The PLART study: incidence of preterm labor and adverse pregnancy outcomes after assisted reproductive techniques-a retrospective cohort study

Placenta Accreta Spectrum Disorder Complicated with Endometriosis: Systematic Review and Meta-Analysis

This study aimed to assess the relationship between placenta accreta spectrum disorder (PASD) and endometriosis. The relationships among pregnancy, assisted reproductive technology (ART), placenta previa, ART-conceived pregnancy and PASD were also determined. A systematic literature review was conducted using multiple computerized databases. Forty-eight studies (1990–2021) met the inclusion criteria. According to the adjusted pooled analysis (n = 3), endometriosis was associated with an increased prevalence of PASD (adjusted odds ratio [OR] 3.39, 95% confidence interval [CI] 1.96–5.87). In the included studies, the ART rate ranged from 18.2% to 37.2% for women with endometriosis. According to the adjusted pooled analysis, women who used ART were more likely to have placenta previa (n = 13: adjusted OR 2.96, 95%CI, 2.43–3.60) and PASD (n = 4: adjusted OR 3.54, 95%CI 1.86–6.76) than those who did not use ART. According to the sensitivity analysis using an unadjusted analysis accounting for the type of ART, frozen embryo transfer (ET) was associated with an increased risk of PASD (n = 4: OR 2.79, 95%CI, 1.22−6.37) compared to fresh ET. Endometriosis may be associated with an increased rate of PASD. Women with placenta previa complicated with endometriosis who conceived using frozen ET may be a high risk for PASD.

Association of Preterm Singleton Birth With Fertility Treatment in the US

IMPORTANCE

Preterm birth is a global health issue. The association between fertility treatment and preterm singleton births has not been clarified.

OBJECTIVE

To examine the association between fertility treatment and preterm birth.

DESIGN, SETTING, AND PARTICIPANTS

This population-based cohort study used birth data that were submitted by 50 states and the District of Columbia to the National Vital Statistics System database. All mothers in the database who had a singleton live birth from January 1, 2016, to December 31, 2019, were included. Those who had preexisting hypertension or diabetes were excluded.

EXPOSURES

Fertility treatment categorized as assisted reproductive technology (ART) or non-ART treatment.

MAIN OUTCOMES AND MEASURES

The main outcome was a diagnosis of preterm birth, which was defined as birth before 37 complete weeks (<259 days) of gestation. Gestational age was calculated by obstetric estimation at delivery and was collected from the database.

RESULTS

The final sample consisted of 14 370 920 mothers (mean [SD] age, 28.79 [5.79] years) with singleton live births. Of these women, 122 944 (0.9%) conceived by ART and 71 176 (0.5%) received non-ART treatment. The prevalence of preterm birth was 7.6% (n = 1 071 994) in natural conception, 10.7% (n = 13 205) in ART, and 9.3% (n = 6629) in non-ART groups. Compared with neonates who were naturally conceived, newborns who were conceived with ART (adjusted risk difference [aRD], 3.10% [95% CI, 2.93%-3.27%]; adjusted odds ratio [aOR], 1.49 [95% CI, 1.46-1.52]; P < .001) and non-ART treatment (aRD, 2.22% [95% CI, 2.00%-2.44%]; aOR, 1.35 [95% CI, 1.31-1.38]; P < .001) had significantly higher risk for preterm birth after full adjustment. These associations were similar in subgroups of participants as defined by baseline characteristics.

CONCLUSIONS AND RELEVANCE

This study found that singleton neonates who were conceived by fertility treatment had higher rates of preterm birth. Further investigations are warranted into the association between ART or non-ART treatment and the risk of preterm birth in singleton neonates.

