Randomized trial of screening for preterm birth in low-risk women - the preterm birth screening study.

BACKGROUND: Preterm birth is a major cause of perinatal morbidity and mortality. It is unclear whether the introduction of a universal transvaginal ultrasound cervical length screening program in women at low risk for preterm delivery is associated with a reduction in the frequency of preterm birth. OBJECTIVE: To test the hypothesis that the introduction of a midtrimester universal transvaginal ultrasound cervical length screening program in asymptomatic singleton pregnancies without prior preterm delivery would reduce the rate of preterm birth at <37 weeks of gestation. STUDY DESIGN: This study was a multicenter nonblinded randomized trial of screening of asymptomatic singleton pregnancies without prior spontaneous preterm birth, who were randomized to either cervical length screening program (ie, intervention group) or no screening (ie, control group). Participants were randomized at the time of their routine anatomy scan between 18 0/7 and 23 6/7 weeks of gestation. Women randomized in the screening group received cervical length measurement. Those who were found to have cervical length ≤25 mm were offered 200 mg vaginal progesterone daily along with cervical pessary. The primary outcome was preterm birth at <37 weeks. The risk of primary outcome was quantified by the relative risk with 95% confidence interval, and was based on the intention-to-screen principle. RESULTS: A total of 1334 asymptomatic women with singleton pregnancies and without prior preterm birth, were included in the trial. Out of the 675 women randomized in the transvaginal ultrasound cervical length screening group, 13 (1.9%) were found to have transvaginal ultrasound cervical length ≤25 mm during the screening. Preterm birth at <37 weeks of gestation occurred in 48 women in the transvaginal ultrasound cervical length screening group (7.5%), and 54 women in the control group (8.7%) (relative risk, 0.86; 95% confidence interval, 0.59-1.25). Women randomized in the transvaginal ultrasound cervical length screening group had no significant differences in the incidence of preterm birth at less than 34, 32, 30, 28, and 24 weeks of gestation. CONCLUSION: The introduction of a universal transvaginal ultrasound cervical length screening program at 18 0/6 to 23 6/7 weeks of gestation in singleton pregnancies without prior spontaneous preterm birth, with treatment for those with cervical length ≤25 mm, did not result in significant lower incidence of preterm delivery than the incidence without the screening program.

Outpatient Use of Monoclonal Antibodies Casirivimab and Imdevimab in Pregnancy for Mild-to-Moderate Coronavirus Disease 2019.

OBJECTIVE: The aim of this study was to report the use casirivimab/imdevimab therapy in pregnant women with moderate coronavirus disease 2019 (COVID-19). STUDY DESIGN: We report 12 cases of unvaccinated pregnant patients with mild-to-moderate COVID-19 treated with casirivimab/imdevimab. RESULTS: Twelve unvaccinated pregnant patients with mild-to-moderate COVID-19 received casirivimab/imdevimab at the dose of 1200/1200 mg by intravenous infusion over 60 minutes. All women were managed outpatient. None experienced severe adverse drug reaction and none progressed to severe disease. CONCLUSION: Casirivimab/imdevimab should be considered for outpatient treatment of unvaccinated pregnant women with mild-to-moderate COVID-19 to decrease the risk of severe disease. KEY POINTS: · Casirivimab/imdevimab is not well studied in pregnant women.. · Casirivimab/imdevimab in pregnant women with mild-to-moderate COVID-19 decreases the risk of severe disease.. · Casirivimab/imdevimab in pregnant women with mild-to-moderate COVID-19 is well tolerated..

PROMPT: Prospective Meta-analysis for Pessary Trials Study Protocol.

OBJECTIVE: Preterm birth, defined as birth before 37 weeks of gestation, is a leading cause of perinatal and infant mortality throughout the world. Preterm birth is also associated with long-term neurological disabilities and other significant health issues in children. A short cervix in the second trimester has been noted to be one of the strongest predictors of subsequent spontaneous preterm birth in both singleton and multiple pregnancies. Some studies have shown that cervical support in the form of an Arabin pessary lowers the risk of preterm birth in women with a singleton gestation and short cervical length; however, other studies have conflicting results. Our objective was to form an international collaborative of planned or ongoing randomized trials of pessary in singleton and twin gestations with a short cervix. STUDY DESIGN: In November 2014, an international group of investigators, who had initiated or were planning randomized trials of pessary for pregnant people with a short cervix and singleton or twin gestation to prevent preterm birth, formed a collaboration to plan a prospective individual patient data (IPD) meta-analysis of randomized trials (PROspective Meta-analysis of Pessary Trials [PROMPT]). The PROMPT investigators agreed on meta-analysis IPD hypotheses for singletons and twins, eligibility criteria, and a set of core baseline and outcome measures. The primary outcome is a composite of fetal death or preterm delivery before 32 weeks' gestation. Secondary outcomes include maternal and neonatal morbidities. The PROMPT protocol may be viewed as a written agreement among the study investigators who make up the PROMPT consortium (PROSPERO ID# CRD42018067740). RESULTS: Results will be published in phases as the individual participating studies are concluded and published. Results of the first phase of singleton and twin pessary trials are expected to be available in late 2022. Updates are planned as participating trials are completed and published. KEY POINTS: · Short cervical length predicts preterm birth.. · Results of prior cervical pessary trials are mixed.. · Meta-analysis of pessary trials protocol..

