The prognostic value of HCG, PAPP-A, oestradiol-17 beta and progesterone in early human pregnancy

Association of Low Maternal Pregnancy-associated Plasma Protein A with Adverse Perinatal Outcome

The aim is to provide an overall view of the association of low pregnancy-associated plasma protein A (PAPP-A) levels with adverse perinatal outcomes. The available literature in PubMed/Medline regarding PAPP-A and adverse pregnancy outcomes was searched for related articles, including terms such as “PAPP-A,” “intrauterine growth restriction (IUGR),” “small for gestational age (SGA),” “stillbirth,” “adverse outcome,” and others. The fifth percentile is supported by many recent studies to be PAPP-A’s cutoff for adverse outcome detection and the increased risk seems to be extremely high below 0.2 PAPP-A MoM (multiple of the median). Apart from chromosomal abnormalities, preeclampsia, intrauterine fetal demise, and pregnancy loss have been associated with maternal serum PAPP-A. For results below the first centile, PAPP-A has a strong positive predictive value for SGA and IUGR. Except for its vital role on the cleavage of insulin-like growth factor binding proteins (IGFBP), PAPP-A has proven to be a reliable marker for prenatal screening. Even though PAPP-A as a single predictor proved to be valuable for the prediction of some adverse perinatal outcomes, in some cases, a combination of PAPP-A to other maternal serum markers led to an increase in detection rates. PAPP-A is a promising maternal serum marker for pregnancy outcome prediction with more studies needed in order for its potentials to be fully understood and exploited.

Role of an estradiol regulatory factor-hydroxysteroid dehydrogenase (HSD) in Toxoplasma gondii infection and pathogenicity

Toxoplasma gondii is an apicomplexan parasite that infects most species of warm-blooded animals, including humans, and causes abortions and severe damage to the fetal central nervous system. During pregnancy, the prevalence of toxoplasmosis increases throughout the second and third quarter of gestation, while the hormones progesterone and estradiol simultaneously increase. Thus, it has been suggested that these hormones could affect parasite reproduction. This study was mainly focused on an estradiol regulatory factor-Hydroxysteroid dehydrogenase (HSD) gene in T. gondii. Our data showed that estradiol promoted Pru (Type II) and VEG (Type III) infection and thus significantly contributed to the pathogenicity of T. gondii in mice. Subsequently, we found that this phenomenon may relate to the interplay of T. gondii and estradiol. We reported that estradiol can enter T. gondii tachyzoites. Bioinformatics analysis showed that T. gondii may have a residual estradiol metabolism-related gene HSD. To verify the gene function, HEK293T cells were transiently transfected with Tg-HSD and gene expression was induced. Then, HPLC (high-performance liquid chromatography) analysis showed that Tg-HSD can efficiently transform estrone into estradiol. Moreover, Tg-HSD -overexpressing parasites showed significantly enhanced pathogenicity and upregulation of estradiol levels in mice. In conclusion, estradiol can promote T. gondii infection in vitro and in vivo, and this may be related to its Tg- HSD gene.

Role of serum biomarkers in the prediction of outcome in women with threatened miscarriage: a systematic review and diagnostic accuracy meta-analysis

BACKGROUND

Threatened miscarriage affects one in five women and is associated with significant emotional distress. The uncertainty around the prognosis of threatened miscarriage makes it equally challenging to the healthcare professionals. Various biochemical markers have been investigated in the past to predict the outcome of threatened miscarriage; however, the results have been conflicting. Therefore, we have conducted a systematic review and meta-analysis to determine the diagnostic accuracy of biochemical markers in predicting the outcome in women presenting with threatened miscarriage.

METHODS

This is a systematic review and meta-analysis of prospective studies that investigated biochemical markers to determine outcomes for women with threatened miscarriage at 5-23 weeks gestational age. Electronic databases were searched up to June 2015 and study quality assessment was performed using QUADAS-2 (Quality Assessment for Diagnostic Accuracy Studies-2: A Revised Tool) for evaluating the diagnostic accuracy studies. Statistical analysis was performed using the Cochrane systematic review software.