The vitrification system may affect preterm and cesarean delivery rates after single vitrified blastocyst transfer

The purpose of this study was to investigate the possible effects of different vitrification systems on single vitrified blastocyst transfer cycles. The clinical and birth outcomes of 412 patients who underwent single vitrified blastocyst transfer between January 2018 and June 2020 were retrospectively analyzed and compared between patients who underwent blastocyst vitrification with kit A (group A, 196 patients) and those who underwent blastocyst vitrification with kit B (group B, 216 patients). Clinical outcomes, including the clinical pregnancy rate, ongoing pregnancy rate, early miscarriage rate, late miscarriage rate, ectopic pregnancy rate, twin pregnancy rate, and induced labor rate due to fetal malformation, were not significantly different between the two groups (P > 0.05). The preterm delivery rate among singleton newborns (11.57% vs. 3.23%, P < 0.05) and the cesarean delivery rate were significantly higher in group B than in group A (70.25% vs. 57.26%, P < 0.05). Birth outcomes, including the male-to-female ratio, low-birth-weight rate, macrosomia rate, birth defect rate, newborn gestational age, neonatal body weight, and singleton neonatal body length, were not significantly different (P > 0.05). Our findings suggest that different vitrification systems might differentially affect birth outcomes. Such disparity could reflect differences in kit composition and/or protocol.ABBREVIATIONS: DMSO: dimethyl sulfoxide; ES: equilibration solution; VS: vitrification solution; BMI: body mass index; ICSI: intracytoplasmic sperm injection; OR: odds ratio; CI: confidence interval.

The effect of endometrial thickness on live birth outcomes in women undergoing hormone-replaced frozen embryo transfer

Objective

To determine the impact of endometrial thickness on live birth outcomes and obstetric complication rate after hormone-replaced frozen embryo transfer.

Design

Retrospective cohort study.

Setting

Large, urban, academic fertility center.

Patients

All patients with a singleton live birth after single euploid embryo transfer (by array comparative genomic hybridization or next-generation sequencing) in a hormone-replaced frozen embryo transfer cycle between January 2017 and December 2018 were reviewed.

Interventions

None.

Main Outcome measures

The primary outcomes were birth weight and obstetric complication rate.

Results

A total of 492 patients were included. The median endometrial thickness was 8.60 mm (range, 6.0-20.0). The median gestational age at live birth was 39.4 weeks with a median birth weight of 3,345.2 g. Endometrial thickness was significantly correlated with birth weight. When patients were dichotomized into groups (those with an endometrial thickness of <7 mm and those with an endometrial thickness of >7 mm), neonates born from endometria with a thickness of <7 mm were born earlier (37.3 vs. 39.4 weeks and born with lower birth weights (2,749.9 vs. 3,345.2 g). It should be noted that only seven patients had an endometrium measuring <7 mm. Moreover, 7.1% (n = 35) of patients had an obstetric complication. Endometrial thickness was not significantly associated with obstetric complications, even with adjustments for age and medical history.

Conclusions

Endometrial thickness may be a valuable predictor of placental health and birth weight. Further study is required to examine the relationship with individual obstetric complications, as our study may not have been powered to observe differences in obstetric complication rate, as well as the relationship between endometrial thickness and outcomes in natural frozen embryo transfer cycles.

Prevention of preterm birth: Proactive and reactive clinical practice-are we on the right track?

Preterm birth remains the major cause of death and disability among children under the age of five. In developing countries antenatal preterm birth prevention clinics are set up to provide cervical length surveillance and/or treatment modalities such as cerclage or progesterone for those women with identified risk factors such as previous cervical treatment or preterm birth. However, 85% of women have no risk factors for PTB and currently there is no biomarker to screen women early in pregnancy. Women will present unexpectedly in threatened preterm labour and we have no choice but to adopt a re-active approach to their care by using predication and preparation strategies such as fetal fibronectin, tocolytic therapy and steroids. Despite these strategies approximately 15-20% of these women will give birth preterm before 34 weeks. There is a urgent need to re-design primary, secondary and tertiary prevention strategies for spontaneous preterm labour (sPTL) in singleton pregnancies aimed at identifying and addressing key gaps in clinical practice and research.

