The rate at which serum total beta-subunit human chorionic gonadotropin increases after embryo transfer is a predictor of the viability of pregnancy and an identifier of determinants of pregnancy

Pregnancy complications and placental histology in in vitro fertilization pregnancies with initial low serum β-hCG levels

OBJECTIVE

To assess perinatal outcomes and placental findings after in vitro fertilization (IVF) with an initial low serum β-human chorionic gonadotropin (hCG).

DESIGN

A retrospective cohort study.

SETTING

University-affiliated tertiary hospital.

INTERVENTION(S)

Low serum β-hCG after transfer, defined as the low 10th percentile for the cohort on day 16 embryo age (low β-hCG group), compared with an initial serum β-hCG at or above the low 10th percentile (control group).

PATIENT(S)

Live singleton births after IVF between 2009 and 2017.

MAIN OUTCOME MEASURE(S)

Primary outcomes were placental findings, including anatomic, inflammatory, vascular malperfusion, and villous maturation lesions, as categorized according to the Amsterdam Placental Workshop Group Consensus. Secondary outcomes included obstetric and perinatal outcomes.

RESULT(S)

The low 10th percentile of β-hCG results corresponded to 149 mUI/mL. There were 103 cases in the low β-hCG group, and 928 in the control group. Maternal demographics were similar between the groups, whereas blastocyte transfer was more common in the control group. Deliveries in the low β-hCG group were associated with an increased rate of preterm births, 15.5% vs. 8.1%, which maintained significance after adjustment for confounders. Placentas in the low β-hCG group were notable for a high rate of velamentous cord insertion, 19.4% vs. 7.7%, single umbilical artery 3.8% vs. 0.6%, and histological maternal vasculopathy, 10.6% vs. 4.8%.

CONCLUSION

Live births after IVF with an initial low β-hCG level are associated with a twofold increase in preterm births and placental gross and histological changes. It may thus be considered to observe such cases in a high-risk pregnancy setting.

Possibility of live birth in patients with low serum β-hCG 14 days after blastocyst transfer

Background

Although prior work has attempted to predict pregnancy outcomes by assaying serum β-hCG levels after blastocyst transfer, no study has focused on pregnancy outcomes in those with initially low serum β-hCG levels. This study sought to investigate pregnancy outcomes of patients with low serum β-hCG levels 14 days after blastocyst transfer.

Methods

A retrospective study was conducted at the Third Affiliated Hospital of Guangzhou Medical University to study patients whose serum β-hCG levels were at 5–299 mIU/ml 14 days after frozen blastocyst transfer. Rates of live birth, early miscarriage, biochemical pregnancy loss and ectopic pregnancy were analyzed according to the female patients’ age by Chi-squared analysis. Receiver operating characteristic (ROC) curves were plotted to explore the threshold of predicting clinical pregnancy and live births.

Results

312 patients had serum β-hCG levels < 300 mIU/ml at 14 days after frozen blastocyst transfer, among which, 18.6% were live births, 47.4% were early miscarriages, 22.8% were biochemical pregnancies and 9.6% were ectopic pregnancies. ROC curve analysis showed that a predicted value of β-hCG for clinical pregnancy was 58.8 mIU/ml with an area under the ROC curve (AUC) of 0.752, a sensitivity of 95.0% and specificity of 53.5%. The threshold for live births was 108.6 mIU/ml with an AUC of 0.649, a sensitivity of 93.1% and a specificity of 37.0%. For the β-hCG fold increase over 48 h, the cut-off for clinical pregnancy was 1.4 with an AUC of 0.899, a sensitivity of 90.3% and a specificity of 77.8%. The threshold for live birth was 1.9 with an AUC of 0.808, a sensitivity of 88.5% and specificity of 64.5%.