RESULTS

A total of 19 studies were included in the qualitative data synthesis of which 15 (including 1263 women) were eligible for the meta-analysis. The review highlights the role of biochemical markers serum progesterone, hCG, pregnancy associated plasma protein A, estradiol and cancer antigen 125 (CA 125) in the prediction of outcome in women with threatened miscarriage. Interestingly, serum CA 125 appears to be the most promising marker (n = 648 women in seven studies), whereas serum progesterone and hCG are less useful once fetal viability is established. The summary receiver operating characteristics for CA 125 showed a sensitivity of 90% (95% confidence interval (CI) 83-94%), specificity of 88% (95% CI 79-93%), positive likelihood ratio of 7.86 (95% CI 4.23-14.60) and negative likelihood ratio of 0.10 (95% CI 0.06-0.20). The inverse of negative likelihood ratio was 9.31 (95% CI 5-17.1) indicating that a negative test is likely to identify those who are likely to continue with the pregnancy. Serum estradiol was the next best marker with a sensitivity of 45% (95% CI 6-90%), a specificity of 87% (95% CI 81-92%), a positive likelihood ratio of 3.72 (95% CI 1.01-13.71) and a negative likelihood ratio of 0.62 (95% CI 0.20-1.84).

CONCLUSIONS

In women with threatened miscarriage, serum CA 125 has high predictive value in identifying pregnancies that are 'likely to continue', whereas the most commonly used biomarkers of serum hCG and progesterone are not useful in predicting outcome of a pregnancy with a viable fetus. Other markers such as inhibin A and a combination of markers need to be investigated to hopefully improve the prediction of outcome in women with threatened miscarriage.

Predicting Embryo Presence and Viability

Pregnancy establishment, followed by birth of live offspring, is essential to all mammals. The biological processes leading up to pregnancy establishment, maintenance, and birth are complex and dependent on the coordinated timing of a series of events at the molecular, cellular, and physiological level. The ability to ovulate a competent oocyte, which is capable of undergoing fertilization, is only the initial step in achieving a successful pregnancy. Once fertilization has occurred and early embryonic development is initiated, early pregnancy detection is critical to provide proper prenatal care (humans) or appropriate management (domestic livestock). However, the simple presence of an embryo, early in gestation, does not guarantee the birth of a live offspring. Pregnancy loss (embryonic mortality, spontaneous abortions, etc.) has been well documented in all mammals, especially in humans and domestic livestock species, and is a major cause of reproductive loss. It has been estimated that only about 25-30% of all fertilized oocytes in humans result in birth of a live offspring; however, identifying the embryos that will not survive to parturition has not been an easy task. Therefore, investigators have focused the identification of products in maternal circulation that permit the detection of an embryo and assessment of its well-being. This review will focus on the advances in predicting embryonic presence and viability, in vivo.

Modulation of the endocannabinoid system in viable and non-viable first trimester pregnancies by pregnancy-related hormones

BACKGROUND

In early pregnancy, increased plasma levels of the endocannabinoid anandamide (AEA) are associated with miscarriage through mechanisms that might affect the developing placenta or maternal decidua.

METHODS

In this study, we compare AEA levels in failed and viable pregnancies with the levels of the trophoblastic hormones (beta-human chorionic gonadotrophin (beta-hCG), progesterone (P4) and (pregnancy-associated placental protein-A (PAPP-A)) essential for early pregnancy success and relate that to the expression of the cannabinoid receptors and enzymes that modulate AEA levels.

RESULTS

The median plasma AEA level in non-viable pregnancies (1.48 nM; n = 20) was higher than in viable pregnancies (1.21 nM; n = 25; P = 0.013), as were progesterone and beta-hCG levels (41.0 vs 51.5 ng/mL; P = 0.052 for P4 and 28,650 vs 6,560 mIU/L; P = 0.144 for beta-hCG, respectively, but were not statistically significant). Serum PAPP-A levels in the viable group were approximately 6.8 times lower than those in the non-viable group (1.82 vs 12.25 mg/L; P = 0.071), but again these differences were statistically insignificant. In the spontaneous miscarriage group, significant correlations between P4 and beta-hCG, P4 and PAPP-A and AEA and PAPP-A levels were observed. Simultaneously, immunohistochemical distributions of the two main cannabinoid receptors and the AEA-modifying enzymes, fatty acid amide hydrolase (FAAH) and N-acylphosphatidylethanolamine-phospholipase D (NAPE-PLD), changed within both the decidua and trophoblast.

CONCLUSIONS

The association of higher AEA levels with early pregnancy failure and with beta-hCG and PAPP-A, but not with progesterone concentrations suggest that plasma AEA levels and pregnancy failure are linked via a mechanism that may involve trophoblastic beta-hCG, and PAPP-A, but not, progesterone production. Although the trophoblast, decidua and embryo contain receptors for AEA, the main AEA target in early pregnancy failure remains unknown.

