Polyhydramnios and adverse perinatal outcome – what is the actual cutoff?

Risk of intrapartum cesarean delivery in twin pregnancies: A retrospective cohort study

OBJECTIVE

To compare the risk of intrapartum cesarean delivery (CD) between patients with twin and singleton pregnancies undergoing a trial of labor and identify risk factors for intrapartum CD in twin pregnancies.

METHODS

The present study was a retrospective cohort study of patients with a twin or singleton pregnancy who underwent a trial of labor at ≥340/7 weeks in a single center (2015-2022). The primary outcome was the rate of intrapartum CD. In twin pregnancies, this outcome was limited to CD of both twins. The association of plurality with intrapartum CD was estimated using multivariable Poisson regression.

RESULTS

A total of 20 754 patients met the study criteria, 669 of whom had a twin pregnancy. Patients with twins had a greater risk of intrapartum CD (of both twins) than those with singleton pregnancies (22.1% vs 15.9%, respectively; aRR 1.38 [95% CI: 1.15-1.66]), primarily due to a greater risk of failure to progress. In addition, 4.1% of the twin pregnancies had a CD for the second twin, resulting in an overall CD rate in twin pregnancies of 26.2%. Variables associated with intrapartum CD in twin pregnancies included nulliparity (aOR 3.50, 95% CI: 2.34-5.25), birthweight discordance >20% (aOR 2.47, 95% CI: 1.27-4.78), and labor induction (aOR 1.64, 95% CI: 1.07-2.53). The rate of intrapartum CD was highest when all three risk factors were present (67% [95% CI: 41%-87%]).

CONCLUSION

Twin pregnancies are associated with a greater risk of intrapartum CD than singleton pregnancies. Information on the individualized risk of intrapartum CD may be valuable when counseling patients with twins regarding mode of delivery.

Window to the Womb: Amniotic Fluid and Postnatal Outcomes

Amniotic fluid volumes are tightly regulated, and amniotic fluid derangement can indicate maternal complications or fetal abnormalities. Ultrasound estimate of amniotic fluid provides a tool to evaluate the maternal-fetal-placental interface in real-time. Oligohydramnios and polyhydramnios are associated with adverse maternal and neonatal outcomes. Oligohydramnios is associated with adverse maternal and neonatal outcomes including cesarean delivery, operative vaginal delivery, induction of labor, postpartum hemorrhage, small for gestational age neonate, intrauterine demise, neonatal death, NICU admission, and APGAR less than 7 at. 5 minutes of life Polyhydramnios is associated with adverse outcomes including cesarean delivery, induction of labor, placental abruption, shoulder dystocia, cord prolapse, postpartum hemorrhage, intrauterine fetal demise, NICU admission, neonatal death, APGAR less than 7 at 5 minutes of life, large for gestational age neonate, and respiratory distress syndrome. Therefore, Amniotic fluid should be evaluated when maternal or fetal well-being is in question.

Term Idiopathic Polyhydramnios, and Labor Complications

Background and Aim: Polyhydramnios is associated with an increased risk of various adverse pregnancy outcomes, yet complications during labor have not been sufficiently studied. We assessed the labor and perinatal outcomes of idiopathic polyhydramnios during term labor. Methods: Retrospective cohort study at a tertiary medical center between 2010 and 2014. Women with idiopathic polyhydramnios defined as an amniotic fluid index (AFI) greater than 24 cm or a deep vertical pocket (DVP) > 8 cm (cases) were compared with women with a normal AFI (5-24 cm) (controls). Statistics: Descriptive, means ± SDs, medians + IQR. Comparisons: chi-square, Fisher's exact test, Mann-Whitney Test, multivariate logistic models. Results: During the study period 11,065 women had ultrasound evaluation completed by a sonographer within two weeks of delivery. After excluding pregnancies complicated by diabetes (pre-gestational or gestational), fetal anomalies, IUFD, multifetal pregnancies, elective cesarean deliveries (CD) or missing data, we included 750 cases and 7000 controls. The degree of polyhydramnios was mild in 559 (75.0%) cases (AFI 24-30 cm or DVP 8-12 cm), moderate in 137 (18.0%) cases (30-35 cm or DVP 12-15 cm) and severe in 54 (7.0%) cases (AFI >35 cm or DVP > 15 cm). Idiopathic polyhydramnios was associated with a higher rate of CD 9.3% vs. 6.2%, p = 0.004; a higher rate of macrosomia 22.8% vs. 7.0%, p < 0.0001; and a higher rate of neonatal respiratory complications 2.0% vs. 0.8%, p = 0.0001. A multivariate regression analysis demonstrated an independent relation between polyhydramnios and higher rates of CD, aOR 1.62 (CI 1.20-2.19 p = 0.002) and composite adverse neonatal outcome aOR 1.28 (CI 1.01-1.63 p = 0.043). Severity of polyhydramnios was significantly associated with higher rates of macrosomia and CD (p for trend <0.01 in both). Conclusions: The term idiopathic polyhydramnios is independently associated with macrosomia, CD and neonatal complications. The severity of polyhydramnios is also associated with macrosomia and CD.

