Rescue of the Corpus Luteum in Human Pregnancy1

Abstract

Rescue of the corpus luteum from its programmed senescence maintains progesterone production required for pregnancy. In primates, chorionic gonadotropin produced by the developing conceptus acts as the primary luteotrophic signal. The purpose of this research was to assess corpus luteum rescue by examining changes in daily urinary progesterone metabolite levels during the first week after implantation. We determined the variability in progesterone metabolite profiles and evaluated its relationship to early pregnancy loss in 120 naturally conceived human pregnancies, including 43 early pregnancy losses. In other primates, an abrupt increase in the progesterone metabolite occurs at the time of implantation. This pattern occurred in an estimated 45% of the pregnancies in the present study. In the remaining pregnancies, there was a delayed rise (18%), neither a rise or decline (22%), or a decline (15%) during the week after implantation. The estimated rate of early pregnancy loss increased across these categories (from 5% loss with an abrupt rise at implantation to 100% loss with progesterone metabolite decline). Low urinary hCG levels in early pregnancy were significant determinants of a decline in postimplantation progesterone metabolite. However, preimplantation steroid metabolite levels were not significant, suggesting no inherent problem with the corpus luteum. Examination of individual progesterone metabolite profiles in relation to hCG profiles also indicated that few losses were caused by corpus luteum failure. Delineating the functional importance of an abrupt progesterone rise at the time of implantation may provide new strategies for promoting successful implantation in assisted reproduction. corpus luteum, corpus luteum function, human chorionic gonadotropin, pregnancy, progesterone

A non-hormonal model for emergency contraception: prostaglandin synthesis inhibitor effects on luteal function and lifespan, a pilot study

“…However, we did not find a shorter menstrual cycle with daily administration of a PTGS2 but a trend towards a longer menstrual cycle with either a delay in the rise or no rise in luteal phase P levels. Collectively, these findings support the hypothesis that prostaglandin synthesis is critical for luteal development [4][5][6][7][8][9][10][11]. Unfortunately, our study design did not allow us to discriminate if its action was pre-ovulatory, post-ovulatory, or both.…”

“…Prostaglandins have been shown to play a critical role in ovulation as well as the formation and/or maintenance of the corpus luteum [4][5][6][7][8][9][10][11]. Thus, inhibition of their synthesis or action may serve as an effective contraceptive prior to and after fertilization by blocking ovulation and implantation, respectively.…”

Alteration of Human Chorionic Gonadotropin Levels among Pregnant Women with Morning Sickness Attending Antenatal Care Services at Ishaka Adventist Hospital, Uganda

“…hCG is produced in the earliest stages of pregnancy. During early pregnancy it plays a role in survival of the corpus luteum [10] and in stimulating the thyroid gland [11], and it also appears to have a significant role in the implantation of the blastocyst and protection of the embryo against immune attack at the fetal-maternal boundary. The hormone is initially produced by the embryo and, therefore, also acts as a marker for its presence [12].…”

Increased Day 15–17 Serum Pro-αC Inhibin Levels Specific to Successful Pregnancy

“…There were nine patients who had a frozen ET of whom we were unsure of the regimen. Tong Table 4 shows the levels of hCG and progesterone levels at d [15][16][17]. Correlations between analytes were limited to those cases where a clinical pregnancy eventuated.…”