Nuchal translucency as a predictor of adverse pregnancy outcome

BACKGROUND

Thickened nuchal translucency (NT) has been related to fetal genetic syndromes, structural abnormalities, and other diseases. The aim of this research was to evaluate the association of NT with adverse pregnancy outcomes.

STUDY DESIGN

In the period 2002-2004 in 2104 pregnant women between 10+6 and 13+5 weeks' gestation, NT was evaluated as a parameter for aneuploidy screening: out of these, 734 singleton pregnant women that underwent 2nd trimester amniocentesis and whose pregnancy outcome were known were selected. NT was statistically correlated to pregnancy and neonatal outcome.

RESULTS

Median gestational age (GA) at NT evaluation was 11+2 weeks' gestation. NT median was 1.1 mm (0.9-1.4 mm, 25th-75th centile, range 0.5-4.0 mm). After multiple logistic regressions, the variables significantly associated to NT values were: threatened preterm labor (p<0.008) and preterm labor (p<0.02). The best diagnostic accuracy point was NT>95th centile and >1.5 MoM for the prediction of threatened preterm labor.

CONCLUSION

In this series, increased NT values were associated to threatened preterm labor and preterm labor in euploid fetuses: this finding may have clinical consequences in the management of such pregnancies.

Decreased first trimester PAPP-A is a predictor of adverse pregnancy outcome

OBJECTIVE

Low levels of maternal serum pregnancy associated plasma protein-A (PAPP-A) have been linked to chromosome anomalies such as trisomy 21, 13 and 18, triploidy and sex chromosome aneuploidy. Low levels of PAPP-A have also been implicated in spontaneous miscarriage. The purpose of this study was to evaluate whether low levels of first trimester PAPP-A are predictive of other adverse pregnancy outcomes.

STUDY DESIGN

The study included patients with singleton pregnancies who underwent combined first trimester screening using nuchal translucency (NT) and maternal serum free beta-human chorionic gonadotrophin (free beta-hCG) and PAPP-A at 10-13 weeks' gestation. Patients with chromosome aberrations or fetal anomalies were excluded. Serum marker levels were expressed as gestational age-specific multiples of the median (MoMs). The incidences of various adverse pregnancy outcomes (spontaneous preterm labor, fetal growth restriction (FGR), proteinuric and non-proteinuric pregnancy induced hypertension (PIH), intrauterine fetal demise, oligohydramnios, spontaneous miscarriage and placental abruption) were evaluated, according to maternal PAPP-A MoM levels.

RESULTS

Of the 1622 patients in the study, pregnancy complications were observed in 184 (11.3%). Patients with PAPP-A < or =0.25 MoM had significantly higher rates of FGR (RR = 3.12), proteinuric PIH (RR = 6.09), spontaneous miscarriage (RR = 8.76). No statistically significant differences were noted for other adverse outcomes evaluated Women with PAPP-A < or =0.50 MoM also had significantly higher rates of FGR (RR = 3.30) and spontaneous miscarriage (RR = 3.78).

CONCLUSIONS

We conclude that decreased levels of first trimester maternal serum PAPP-A are predictive not only of chromosome anomalies but also of adverse pregnancy outcome.

Luteal phase hormonal profile in prediction of pregnancy outcome after assisted reproduction

The clinical efficacy of luteal phase hormones including estradiol and progesterone in the prediction of pregnancy and its outcome in ICSI-ET cycles was evaluated. In 121 ICSI-ET cycles, serial estradiol and progesterone levels were measured in the luteal phase. The day of ovum pick-up was designated as day 0. All the patients had luteal support with vaginal progesterone suppositories after embryo transfer (ET). Serial estradiol measurements were performed on days 8, 11 and 13 and progesterone level on day 11. A single dose of hCG was given for corpus luteum rescue 5000 IU, if day 8 estradiol level <200pg/ml; 2000IU, if estradiol between 200 and 800pg/ml; no hCG if estradiol level >800pg/ml). On day 15, beta-hCG level was measured to detect pregnancy and if positive, injected on day 17. Fifty-seven pregnancies were achieved in 121 cases after ET (47%). Clinical pregnancy rate and ongoing pregnancy rate per ET were 37.1 and 30%, respectively. While there was no difference between progesterone levels measured on day 11, estradiol levels on days 11 and 13 were significantly higher in women who became pregnant. In 40 patients taking only progesterone and in 81 cases taking hCG plus progesterone, estradiol levels on days 11 and 13 were significantly higher in women who became pregnant. Progesterone levels on day 11, in progesterone treated groups, did not differ between pregnant and non-pregnant patients. Estradiol and progesterone levels on day 11 and estradiol levels on day 13 showed a big overlap between pregnant and non-pregnant patients. The efficacy of serial testing was evaluated. An increase in estradiol level from day 11 to 13 was associated with 71% pregnancy rate (72% ongoing). In the case of a decrease in estradiol level, the pregnancy rate was 18% of which 80% had to implant. Rising estradiol in the late luteal phase is associated with higher pregnancy rate and more successful pregnancy outcome.