Effects of depth of neuromuscular block on surgical operating conditions in women undergoing gynecologic laparoscopic surgery: a randomized clinical trial.

BACKGROUND: In recent years, the relationship between the advantages and disadvantages of a deep neuromuscular block (DNMB), compared to a moderate block (MNMB) in laparoscopic surgery, has been increasingly studied. OBJECTIVE: Evaluate the effect of D-NMB compared to M-NMB in gynecological laparoscopic surgery. METHODS: This was a parallel-group, double-blind, randomized clinical trial, conducted at a single center in Italy between February 2020 and July 2020. American Society of Anesthesiologist (ASA) I-II risk class patients scheduled for elective gynecological laparoscopic surgery were randomized into a 1:1 ratio to either experimental or control group. The first one included DNMB with a rocuronium bolus at the starting dose of 1.2 mg/kg and a maintenance dose (0.3-0.6 mg/kg/h). The second one included MNMB with a rocuronium bolus at the starting dose of 0.6 mg/kg, and a maintenance dose in boluses (0.15-0.25 mg/kg). The primary outcome was the intraoperative surgical condition assessed every 15 min by the surgeon as a 5-point scale. The secondary outcome was the time needed to discharge patients from post-anesthesia care unit (PACU). The tertiary outcome was the assessment of the intra-operative hemodynamic instability. A sample size of 50 patients was planned. RESULTS: One hundred five patients were assessed for eligibility, 55 were excluded. Fifty patients met the inclusion criteria and were enrolled. The average score for the operative field was 4 for the D-NMB group and 3 for the M-NMB group (p value < 0.01). The length of stay in PACU was 13 min for the DNMB group and 22 min for the MNMB group (p value = 0.02). CONCLUSIONS: Deep neuromuscular block improves intraoperative surgical condition during gynecological laparoscopic surgery. TRIAL REGISTRATION: clinicalTrials.gov NCT03441828.

Hysteroscopic resection vs ultrasound-guided dilation and evacuation for treatment of cesarean scar ectopic pregnancy: a randomized clinical trial.