Incidental finding of meconium-stained amniotic fluid in elective cesarean deliveries: Features and perils

OBJECTIVE

To characterize pregnancies in which meconium-stained amniotic fluid (MSAF) was incidentally discovered during elective caesarean delivery (CD), and to evaluate the association with adverse neonatal outcomes.

METHODS

A retrospective study was performed on all patients who underwent elective CD with singleton pregnancies between March 2011 and June 2020. Data analyzed included maternal, pregnancy, and neonatal characteristics. A comparison was made between pregnancies with clear amniotic fluid, MSAF, and thick MSAF.

RESULTS

During the study period, 10 445 patients with singleton pregnancies underwent elective CD. Of them, 368 (3.5%) had MSAF and 31 (0.3%) had thick MSAF. Patients with MSAF gained more weight during pregnancy and suffered more from diabetes compared with patients with clear fluid. Significantly more pregnancies with MSAF had either oligohydramnios or polyhydramnios. Pregnancies in the thick-MSAF group had more intrahepatic cholestasis of pregnancy. No differences were found between the groups in the composite adverse neonatal outcome, including 5-min Apgar score, need for mechanical ventilation, and admission to the neonatal intensive care unit.

CONCLUSION

The incidental finding of MSAF during elective CD is not associated with increased risks of adverse neonatal outcomes.

Prenatal exposure to isolated amniotic fluid disorders and the risk for long-term cardiovascular morbidity in the offspring

Amniotic fluid (AF) abnormalities are often associated with short-term adverse pregnancy outcomes, including cardiovascular-related. We sought to assess whether in utero exposure to AF abnormalities increases the risk for long-term cardiovascular morbidity of the offspring. We examined the incidence of cardiovascular disorders in singletons exposed and non-exposed to isolated oligohydramnios or polyhydramnios. Cardiovascular morbidity was assessed up to the age of 18 years according to a predefined set of ICD-9 codes. A Kaplan-Meier survival curves were used to compare cumulative morbidity incidence. A Cox proportional hazards model was constructed to control for confounders. During the study period, 195,943 newborns met the inclusion criteria, of which 2.0% (n = 4063) were in pregnancies diagnosed with isolated oligohydramnios and 2.9% (n = 5684) in pregnancies with isolated polyhydramnios. Children exposed to isolated AF disorders had significantly higher rates of long-term cardiovascular morbidity (p=.042). Children exposed to isolated oligohydramnios had higher cumulative incidence of cardiovascular morbidity (log-rank test p=.026) compared to unexposed children, opposing to what was demonstrate when comparing polyhydramnios vs. normal AFV (log-rank test p=.749). In the Cox regression model, while controlling for confounders, isolated oligohydramnios were found to be independently associated with long-term cardiovascular morbidity of the offspring.

Prenatal exposure to isolated amniotic fluid disorders and the risk for long-term endocrine morbidity of the offspring

BACKGROUND

Amniotic fluid abnormalities may be associated with adverse perinatal outcomes, some of which are endocrine related.

OBJECTIVE

To evaluate whether in utero exposure to amniotic fluid abnormalities is associated with long-term endocrine morbidity in the offspring.

STUDY DESIGN

In this cohort study, the incidence of long-term endocrine disorders was compared between singletons exposed and non-exposed to oligohydramnios or polyhydramnios.

RESULTS

During the study period, 195 943 newborns were included in the study, of them 2.0% (n = 4072) and 2.9% (n = 5684) were exposed to oligohydramnios and polyhydramnios, respectively. Long-term endocrine morbidity was higher among children exposed to isolated amniotic fluid disorders, as was also noted in the Kaplan-Meier survival curve (log-rank test p < 0.001). Abnormal amniotic fluid volume was found to be independently associated with long-term endocrine morbidity of the offspring according to a Cox regression model controlled for clinically related confounders.