The prognostic value of serum estradiol, progesterone, testosterone and free testosterone levels in detecting early abortions

OBJECTIVE

Hormonal levels in early pregnancy may have predictive value in regard to outcome of pregnancy. In this study, the levels of estradiol (E2), progesterone (P), total testosterone (tT) and free testosterone (fT) were investigated in this respect.

MATERIALS AND METHOD

Seventy women with early pregnancies of 6-12 weeks who applied to the hospital for a pregnancy test were included into this study and were divided into three groups according to their final diagnosis. Group 1 consisted of 20 patients with anembryonic pregnancies, group 2 consisted of 20 patients with missed abortion and group 3 had 30 patients with normal pregnancies. Serum levels of E2, P, fT and tT were measured in every patient and the ratio of fT to tT was calculated (fT ratio).

RESULTS

E2, P and tT levels in patients with missed abortion or anembryonic pregnancies were significantly lower than those in the normal group, whereas fT ratio was significantly higher. The level of P over 12.3 ng/ml was found to be sensitive and specific with respect to detecting a normal pregnancy (95% and 90%, respectively). All patients whose fT ratios were 1.05 and higher, subsequently miscarried whereas the ones whose fT ratios were lower than 0.84 were considered as normal pregnancies.

CONCLUSION

Serum P levels and fT ratio in early pregnancies can be used as a screening test with high sensitivity and specificity to predict a normal pregnancy.

Trophoblast antigen levels in the first trimester of a trisomy 22 pregnancy

We report trophoblast antigen (pregnancy-associated plasma protein-A, PAPP-A; free beta-human chorionic gonadotrophin, F beta hCG) expression in a trimosy 22 pregnancy. Maternal concentrations of these antigens were depressed prior to detection of abnormalities by ultrasonography. Immunohistochemical findings were consistent with depressed marker expression.

Free testosterone and abortion in early pregnancy

OBJECTIVES

To investigate the relationship between percentage of free testosterone (% free T) and the abortion rate in early pregnancy.

METHODS

Progesterone (P), estradiol (E2), total T, sex hormone binding globulin (SHBG), and % free T were measured in sera obtained from 60 pregnant women with normal pregnancy (n = 38) and missed abortion (n = 22) at between 4 and 12 weeks' gestation.

RESULTS

P, E2, total T, and SHBG in 22 patients with missed abortion were significantly lower than those in normal group, whereas % free T was significantly higher. There was a significant negative correlation between % free T and SHBG concentration in the normal group, but not in the missed abortion group. All the subjects in whom % free T was 1.30% and higher subsequently miscarried, but no subject with % free T less than 0.70% had a miscarriage.

CONCLUSIONS

The lower the % free T, the lower the rate of subsequent abortion. The value of % free T may be able to predict pregnancy outcome in early pregnancy.

Chromosome abnormalities detected in chorionic villus biopsies of failing pregnancies in a subfertile population

OBJECTIVE

To determine the range and prevalence of chromosomal abnormalities occurring in failing pregnancies in subfertile women.

DESIGN

Prospective biochemical and ultrasound monitoring of all pregnancies conceived between 1988 and 1990 in a subfertile population.

SETTING

A single-centre specialist fertility clinic in Perth, Western Australia.

SUBJECTS

Tissue from 50 early pregnancy losses was successfully cultured for chromosomal analysis from 46 pregnancies comprising 29 anembryonic pregnancies, 9 miscarriages and 8 ectopic pregnancies.

MAIN OUTCOME MEASURES

Impending pregnancy loss was identified at an early stage. Chromosomal analysis was performed on chorionic villi obtained before the diagnosis became clinically evident.

RESULTS

Significant chromosomal abnormalities were identified in 54% (14/26) of early pregnancy losses where gamete manipulation was involved and 45% (9/20) of those following spontaneous conception. The most common abnormalities were trisomies (12 pregnancies, mainly trisomy 16), triploidies (3 pregnancies) and monosomy X (3 pregnancies). An excess of female fetuses was noted with only 24% of conceptuses (11/46) bearing a Y chromosome.