BACKGROUND: Cesarean scar ectopic pregnancy is a type of ectopic pregnancy in which the fertilized egg is implanted in the muscle or fibrous tissue of the scar after a previous cesarean delivery. The condition can be catastrophic if not managed on time and can lead to significant morbidity and mortality. Several approaches have been studied for the management of cesarean scar ectopic pregnancy in women who opted for termination of pregnancy with no consensus on the best treatment modality reached so far. OBJECTIVE: This study aimed to compare the success rate of hysteroscopic resection vs ultrasound-guided dilation and evacuation for the treatment of cesarean scar ectopic pregnancy. STUDY DESIGN: This was a parallel group, nonblinded, randomized clinical trial conducted at a single center in Italy. Women with singleton gestations at <8 weeks and 6 days of gestation were included in the study. Inclusion criteria were women with a cesarean scar ectopic pregnancy with positive embryonic heart activity who opted for termination of pregnancy. Patients were randomized 1:1 to receive either hysteroscopic resection (ie, intervention group) or ultrasound-guided dilation and evacuation (ie, control group). Both groups received 50 mg/m2 of methotrexate intramuscularly at the time of randomization (day 1) and another dose at day 3. A third dose of methotrexate was planned in case of persistence of positive fetal heart activity at day 5. Participants received either ultrasound-guided dilation and evacuation or hysteroscopic resection from 1 to 5 days after the last dose of methotrexate. Hysteroscopic resection was performed under spinal anesthesia using a 15 Fr bipolar mini-resectoscope. Dilation and evacuation were performed by vacuum aspiration with a Karman cannula, followed by sharp curettage, if necessary, under ultrasound guidance. The primary outcome was the success rate of the treatment protocol, defined as no further treatment required until the complete resolution of the cesarean scar ectopic pregnancy. Resolution of the cesarean scar ectopic pregnancy was evaluated based on decline of beta-hCG and the absence of residual gestational material in the endometrial cavity. Treatment failure was defined as the necessity for further treatment required until the complete resolution of the cesarean scar ectopic pregnancy. A sample size calculation indicated that 54 participants were required to test the hypothesis RESULTS: A total of 54 women were enrolled and randomized. Number of previous cesarean deliveries ranged from 1 to 3. Overall, 10 women received a third dose of methotrexate with 7 of 27 (25.9%) participants in the hysteroscopic resection group and 3 of 27 (11.1%) in the dilation and evacuation group. The success rate was 100% (27/27) in the hysteroscopic resection group and 81.5% (22/27) in the dilation and evacuation group (relative risk, 1.22; 95% confidence interval, 1.01-1.48). Additional procedures were required in 5 cases of the control group, namely 3 hysterectomies, 1 laparotomic uterine segmental resection, and 1 hysteroscopic resection. The length of stay in the hospital was 9.0±2.9 days in the intervention group and 10.0±3.5 days in the control group (mean difference, -1.00 days; 95% confidence interval, -2.71 to 0.71). No cases of admission to intensive care unit or maternal death were reported. CONCLUSION: Hysteroscopic resection was associated with an increased success rate in the treatment of cesarean scar ectopic pregnancy when compared with ultrasound-guided dilation and evacuation.

Perinatal depression during the fourth wave of the COVID-19 outbreak in a single prenatal clinic in Southern Italy: The role of loneliness, anxiety, and maternal support.

Background: The current study aimed at assessing the levels of perinatal depression (i.e., both antenatal and postnatal) during the fourth wave of the COVID-19 outbreak in a group of Italian women, as well as to evaluate the role of loneliness, anxiety, and lack of maternal support in cumulatively predicting perinatal depression. Methods: A cross-sectional study was conducted with 200 Italian women recruited during a peak of the COVID-19 pandemic in Italy (i.e., from September to December 2021) from a single prenatal clinic in Southern Italy. A non-parametric binomial test was conducted to assess whether the perinatal depression frequencies of the current sample differed from those found in a pre-Covid reference group. Additionally, hierarchical multiple linear regression analyses assessing whether loneliness, anxiety, and maternal support affected women's perinatal depression were also conducted. Results: The general prevalence of perinatal depression was significantly higher in participants recruited during the fourth wave of the COVID-19 pandemic compared to the pre-Covid reference group (29% vs. 9.2%). However, results showed that, contrary to postnatal depression (18.2% vs. 19.9%), only the prevalence of antenatal depression was significantly higher compared to the pre-Covid reference group (39.6% vs. 6.4%). Furthermore, loneliness and anxiety, but not maternal support, were associated with higher levels of PD. Limitations: Limitations concerned the cross-sectional nature of the study and the relatively small sample size. Conclusions: This study sheds light on the need to address perinatal mental health of women during major stressful events, such as the COVID-19 pandemic.

Clinical Experience with Genome-Wide Noninvasive Prenatal Screening in a Large Cohort of Twin Pregnancies.

Non-invasive prenatal screening (NIPS) in twin gestations has been shown to have high detection rates and low false-positive rates for trisomy 21, as seen in singleton pregnancies, although there have been few large cohort twin studies, genome-wide studies in particular, to date. In this study, we looked at the performance of genome-wide NIPT in a large cohort consisting of 1244 twin pregnancy samples collected over a two-year period in a single laboratory in Italy. All samples underwent an NIPS for common trisomies, with 61.5% of study participants choosing to undergo genome-wide NIPS for additional fetal anomalies (namely, rare autosomal aneuploidies and CNVs). There were nine initial no-call results, all of which were resolved upon retest. Based on our NIPS results, 17 samples were at high risk for trisomy 21, one for trisomy 18, six for a rare autosomal aneuploidy, and four for a CNV. Clinical follow-up was available for 27 out of 29 high-risk cases; a sensitivity of 100%, a specificity of 99.9%, and a PPV of 94.4% were noted for trisomy 21. Clinical follow-up was also available for 1110 (96.6%) of the low-risk cases, all of which were true negatives. In conclusion, we found that NIPS was a reliable screening approach for trisomy 21 in twin pregnancies.