Pregnancy outcomes in women with history of surgery for endometriosis

OBJECTIVE

To assess the relationship between history of surgery for endometriosis and adverse obstetrical outcomes.

DESIGN

Retrospective study using prospectively recorded data.

SETTING

Referral center.

PATIENT(S)

Total of 569 women with history of surgery for endometriosis, postoperative conception, and pregnancy evolution over 22 weeks of gestation.

INTERVENTIONS(S)

Surgery for endometriosis.

MAIN OUTCOME MEASURE(S)

Small for gestational age (SGA) status of the newborn, spontaneous preterm birth (PT, before 37 weeks' gestation), and placenta previa.

RESULTS

Among 733 pregnancies included in the study, 566 deliveries were recorded (77.2%), of which 535 were singleton (72.9% of pregnancies) and 31 twins (4.2%). SGA was observed in 81 of 535 (15.1%) singleton pregnancies and in 9 of 31 (29%) twin pregnancies. PT occurred in 53 of 535 (9.9%) singleton pregnancies and in 19 of 31 (61.2%) twin pregnancies. The number of singleton and multiple pregnancies complicated by placenta previa were, respectively, 9 of 535 (1.7%) and 0 of 31. The independent factor found to relate to SGA was the absence of endometriomas; conception with the use of assisted reproductive technologies (ART) only tended toward statistical significance. Independent factors found to increase risk of PT were conception with the use of ART, body mass index >30 kg/m², and surgery of deep endometriosis infiltrating the rectum and the bladder. Independent factors associated with placenta previa were conception with the use of ART and history of stage III or IV endometriosis.

CONCLUSION(S)

The risk of SGA and PT is increased in women with a history of surgery for endometriosis, and a high rate of conception with the use of ART may jeopardize outcomes.

Preterm Birth in Assisted Reproductive Technology: An Analysis of More Than 20,000 Singleton Newborns

BACKGROUND

Several studies have shown that newborns conceived through the ART procedures were associated with an increased incidence of preterm delivery compared to those conceived spontaneously regardless of the type of ART procedure. The aim of the study was to explore risk factors for preterm birth (PTB) in assisted reproductive technology.

METHOD

In this single center retrospective cohort study, a total of 23,111 singleton newborns from January 2010 to December 2018 were included. The primary outcome in this study was preterm birth, defined as live birth before 37 weeks' gestation.

RESULT

In the 23,111 pregnancies, the incidence of PTB was 7.13%. In multivariate logistic regression analysis model, BMI was an independent predictor for PTB (OR = 1.05, 95% CI: 1.03-1.07; P = 0.00 in IVF/ICSI cycles; OR = 1.08, 95% CI: 1.03-1.12; P = 0.00 in IUI cycles). Also, another independent predictor in ART was male newborns (OR = 1.27, 95% CI: 1.14-1.41; P = 0.00 in IVF/ICSI cycles; OR = 1.60, 95% CI: 1.17-2.18; P = 0.00 in IUI cycles). In IVF/ICSI cycles, PTB was significantly higher in patients with advanced age (9.56% in ≥ 38 years old), and in patients with a history of cesarean section (10.39%). In addition, Blastocyst transfer, and frozen thawed transfer were also risk factor for PTB as compared with cleavage transfer, and fresh transfer, respectively. Moreover, in frozen thawed transfer cycles, stimulated protocol (estrogen-progesterone) increased PTB as compared with natural protocol (OR = 1.33, 95% CI: 1.12-1.59; P = 0.00). This situation was similar in IUI cycles as stimulated protocol also increased PTB when compared with natural protocol (OR = 1.72, 95% CI: 1.19-2.48; P = 0.00).

CONCLUSION

Body mass index (BMI), delivery with male newborn, as well as stimulated protocols, were independent risk factors for PTB in both IVF/ICSI and IUI treatment cycles. In IVF/ICSI cycles, independent risk factors also included maternal, history of cesarean section, frozen thawed transfer, and blastocyst transfer.