CONCLUSIONS

The data indicate a similar rate of chromosomal abnormalities underlying pregnancy losses at earlier stages of pregnancy and after infertility treatments as that reported from the general population. Gamete manipulation does not appear to confer a higher rate of chromosomal abnormalities in ensuing pregnancies.

Late luteal estradiol patterns are a better prognosticator of pregnancy outcome than serial beta-human chorionic gonadotropin concentrations

OBJECTIVE

Since the corpus luteum (CL) is known to play an important role in early pregnancy, its activity could possibly be a marker for pregnancy outcome.

DESIGN

The late estradiol (E2) concentration in 48 viable pregnancies and 39 pregnancies which resulted in spontaneous abortions after in vitro fertilization and embryo transfer were used to evaluate such predictability.

SETTING

All patients studied were of the Center for Reproductive Medicine at Cornell University Medical College.

PATIENTS, PARTICIPANTS

Eighty-seven patients.

INTERVENTIONS

None.

MAIN OUTCOME MEASURE

Serum E2 and human chorionic gonadotropin (hCG) concentrations on day +11, +13, +15 (day +1 = day of ovum pick-up) were measured and studied.

RESULTS

The late luteal CL activity after rescue had a positive correlation with the number and quality of the implanted embryos. Reduced CL activity was indicative of abortion. The late luteal E2 pattern when compared with hCG doubling time had a better abortion predictability (37.8% versus 63.9%, respectively).

CONCLUSION

Corpus luteum activity demonstrated to be a better prognosticator of abortion than serial beta-hCG titers.

Early pregnancy wastage in IVF (in vitro fertilization) patients

Human in vitro fertilization is characterized by a low efficiency of implantation. Possible mechanisms for pregnancy loss are discussed. Embryo viability or quality, abnormal implantation, and delayed or absent corpus luteum rescue may all play a role in pregnancy wastage. Defining the possible mechanism for these losses may allow hormonal treatment to correct specific abnormalities.

Comparison of maternal serum estradiol and progesterone levels in pregnancies after induced and spontaneous ovulation

Maternal serum estradiol and progesterone levels during the early 6th to 15th weeks of gestation, were measured by radioimmunoassay in 140 pregnancies following induction of ovulation with gonadotropins or clomiphene citrate. The levels were compared with those observed in 79 spontaneous pregnancies. Significantly higher levels were observed in gonadotropin and clomiphene citrate induced pregnancies (both P values less than 0.001) between the 6th to 9th week of gestation as compared to spontaneous pregnancies. Steroid levels were similar in the two groups from the 9th week onwards. No statistically significant differences in steroid hormone values were observed in aborted and successful pregnancies within each group studied. We conclude that ovulation induction is associated with higher estradiol and progesterone levels until placental steroidogenesis starts.

Ultrasound and circulating placental protein measurements in complications of early pregnancy

Maternal serum levels of human chorionic gonadotrophin (hCG), Schwangerschaftsprotein 1 (SP1) and pregnancy-associated plasma protein A (PAPP-A) were measured in an unselected group of 624 women presenting with amenorrhoea and vaginal bleeding with or without abdominal pain to an emergency gynaecological ultrasound clinic. Abdominal sector scanning was used to assess uterine contents. Pregnancy was confirmed by ultrasound in 406 pregnancies. Histological confirmation was obtained in each case of pregnancy failure. A live fetus was demonstrated in 259 women of whom six subsequently miscarried; one of these had markedly depressed serum hCG and PAPP-A, but normal SP1 levels, and two had oligohydramnios. Of the 147 women without ultrasound evidence of fetal heart action 67 had a correct ultrasound diagnosis of anembryonic pregnancy. The predictive value of a depressed serum hCG level was 70% in this group, and 31% in samples taken at less than or equal to 7 weeks. The predictive value of a normal hCG level was 96%. In 34 women missed miscarriage was diagnosed readily by ultrasound; all but five had depressed hCG and PAPP-A levels. A clinical diagnosis of a complete or incomplete miscarriage was made in 45 women and easily confirmed by ultrasound. All of them had depressed hCG, SP1 and PAPP-A levels. These results indicate that the diagnostic value of ultrasound in threatened miscarriage is often better than that of biochemical tests.

