Effect of macroscopic or microscopic blood and mucus on the success rates of embryo transfers

Reduced pregnancy and live birth rates after in vitro fertilization in women with cesarean section scar diverticulum: A retrospective cohort study

AIM

The primary aim of the study was to investigate the effect of cesarean scar diverticulum on the reproductive outcome of embryo transfer. The secondary aim was to assess the impact of endometrial cavity fluid on the reproductive outcome of embryo transfer among patients with a cesarean scar diverticulum.

METHODS

This was a retrospective cohort study. The study included 1538 patients, of whom 215 patients with an existing cesarean scar diverticulum and 1323 patients without cesarean scar diverticulum. A subgroup analysis of the impact of endometrial cavity fluid on the reproductive outcome of frozen embryo transfers among patients with a cesarean scar diverticulum was also conducted.

RESULTS

The odds of clinical pregnancy in the noncesarean section diverticulum group was higher than that in the diverticulum group (odds ratio [OR]: 1.72, 95% confidence interval [CI]: 1.27-2.34 and adjusted OR: 1.71, 95% CI: 1.25-2.34). The odds of live birth in the noncesarean section diverticulum group was also significantly higher than that in the cesarean section diverticulum group (OR: 1.61, 95% CI: 1.15-2.24 and adjusted OR: 1.59, 95% CI: 1.14-2.23). The existence of endometrial cavity fluid during endometrial preparation significantly reduced the pregnancy and live birth rate of frozen embryo transfer among the patients with cesarean section diverticulum.

CONCLUSION

The presence of cesarean section scar diverticulum had an adverse impact on the pregnancy and live birth rate after in vitro fertilization. The endometrial cavity fluid among the patients with cesarean section scar diverticulum accounted for the reduced pregnancy and live birth rate partly.

Reduced pregnancy and live birth rates after in vitro fertilization in women with previous Caesarean section: a retrospective cohort study

STUDY QUESTION

Does a previous Caesarean section affect reproductive outcomes, including live birth, in women after IVF or ICSI?

SUMMARY ANSWER

A previous Caesarean section impairs live birth rates after IVF or ICSI compared to a previous vaginal delivery.

WHAT IS KNOWN ALREADY

Rates of Caesarean sections are rising worldwide. Late sequelae of a Caesarean section related to a niche (Caesarean scar defect) include gynaecological symptoms and obstetric complications. A systematic review reported a lower pregnancy rate after a previous Caesarean section (RR 0.91 CI 0.87-0.95) compared to a previous vaginal delivery. So far, studies have been unable to causally differentiate between problems with fertilisation, and the transportation or implantation of an embryo. Studying an IVF population allows us to identify the effect of a previous Caesarean section on the implantation of embryos in relation to a previous vaginal delivery.

STUDY DESIGN, SIZE, DURATION

We retrospectively studied the live birth rate in women who had an IVF or ICSI treatment at the IVF Centre, Amsterdam UMC, location VUmc, Amsterdam, the Netherlands, between 2006 and 2016 with one previous delivery. In total, 1317 women were included, of whom 334 had a previous caesarean section and 983 had previously delivered vaginally.

PARTICIPANTS/MATERIALS, SETTING, METHODS

All secondary infertile women, with only one previous delivery either by caesarean section or vaginal delivery, were included. If applicable, only the first fresh embryo transfer was included in the analyses. Patients who did not intend to undergo embryo transfer were excluded. The primary outcome was live birth. Multivariate logistic regression analyses were used with adjustment for possible confounders ((i) age; (ii) pre-pregnancy BMI; (iii) pre-pregnancy smoking; (iv) previous fertility treatment; (v) indication for current fertility treatment: (a) tubal, (b) male factor and (c) endometriosis; (vi) embryo quality; and (vii) endometrial thickness), if applicable. Analysis was by intention to treat (ITT).

MAIN RESULTS AND THE ROLE OF CHANCE

Baseline characteristics of both groups were comparable. Live birth rates were significantly lower in women with a previous caesarean section than in women with a previous vaginal delivery, 15.9% (51/320) versus 23.3% (219/941) (OR 0.63 95% CI 0.45-0.87) in the ITT analyses. The rates were also lower for ongoing pregnancy (20.1 versus 28.1% (OR 0.64 95% CI 0.48-0.87)), clinical pregnancy (25.7 versus 33.8% (OR 0.68 95% CI 0.52-0.90)) and biochemical test (36.2 versus 45.5% (OR 0.68 95% CI 0.53-0.88)). The per protocol analyses showed the same differences (live birth rate OR 0.66 95% CI 0.47-0.93 and clinical pregnancy rate OR 0.72 95% CI 0.54-0.96).