Activity restriction for women with arrested preterm labor: a randomized controlled trial.

BACKGROUND: In the past, some pregnant women have been recommended to be in activity restriction because of the presumed increased risk of preterm birth due to the increased release of catecholamines, which might stimulate myometrial activity, during exercise and aerobic activity. OBJECTIVE: This study aimed to test the hypothesis that in women with singleton pregnancy and arrested preterm labor, activity restriction would reduce the rate of preterm birth at <37 weeks of gestation. STUDY DESIGN: This was a parallel-group nonblinded randomized trial conducted at a single center in Italy. Eligible patients were those with a diagnosis of arrested preterm labor, defined as not delivering after 48 hours of hospitalization for threatened preterm labor, with transvaginal ultrasound cervical length ≤25 mm, no other symptoms of possible uterine contractions, and cervical dilatation <3 cm at pelvic examination. Inclusion criteria were singleton pregnancies between 24 0/7 and 33 6/7 weeks of gestation. Participants were randomized in a 1:1 ratio to either activity restriction at the time of discharge or no activity restriction. Women in the intervention group were recommended activity restriction, defined as the following: pelvic rest, prohibition of sexual activity, and reduction of work and/or nonwork activity. The primary endpoint was preterm birth at <37 weeks of gestation. RESULTS: A total of 120 participants were included in the trial; 60 patients were enrolled in the activity restriction group and 60 in the control group. Preterm birth at <37 weeks of gestation occurred in 15 of 60 women (25.0%) in the activity restriction group and 23 of 60 women (38.3%) in the control group (relative risk, 0.65; 95% confidence interval, 0.38-1.12). There was no significant between-group difference in the incidence of preterm birth at <32 weeks and in neonatal outcomes, but the trial was not powered for these outcomes. CONCLUSION: In singleton gestations with arrested preterm labor, activity restriction, including pelvic rest, prohibition of sexual activity, and reduction of work and/or nonwork activity, does not result in a lower rate of preterm birth at <37 weeks. Given the evidence on the lack of benefits, use of activity restriction in this population should be discouraged.

The impact of COVID-19 pandemic on obstetrics and gynecology hospitalization rate and on reasons for seeking emergency care: a systematic review and meta-analysis.

BACKGROUND: During the lockdown due to COVID-19 pandemic, utilization of emergency care units has been reported to be reduced for obstetrical and gynaecological reasons. The aim of this systematic review is to assess if this phenomenon reduced the rate of hospitalizations for any reason and to evaluate the main reasons for seeking care in this subset of the population. METHODS: The search was conducted using the main electronic databases from January 2020 to May 2021. The studies were identified with the use of a combination of: "emergency department" OR "A&E" OR "emergency service" OR "emergency unit" OR "maternity service" AND "COVID-19" OR "COVID-19 pandemic" OR "SARS-COV-2" and "admission" OR "hospitalization". All the studies that evaluated women going to obstetrics & gynecology emergency department (ED) during the COVID-19 pandemic for any reason were included. RESULTS: The pooled proportion (PP) of hospitalizations increased from 22.7 to 30.6% during the lockdown periods, in particular from 48.0 to 53.9% for delivery. The PP of pregnant women suffering from hypertensive disorders increased (2.6 vs 1.2%), as well as women having contractions (52 vs 43%) and rupture of membranes (12.0 vs 9.1%). Oppositely, the PP of women having pelvic pain (12.4 vs 14.4%), suspected ectopic pregnancy (1.8 vs 2.0), reduced fetal movements (3.0 vs 3.3%), vaginal bleeding both for obstetrical (11.7 vs 12.8%) and gynecological issues (7.4 vs 9.2%) slightly reduced. CONCLUSION: During the lockdown, an increase in the proportion of hospitalizations for obstetrical and gynecological reasons has been registered, especially for labor symptoms and hypertensive disorders.

Do Anti-SARS-CoV-2 Monoclonal Antibodies Have an Impact on Pregnancy Outcome? A Systematic Review and Meta-Analysis.