Some endocrinological events associated with early pregnancy failure

Serial measurements of serum progesterone, oestradiol, human chorionic gonadotrophin (hCG) and human placental lactogen (hPL) have been determined in 33 women experiencing early pregnancy failure and compared with the values of the same hormones in 72 healthy women having uncomplicated pregnancies. Steroid production by the corpus luteum seemed similar in both groups up to 6 weeks gestation but thereafter placental steroidogenesis was not evident in those women in whom spontaneous pregnancy losses occurred. Placental production of the two protein hormones, hCG and hPL, did take place, and whereas the circulating levels were not as high as in normal pregnancies, levels did usually increase before clinical evidence of miscarriage occurred. hCG was not a sensitive discriminator of subsequent failure. In these women there were no significant hormone differences between those with evidence of a fetus and those without.

Early pregnancy wastage after gamete manipulation

The outcome of 1034 pregnancies in women who conceived after referral for infertility management in seven treatment groups is detailed. The mean early pregnancy wastage (before 20 weeks gestation) was 27% and ranged from 18% after AID (artificial insemination by donor semen) to 33% after IVF-ET (in-vitro fertilization and embryo transfer). These differences were not due to maternal age which was similar in all groups (means between 29.7 and 32.7 years). Excluding the AID group, there was a high rate of ectopic pregnancy which was significantly higher after GIFT (gamete intrafallopian transfer) and was only partly related to underlying tubal disease. Blighted ova was the main category of early pregnancy loss and was highest after AIH (artificial insemination by husband's semen). There was a higher rate of biochemical pregnancies after GIFT, PROST (pronuclear stage tubal transfer) and IVF-ET. Our findings confirm a high pregnancy wastage rate in subfertile women and highlight deficiencies in the sperm separation, gamete handling and IVF/embryo culture techniques.

Medroxyprogesterone acetate therapy in early pregnancy has no apparent fetal effects

Medroxyprogesterone acetate (MPA; Provera) was given orally to 449 women from the 5th to 7th week of pregnancy until at least the 18th week. Data are recorded from two treatment groups (recurrent abortion and threatened abortion) and are compared to a matched series. A total of 1,016 pregnancies are included in the study, and all patients were recruited from a subfertile population conceiving from a range of infertility treatments. Early pregnancy wastage was high throughout the groups and was significantly elevated (43%; P less than .001) in those women who had vaginal bleeding in early pregnancy. The study focuses on the question of potential teratogenicity of progestagens administered in the first trimester. There were 15/366 (4.1%) infants with congenital abnormalities in the MPA-treated group and 15/428 in the untreated group (3.5%). The difference was not significant, and MPA is considered to have no embryopathic risk, nor is it likely to retain an abnormal fetus that might otherwise abort. It appears that MPA is a safe drug to use in pregnancy although the question of efficacy has not been addressed in this report. Considering other recent negative epidemiologic studies with regard to teratogenicity, we add to the conclusion that MPA cannot be demonstrated to have a measurable teratogenic risk and certainly does not present a risk for congenital heart disease and limb reduction defects.

Beta-human chorionic gonadotropin as a monitor of pregnancy outcome in in vitro fertilization-embryo transfer patients

Serum human chorionic gonadotropin (hCG) was studied to test its predictability of pregnancy outcome in in vitro fertilization (IVF) patients. The mean +/- standard deviation of serum hCG concentration related to the day complete clearance of exogenous hCG was derived from 47 single term pregnancies as a normal range. This range can be used to predict spontaneous abortion (77%), multiple pregnancy (60%), and abortion in multiple-sac pregnancies terminating in the birth of fewer infants than the initial number of sacs (80%). The results also showed that our stimulation protocol did not affect the clearance rate and doubling time of endogenous hCG or implantation time as suggested by the time of endogenous hCG detection and that spontaneous abortion may be due to late implantation.

Mechanisms and factors of early pregnancy wastage in in vitro fertilization-embryo transfer patients

Although the pregnancy rate per transfer of the Norfolk In Vitro Fertilization-Embryo Transfer (IVF-ET) program has been reported as between 25% and 35%, the viable pregnancy rate per transfer is only 15% to 20%. An understanding of the mechanism(s) and etiologic factors of miscarriage among IVF patients might suggest changes that could prevent some early pregnancy wastage. Forty-seven consecutive single pregnancies and 26 miscarriages (October 1985 to November 1986) were included in this study. Factors such as implantation time, date of corpus luteum rescue (CLR), embryo quality, and corpus luteum activity after rescue were studied and compared between term pregnancy and miscarriage groups. Results are discussed in detail in this paper.