Conclusions

Initially low serum β-hCG levels 14 days after frozen blastocyst transfer indicated minimal chances of live birth. For patients having an initial β-hCG > 58.8 mIU/ml, luteal phase support should continue. Another serum β-hCG test and ultrasound should be performed one week later. When an initial serum β-hCG is < 58.8 mIU/ml, luteal phase support should be discontinued and serum β-hCG measured with ultrasound one week later.

Trends in primeval β-hCG level increment after fresh and frozen-thawed IVF embryo transfer cycles

Mid-trimester beta-human chorionic gonadotropin (BHCG) levels are considerably higher in pregnancies resulting from frozen embryo transfer (FET) compared with fresh (FRET), leading to a higher false positive rate in aneuploidy screening tests. We aimed to investigate the dynamics of BHCG increment and its predictive value for cycle outcome. A retrospective analysis of FRET and FET cycles. BHCG values on days 14 and 16 post embryo transfer were compared and stratified according to the number of sacs demonstrated on US scan at six weeks gestation, and pregnancy outcome (biochemical pregnancy, ectopic pregnancy, spontaneous abortion, and a singleton or twin birth). A prediction model for live birth was built. A total of 430 treatment cycles were analyzed. The average BHCG levels were significantly higher in FET compared with FRET group in nonviable pregnancies on day 14, 450 vs. 183 IU/L, p < .05 and day 16, 348 vs. 735 IU/L, p < .05, respectively. The increment of BHCG was significantly steeper in the FET compared with FRET group in biochemical pregnancies (F = 6.485, p = .012*). Optimal cutoff level for live birth prediction in the FRET group was 211 IU/L (sensitivity 84%, specificity 76.2%) for day 14 and 440 IU/L (sensitivity 86.0% and specificity 72.5%) for day 16. The increment in BHCG differed significantly between the FRET and FET cycles in nonviable pregnancies. Nevertheless, the difference in BHCG levels observed in the second trimester in pregnancies conceived after FRET and FET cycle may begin as early as the fourth week of pregnancy.

Serum human chorionic gonadotropin measured 7 days following day 3 embryo transfer might predict pregnancy outcome in IVF

This prospective study investigated the predictive value of pregnancy outcomes with serum human chorionic gonadotropin (hCG) 7 days after day 3 embryo transfer (D3 ET), and whether estradiol (E2) and progesterone (P) improved the diagnostic efficiency. The study comprised 280 in vitro fertilization and embryo transfer (IVF-ET) cycles. Serum samples were obtained 7 days after D3 ET to measure hCG, E2, and P concentrations. Statistical analyses were conducted to evaluate the predictive value for pregnancy outcomes. We found significant differences in hCG level between pregnancy and non-pregnancy, viable and non-viable pregnancy, biochemical and viable pregnancy, as well as singleton and multiple pregnancy. An hCG cutoff value of 2.5 mIU/mL is predictive of pregnancy with a positive predictive value (PPV) of 95.9% and a negative predictive value (NPV) of 92.4%. An hCG value of 10.8 mIU/mL is predictive of a multiple pregnancy with an NPV of 98.1%. The area under the hCG curve between pregnancy and non-pregnancy was not improved by adding E2, P, or combined E2/P. Our results suggest a predictive value of pregnancy outcome with serum hCG drawn 7 days after D3 ET in IVF, and the diagnostic accuracy is not improved by adding measurements of E2/P.

Serum hCG-β levels of postovulatory day 12 and 14 with the sequential application of hCG-β fold change significantly increased predictability of pregnancy outcome after IVF-ET cycle

PURPOSE

To investigate hCG-β level on postovulatory day (POD) 12 and its fold increase as predictors for pregnancy outcome after in vitro fertilization (IVF) cycles.

METHODS

A retrospective cohort study was performed in total 1408 fresh and 598 frozen cycles between November 2008 and October 2011, which resulted in biochemical pregnancy, early pregnancy loss, or live birth of singleton pregnancy. The serum hCG-β levels of POD 12 and 14 were compared among biochemical pregnancy, early pregnancy loss, and live birth groups. The cutoff values of POD 12 and 14 hCG-β levels and the degree of hCG-β increase from POD 12 to 14 were determined for each pregnancy outcome.