Monoclonal antibodies (mAbs) have been used as a rescue strategy for pregnant women affected by COVID-19. To explore its impact on maternal-fetal health, we included all observational studies reporting maternal, fetal, delivery and neonatal outcomes in women who underwent mAbs infusion for COVID-19. Primary outcome was the percentage of preterm delivery. We used meta-analyses of proportions to combine data for maternal, fetal, delivery and neonatal outcome of women treated with mAbs for COVID-19 and reported pooled proportions and their 95% confidence intervals (CIs) for categorical variables or mean difference (MD) with their 95% confidence intervals for continuous variables. Preterm birth was observed in 22.8% of cases (95% CI 12.9-34.3). Fetal distress was reported in 4.2% (95% CI 1.6-8.2). Gestational hypertension and pre-eclampsia were observed in 3.0% (95% CI 0.8-6.8) and 3.4% (95% CI 0.8-7.5) of cases, respectively. Fetal growth restriction was observed in 3.2% of fetuses (95% CI 0.8-7.0). Secondary prophylaxis with mAbs is currently considered the best treatment option for people with mild to moderate COVID-19 disease. More attention should be paid to infants born from mothers who were treated with mAbs, for the risk of immunosuppression.

Use of artificial intelligence in obstetrics: not quite ready for prime time.

Artificial intelligence is finding several applications in healthcare settings. This study aimed to report evidence on the effectiveness of artificial intelligence application in obstetrics. Through a narrative review of literature, we described artificial intelligence use in different obstetrical areas as follows: prenatal diagnosis, fetal heart monitoring, prediction and management of pregnancy-related complications (preeclampsia, preterm birth, gestational diabetes mellitus, and placenta accreta spectrum), and labor. Artificial intelligence seems to be a promising tool to help clinicians in daily clinical activity. The main advantages that emerged from this review are related to the reduction of inter- and intraoperator variability, time reduction of procedures, and improvement of overall diagnostic performance. However, nowadays, the diffusion of these systems in routine clinical practice raises several issues. Reported evidence is still very limited, and further studies are needed to confirm the clinical applicability of artificial intelligence. Moreover, better training of clinicians designed to use these systems should be ensured, and evidence-based guidelines regarding this topic should be produced to enhance the strengths of artificial systems and minimize their limits.

Characteristics of Placental Histopathology in Women with Uncomplicated Pregnancies Affected by SARS-CoV-2 Infection at the Time of Delivery: A Single-Center Experience.

The aim of this study was, firstly, to analyze the histopathological characteristics of placentas in women with uneventful pregnancies and affected by COVID-19 at the time of delivery; and secondly, to correlate histological findings to maternal and neonatal characteristics. In our single-center prospective observational study, 46 placentas from term uncomplicated singleton pregnancies of patients with a documented SARS-CoV-2 infection at the time of delivery underwent histological examination. Despite a normal feto-maternal outcome, most of the placentas (82.6%) presented signs of maternal vascular malperfusion, while features of fetal vascular malperfusion were found in 54% of cases. No correlation was detected between maternal and neonatal characteristics and the severity of blood circulation disease, and abnormal findings were also described in asymptomatic patients. Moreover, we did not find any maternal symptoms or clinical details allowing for the prediction of abnormal placental findings in pregnancy complicated by COVID-19 infection. Our results suggest that SARS-CoV-2 infection during pregnancy could lead to acute placental dysfunction.

Suture type for hysterotomy closure: a systematic review and meta-analysis of randomized controlled trials.

OBJECTIVE: Recent randomized controlled trials have demonstrated an association between uterine closure technique at the time of cesarean delivery and short- and long-term operative outcomes with varied results. This systematic review and meta-analysis aimed to examine types of suture material used for cesarean delivery. DATA SOURCES: Scopus, PubMed, Cochrane Central Register of Controlled Trials, Ovid, and ClinicalTrials.gov were searched from inception of each database to October 2021. STUDY ELIGIBILITY CRITERIA: All randomized controlled trials that compared types of suture materials used for hysterotomy closure during low-transverse cesarean delivery at ≥24 weeks' gestation and examined maternal outcomes were included for this review. The primary outcome was estimated blood loss. Secondary outcomes included additional surgical complications. METHODS: Results were summarized as mean difference or risk ratio with associated 95% confidence intervals. The quality of studies was evaluated with the Cochrane Handbook for Systematic Reviews of Interventions for judging risk of bias. Heterogeneity was measured using I-squared (Higgins I2). RESULTS: This review included 7 randomized controlled trials, of which 3 compared multifilament with barbed suture (136 vs 136 participants), 3 compared multifilament with conventional monofilament suture (245 vs 244 participants), and 1 trial compared multifilament with chromic suture (4590 vs 4595 participants). Primary analysis showed no difference in estimated blood loss between the multifilament and the barbed suture group (mean difference, 46.2 mL; 95% confidence interval, -13.6 to 105.9), nor in change in hemoglobin concentration between the multifilament and the conventional monofilament group (mean difference, -0.1%; 95% confidence interval, -0.5 to 0.3). Secondary outcomes showed a reduction in operative time with barbed vs multifilament suture (mean difference, 1.9 minutes; 95% confidence interval, 0.03-3.8). Analysis also demonstrated an increased uterine scar thickness with use of conventional monofilament vs multifilament suture (mean difference, -1.05 mm; 95% confidence interval, -1.9 to -0.2). CONCLUSION: This meta-analysis does not support a specific type of suture material for uterine closure at cesarean delivery because of insufficient data. Although barbed suture was associated with an overall decrease in operative time, and use of conventional monofilament suture was associated with an increase in uterine scar thickness, the clinical utility of these differences is not clear. Further adequate randomized controlled trials are warranted for evaluation of different suture materials for hysterotomy closure.

