Interventions

BIOLOGICALblood test

four blood samples will be withdrawn from the participants during the day of their frozen embryo transfer cycle

Sponsors

Universitair Ziekenhuis Brussel
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
FEMALE
Age
18 Years to 40 Years
Healthy volunteers
No

Inclusion criteria

* Age ≥ 18 and ≤ 40 years old * BMI ≥ 18.5 and ≤ 25,9 kg/m2 * The patient will undergo a hormone replacement therapy frozen embryo transfer cycle (HRT FET) or a modified natural cycle frozen embryo transfer cycle (mNC FET) according to the standard clinical practice in Brussels IVF * In the HRT FET cycle the patient will be administered estradiol valerate and 6 days of micronized vaginal progesterone before the embryo transfer * Adequate endometrial pattern (triple layer) and thickness (\>6.5 mm) at the moment of planning of the transfer * Single blastocyst embryo transfer * Signed informed consent * Non-smokers

Exclusion criteria

* Age \> 40 (women \> 40 years old demonstrated an enhanced rate of absorption of progesterone using vaginal tablets compared to younger patients) * BMI ≥ 26 (serum progesterone levels on the day of embryo transfer are lower in overweight and obese women compared to those with normal weight) * Patients who need to take vaginal estradiol valerate during the HRT FET cycle * Intake of any experimental drug or any participation in any other clinical trial within 30 days prior to study start * Mental disability or any other lack of fitness, in the investigator's opinion, to preclude subjects in or to complete the study. * Current or recent substance abuse, including alcohol and tobacco (patients who stopped tobacco usage at least 3 months prior to screening visit would be allowed) * Refusal or inability to comply with the requirements of the study protocol for any reason, including scheduled clinic visits and laboratory tests. * Embryo transfer after IVM cycle, PGT or oocyte acceptance * Uterine pathologies (fibroids, polyps, chronic endometritis), uterine malformations (septum, Mullerian malformation) and hydrosalpinx

Design outcomes

Primary

MeasureTime frameDescription
The existence of circadian variability of serum progesterone during the day of a frozen embryo transferthe day of the embryo transfer (from 8 am to 8 pm)To evaluate if there is significant variability in circadian level of serum progesterone on the day of an artificially prepared frozen embryo transfer cycle and during the day of a modified natural frozen embryo transfer cycle

Secondary

MeasureTime frameDescription
Pregnancy outcomes after the frozen embryo transferfrom the day of the embryo transfer to 12 weeks of pregnancyTo evaluate the Clinical pregnancy rate (CPR) in patients who underwent HRT FET or mNC FET. CPR is defined as a pregnancy documented by ultrasound at 6-8 gestational weeks that showed a gestational sac in the uterus
The critical progesterone threshold to optimize pregnancy outcomesfrom the day of the embryo transfer to 12 weeks of pregnancyTo evaluate the critical threshold of serum progesterone on the day of the FET below which pregnancy rates are significantly lower
The assessment of serum progesterone on the day of frozen embryo transferthe day of the embryo transfer (from 8 am to 8 pm)To study when is the best moment to measure serum progesterone on the day of FET

Countries

Belgium

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 6, 2026