RESULTS

POD 12 and 14 hCG-β levels stratified based on pregnancy outcomes were significantly different among the biochemical pregnancy, early pregnancy loss, and live birth in both fresh and frozen cycles. Serum hCG-β levels of POD 12 and 14 and the fold increase of hCG-β levels from POD 12 to 14 significantly predict pregnancy outcomes after fresh and frozen cycles. Among these, the cutoff value of POD 14 hCG-β had the highest sensitivity and positive predictive value (PPV). In fresh cycles, the cutoff values of POD 12 and 14 serum hCG-β levels for clinical pregnancies were 30.2 mIU/mL (sensitivity 81.3 %, specificity 79.6 %, and PPV 92.3 %) and 70.5 mIU/mL (sensitivity 88.4 %, specificity 85.2 %, and PPV 94.7 %). In pregnancies with POD 12 serum hCG-β levels ≥30.2 mIU/mL, the cutoff level of increase of hCG-β for clinical pregnancy was 2.56 (sensitivity 73.6 %, specificity 72.4 %, and PPV 97.8 %). Sequential application of cutoff values such as POD 12 hCG-β and fold increase of hCG-β improved predictability of pregnancy outcome as compared with that of POD 12 hCG-β alone. The cutoff values of POD 12 and 14 serum hCG-β levels for live birth were 40.5 mIU/mL (sensitivity 75.2 %, specificity 72.6 %, PPV 78.9 %) and 104.5 mIU/mL (sensitivity 80.3 %, specificity 74.1 %, PPV 80.8 %). In the frozen cycles, the cutoff values of POD 12 and 14 serum hCG-β level for clinical pregnancy were 31.5 IU/L (sensitivity 80.4 %, specificity 71.1 % and PPV 90 %) and 43.5 mIU/mL (sensitivity 72.6 %, specificity 71.7 %, PPV 77.2 %). In pregnancies with POD 12 serum hCG-β level ≥31.5 mIU/mL, the cutoff value for fold increase of hCG-β was 2.38 for clinical pregnancy (sensitivity 81.6 %, specificity 71.4 % and PPV 87.9 %). The cutoff values of POD 12 and 14 for live birth were 43.5 mIU/mL (sensitivity 72.6 %, specificity 71.7 %, PPV 77.2 %) and 101.6 mIU/mL (sensitivity 79.6 %, specificity 71.1 %, PPV 78.4 %). Sequential application of cutoff values for POD 12 hCG-β level and fold increase of hCG-β significantly increased PPV for live birth but not clinical pregnancy in frozen cycles.

CONCLUSIONS

Early prediction of pregnancy outcome by using POD 12 and 14 cutoff levels and sequential application of cutoff value of fold increase could provide appropriate reference to health care providers to initiate earlier management of high-risk pregnancies and precise follow-up of abnormal pregnancies.

Association of the very early rise of human chorionic gonadotropin with adverse outcomes in singleton pregnancies after in vitro fertilization

OBJECTIVE

To determine if very early serum hCG, a marker of trophoblast differentiation, is associated with adverse perinatal outcomes in singleton pregnancies.

DESIGN

Retrospective cohort study.

SETTING

University fertility program.

PATIENT(S)

A total of 360 singleton IVF live births.

INTERVENTION(S)

Serial hCG measurements were used to determine the within-woman slope for hCG (hCG rise).

MAIN OUTCOMES MEASURE(S)

Primary outcomes included birth weight and gestational age at delivery. Statistical comparisons used t test, chi-square test, and linear and logistic regressions as appropriate.

