The following is a summary of “Circadian serum progesterone variations on the day of frozen embryo transfer in artificially prepared cycles,” published in the January 2024 issue of Obstetrics & Gynecology by Loreti, et al.

What changes happen during the day in blood progesterone when progesterone is given vaginally on the day of a frozen embryo transfer (FET) in a fake cycle? From August to December 2022, 22 patients who had a single embryo artificial cycle (AC)–FET were part of a prospective cohort study. Endometrial preparation was done by giving oestradiol valerate (2 mg three times a day) and then micronized vaginal progesterone (MVP; 400 mg twice a day). It was decided to do a blastocyst FET on the sixth day of giving MVP. On the day of the transfer, levels of progesterone in the blood were checked at 8:00, 12:00, 16:00, and 20:00. Just before MVP was given, the first and last blood samples were taken.

The study participants were 33.95 years old, 3.98 years old on average, and 23.10 kg/m² on average. It was 11.72 ± 4.99 ng/ml on average at 8:00, 13.59 ± 6.33 ng/ml at 12:00, 10.23 ± 3.81 ng/ml at 16:00, and 9.28 ± 3.09 ng/ml at 20:00. Between the first and last progesterone tests, there was a big drop of 2.41 ng/ml (95% CI: 0.81–4.00).

There was a statistically significant change in blood progesterone levels during the day of FET in rounds that were made in a lab. It showed how important it is to have a regular way to measure progesterone at the right time on the day of the AC–FET. It’s important to note that the study results only apply to women who use MVP for luteal phase support. Because of this, it’s necessary to prove their truth by comparing them to the different ways that progesterone is currently given.

Source: sciencedirect.com/science/article/abs/pii/S1472648323007009