LIMITATIONS, REASONS FOR CAUTION

This study is limited by its retrospective design. Furthermore, 56 (16.3%) cases lacked data regarding delivery outcomes, but these were equally distributed between the two groups.

WIDER IMPLICATIONS OF THE FINDINGS

The lower clinical pregnancy rates per embryo transfer indicate that implantation is hampered after a caesarean section. Its relation with a possible niche (caesarean scar defect) in the uterine caesarean scar needs further study. Our results should be discussed with clinicians and patients who consider an elective caesarean section.

STUDY FUNDING/COMPETING INTEREST(S)

Not applicable.

TRIAL REGISTRATION NUMBER

This study has been registered in the Dutch Trial Register (Ref. No. NL7631 http://www.trialregister.nl).

Effect of air bubbles localization and migration after embryo transfer on assisted reproductive technology outcome

OBJECTIVE

To evaluate the effect of embryo flash position and movement of the air bubbles at 1 and 60 minutes after ET on clinical pregnancy rates (PRs).

DESIGN

Prospective clinical trial.

SETTING

University fertility clinic.

PATIENT(S)

A total of 230 fresh ultrasound-guided ETs performed by a single physician (C.F.) at the IVF center of Yeditepe University Hospital between September 2016 and February 2017 were included.

INTERVENTION(S)

Transabdominal ultrasonographic guidance at ET.

MAIN OUTCOME MEASURE(S)

Clinical PRs.

RESULT(S)

There was no significant difference in terms of clinical PRs between women with embryo flash located >15 mm and <15 mm from the fundus at 1 or 60 minutes (P=.6 and P=.7, respectively). The PRs in women with embryo flash located <15 mm and >15 mm from the fundus were 47% and 60%, respectively (P=.6). The clinical intrauterine PRs were 69.5%, 38.5%, and 19.1% in fundal, static, and cervical, respectively. The highest PR was in fundal when compared with others (P<.01). The clinical PR appears to be associated with the embryo flash movement/migration and the PR was dramatically reduced when the embryo migrated from its original position toward the cervix at 60 minutes.

CONCLUSION(S)

We concluded that clinical PR appears to be associated with the embryo flash movement/migration at 60 minutes after ET and embryo flash movement toward the fundus is associated with higher clinical PRs. Further well-designed randomized controlled trials are required to optimize ET technique in the future.

Does the Presence of Blood in the Catheter or the Degree of Difficulty of Embryo Transfer Affect Live Birth?

The technique used for embryo transfer (ET) can affect implantation. Prior research that evaluated the effect of postprocedural blood of the transfer catheter tip have yielded mixed results, and it is unclear whether this is actually a marker of difficulty of the transfer. Our objective was to estimate the effect of blood at the time of ET and the difficulty of ET on live birth rates (LBR). This retrospective cohort study utilized generalized estimating equations (GEEs) with nesting for repeated cycles for all analyses. Univariate modeling was performed and a final multivariate (adjusted) GEE model accounted for all significant confounders. Embryo transfers were subjectively graded (easy, medium, or hard) by a physician at the time of transfer. The presence of blood at ET was associated with more difficult ETs, retained embryos, and presence of mucous in the catheter. In the univariate analysis, ET with blood was not associated with live birth, while the degree of difficulty for ET had a negative impact on LBR. In the final multivariate GEE model, which accounts for repeated cycles from a patient, the only factors associated with an increased LBR were the degree of difficulty of the ET, female age, and blastocyst transfer. After controlling for confounding variables, the presence of blood in the transfer catheter was not associated with the likelihood of pregnancy and thus was not an independent predictor of cycle outcome. This indicates that the difficulty of the transfer itself was a strong negative predictor of pregnancy.

Impact of a prior cesarean delivery on embryo transfer: a prospective study

OBJECTIVE

To determine whether a history of prior cesarean delivery (CD) makes ET more difficult and impacts pregnancy outcomes.

DESIGN

Prospective cohort study.

SETTING

Tertiary care military facility.

PATIENT(S)

One hundred ninety-four patients with previous delivery undergoing IVF/intracytoplasmic sperm injection (ICSI)-ET.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Live birth (primary), positive hCG, clinical pregnancy, and time to perform ET.

RESULT(S)

There was no statistically significant difference between patients with a history of only vaginal deliveries versus those with a history of CD for live birth (39% vs. 32%), positive hCG (56% vs. 53%), or clinical pregnancy (49% vs. 41%). Embryo transfers took longer in the history of CD group (157 vs. 187 seconds) and were more likely to have mucus (27% vs. 45%) or blood (8% vs. 21%) on the catheter.

CONCLUSION(S)

Embryo transfers performed on patients with a prior CD took 30 seconds longer. They were also more likely to have blood or mucus on the catheter. Despite the apparently more difficult transfers, pregnancy outcomes were not different between the two groups.