RESULT(S)

hCG rise was positively associated with birth weight but not gestational age at delivery. Infant sex, gestational age, and type of embryo transfer (fresh vs. frozen/thawed) were significantly associated with birth weight and confounded the associations of interest. hCG rise was slower among subjects delivering an infant with low birth weight (slope 0.386 ± 0.05 vs. 0.407 ± 0.06) or small for gestational age (slope 0.371 ± 0.07 vs. 0.406 ± 0.06). Analysis of hCG rise by quartile showed that, compared with the first quartile (slowest), subjects with a rate of hCG rise in the fourth quartile (fastest) had a significantly decreased risk of delivering an infant of low birth weight. No relationship was noted between hCG rise and hypertensive disorders of pregnancy.

CONCLUSION(S)

Slower very early first-trimester hCG rise is associated with low birth weight but not gestational age at delivery among singleton IVF conceptions. The rate of increase in serum hCG may reflect early trophoblast differentiation and placentation and, possibly, may predict subsequent development.

Effect of vitrification versus slow freezing of human day 3 embryos on β-hCG levels

PURPOSE

The study was designed to investigate the effect of vitrification and slow freezing for the cryopreservation of human day 3 embryos on serum β-hCG levels in pregnancies established after frozen embryo transfer (FET).

METHODS

Of the 1384 FET cycles initiated, 1131 embryo transfers met study criteria and assigned to one of two groups: 797 slow-freezing embryo transfers or 334 vitrified embryo transfers. Median values of β-hCG and outcome of all pregnancies were compared between the two groups. Predictive values of serum β-hCG on day 12 after embryo transfer for establishing ongoing pregnancy and pregnancy failure were determined by receiver operating characteristic (ROC) curve analysis.

RESULTS

In the slow-freezing group, 383 ongoing pregnancies occurred (48.1 %), and transfers of vitrified embryos resulted in 154 pregnancies (46.1 %). Median β-hCG values (279.2 IU/L) for ongoing pregnancies after transfer of vitrified embryos were significantly lower than that of slow frozen embryos (320.5 IU/L). The median values of β-hCG for singleton in the two groups was statistically significant (P <0.05). For slow-freezing embryo transfers, the cut-off value of β-hCG in predicting ongoing pregnancy was 147 IU/L (sensitivity 88.3 %, specificity 80.7 %). For vitrified embryo transfers, the value was 135 IU/L (sensitivity 84.4 %, specificity 76.3 %).

CONCLUSIONS

Day 12 β-hCG levels after FET are significantly affected by the methods of embryo cryopreservation for ongoing pregnancies. Furthermore, when using β-hCG cut-off value to assess pregnancy outcome, the cryopreservation methods should be taken into account.

The association of maternal factors with delayed implantation and the initial rise of urinary human chorionic gonadotrophin

BACKGROUND Late implantation and the pattern of early rise in hCG have been associated with early pregnancy loss. We explored factors that might be predictive of these markers of poor embryonic health in spontaneously conceived pregnancies. METHODS Participants in the North Carolina Early Pregnancy Study collected daily first-morning urine specimens while attempting to conceive. Samples were assayed for estrogen and progesterone metabolites (to identify day of ovulation) and hCG (to detect conception). Data were available for 190 pregnancies, 48 of which ended in early loss (within 6 weeks of the last menstrual period). We used logistic regression to identify characteristics associated with late implantation (≥10 days post-ovulation). For pregnancies surviving at least 6 weeks (n= 142), we used linear mixed models to identify factors associated with variations in hCG rise in the first 7 days from detection. RESULTS Later implantation was associated with current maternal smoking [odds ratio (OR): 5.7; 95% confidence interval (CI): 1.1-30] and with oocytes that were likely to have been fertilized late in their post-ovulatory lifespan (OR: 5.1; CI: 1.9-16). Older women had a faster rise in hCG (P= 0.01), as did women who had relatively late menarche (P for trend = 0.02). Women exposed in utero to diethylstilbestrol showed an unusual pattern of slow initial hCG rise followed by a fast increase, a pattern significantly different from that of unexposed women (P= 0.002). CONCLUSIONS Although limited by small numbers and infrequent exposures, our analyses suggest that a woman's exposures both early in life and at the time of pregnancy may influence early development of the conceptus.