Outcomes among participants vs nonparticipants of randomized trials during pregnancy: a systematic review and meta-analysis.

OBJECTIVE: This study aimed to evaluate the outcomes among individuals who were eligible and approached for participation in a randomized controlled trial during pregnancy, comparing those who enrolled with those who declined participation. DATA SOURCES: MEDLINE, Scopus, CINAHL, the Cochrane Library, and Ovid were searched from study inception to May 2022. STUDY ELIGIBILITY CRITERIA: This study included all obstetrical randomized controlled trials that reported clinical outcomes for both participants and nonparticipants. METHODS: The primary outcome captured the presence of morbidity. It was a composite of the primary outcome of each study comparing the participant arm with the nonparticipant arm. If a primary outcome was not clearly defined, a surrogate was developed on the basis of the core outcomes for the clinical condition studied. The risk of bias was assessed with the Newcastle-Ottawa Scale. Subgroup analyses for relevant obstetrical and neonatal outcomes were performed. The summary comparisons were reported as odds ratios with 95% confidence intervals computed using random-effects meta-analysis with heterogeneity evaluated using the I2 statistic. A funnel plot was used to examine publication bias, and there was no asymmetry. RESULTS: After reviewing more than 1100 abstracts, 17 obstetrical randomized controlled trials (103,610, with 26,293 participants and 77,317 nonparticipants) met our inclusion criteria and were analyzed. Of note, 9 studies were not rated as high quality, primarily for failing to control for confounding factors. Trial interventions were categorized as antepartum (n=11), intrapartum (n=5), or postpartum (n=1). Overall, participants in obstetrical randomized controlled trials had no difference in outcomes compared with nonparticipants (n=17: odds ratio, 0.88; 95% confidence interval, 0.52-1.49; I2=90%). Moreover, there was no difference seen when only randomized controlled trials that reported a primary outcome were included (n=12: odds ratio, 0.76; 95% confidence interval, 0.38-0.1.49; I2=93%). In addition, there was no difference noted in the subgroup where the randomized controlled trial intervention was not available to nonparticipants (n=7: odds ratio, 0.91; 95% confidence interval, 0.45-1.85; I2=68%). CONCLUSION: Pregnant individuals who agreed to participate in randomized controlled trials had no difference in outcomes compared with those who decline participation. Pregnant individuals should be provided with this reassuring information when offered to participate in a randomized controlled trial. Moreover, this information may improve patient recruitment into randomized controlled trials.

COVID-19 vaccine and pregnancy outcomes: A systematic review and meta-analysis.

OBJECTIVES: To explore perinatal outcomes in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-vaccinated pregnant women compared with unvaccinated counterparts. METHODS: Search was conducted using Web of Science, Scopus, ClinicalTrial.gov, MEDLINE, Embase, OVID, and Cochrane Library as electronic databases. We included observational studies evaluating pregnant women undergoing SARS-CoV-2 vaccination and compared pregnancy and perinatal outcomes with those in unvaccinated women. Categorical variables were assessed using odds ratio (OR) with 95% confidence interval (CI), whereas for continuous variables, the results were expressed as mean difference with their 95% CI. All analyses were performed by adopting the random effect model of DerSimonian and Laird. RESULTS: There was no difference in the probability of having a small-for-gestational-age fetus (OR 0.97, 95% CI 0.85-1.09; P = 0.570), but we observed a reduced probability of a non-reassuring fetal monitoring, a reduced gestational age at delivery, and a reduced probability of premature delivery in vaccinated pregnant women versus unvaccinated ones. CONCLUSION: The probability of small for gestational age is similar between vaccinated and unvaccinated pregnant women, and the former also had a slightly reduced rate of premature delivery.