Serum anti-müllerian hormone (AMH) concentration during pregnancy: a longitudinal study.

A prospective longitudinal cohort study aimed to longitudinally examine the kinetics of Anti-müllerian hormone (AMH) during the first two trimesters of pregnancy. Pregnant women with stored 1st trimester serum samples were recruited at 24-28 weeks gestation during their gestational diabetes testing, where they provided an additional serum sample. The samples were analysed for AMH, oestradiol and progesterone concentrations.

Is there an optimal window of time for transferring single frozen-thawed euploid blastocysts? A cohort study of 1170 embryo transfers.

Study Question: Is there an optimal window of time when the transfer of single frozen-thawed euploid blastocysts is associated with a maximal live birth rate (LBR)?

Summary Answer: Performing a single frozen-thawed euploid blastocyst transfer at 160 ± 4 h post-hCG trigger in modified-natural frozen-thawed embryo transfer (FET) cycles was independently associated with a higher LBR as compared to transfers outside this window; however, in natural FET cycles, LBRs were comparable across a wider range of time intervals.

What Is Known Already: There is compelling evidence for maintaining embryo-endometrial synchrony to optimize clinical outcomes following FETs, which could potentially be achieved by matching the transfer time of an embryo post-ovulation to its developmental age post-oocyte retrieval. For modified-natural cycles, ovulation is widely accepted to occur ∼40 h following the hCG trigger, whilst ovulation following spontaneous LH surge onset is thought to vary from 24 to 56 h.