CONCLUSION

In utero exposure to isolated amniotic fluid abnormalities is independently associated with long-term endocrine morbidity in the offspring.

The effect of fertility treatment on adverse perinatal outcomes in women aged at least 40 years

OBJECTIVE

To compare perinatal outcomes between spontaneous conception and assisted reproductive technologies (ART) among patients of advanced maternal age.

METHODS

The present retrospective study included data from singleton pregnancies of women aged at least 40 years who delivered between January 1, 1991, and December 31, 2013, at Soroka University Medical Center, Beer Sheva, Israel. Demographic, obstetric, and perinatal data were compared between pregnancies conceived with ART (in vitro fertilization [IVF] or ovulation induction) and those conceived spontaneously. Multiple regression models were used to define independent predictors of adverse outcomes.

RESULTS

A total of 8244 singleton pregnancies were included; 229 (2.8%) following IVF, 86 (1.0%) following ovulation induction, and 7929 (96.2%) were spontaneous. Preterm delivery (P<0.001), fetal growth restriction (FGR) (P<0.001), and cesarean delivery (P<0.001) demonstrated linear associations with the conception mode; the highest rates for each were observed for IVF, with decreased rates for ovulation induction and spontaneous conception. The incidence of gestational diabetes and hypertensive disorders were highest among pregnancies following ART. No association was observed between conception mode and perinatal mortality. Multivariate logistic regression demonstrated that IVF was independently associated with increased odds of preterm delivery (P<0.001) and FGR (P=0.027) compared with spontaneous conception.

CONCLUSIONS

Among patients of advanced maternal age, ART were independently associated with increased FGR and preterm delivery rates compared with spontaneous pregnancies; perinatal mortality was comparable.

Amniotic Fluid Assessment: Amniotic Fluid Index Versus Maximum Vertical Pocket

Amniotic fluid assessment is vital to fetal well-being. Accurately diagnosing an amniotic fluid abnormality can aid in the proper management of a pregnancy at risk for an adverse outcome. Sonography is the most common way to assess amniotic fluid volume throughout a pregnancy; however, the most accurate technique, amniotic fluid index or maximum vertical pocket, is yet to be determined. Dye-dilution techniques are the most accurate way to measure amniotic fluid volume, but they are invasive and can be performed only at the time of a cesarean delivery. Multiple studies have been performed to determine the accuracy of the amniotic fluid index and maximum vertical pocket methods when diagnosing amniotic fluid volume abnormalities. Based on the studies reviewed in this article, neither method stands out as superior to the other when it comes to diagnosing amniotic fluid abnormalities during pregnancy. However, the maximum vertical pocket should also always be considered when an amniotic fluid abnormality is suspected because the amniotic fluid index overdiagnoses amniotic fluid abnormalities, leading to increased rates of pregnancy intervention and the potential for adverse pregnancy outcomes.

Outcomes From Polyhydramnios With Normal Ultrasound

OBJECTIVE

To investigate the short- and long-term outcomes of children from pregnancies complicated with polyhydramnios, defined as amniotic fluid index (AFI) >24 cm, and with a normal detailed ultrasound examination.

METHODS

This retrospective cohort study examined 134 children aged 4 to 9 years with polyhydramnios and normal detailed ultrasound examination during pregnancy compared with 268 controls with normal AFI and normal detailed ultrasound examination matched for maternal age, year of delivery, gestational week at delivery, and presence or absence of diabetes. The primary outcome was the rate of malformations diagnosed postnatally. Additional outcomes were obstetrics outcomes, genetic syndromes, and neurodevelopment.

RESULTS

Polyhydramnios was associated with increased risk for cesarean delivery (CD) and birth weight >90th percentile. This elevation in CD was attributed to increased rate of elective CD due to suspected macrosomia. Polyhydramnios was associated with increased risk for congenital malformations (n = 25 [19%] compared with 27 [10%], respectively; P = .016) without a statistically significant increase in the rate of major malformations (11 [8%] vs. 10 [4%]; P = .057). Genetic syndromes were more prevalent in the polyhydramnios group (5 [3.7%] vs. 2 [0.75%]; P = .043), as were neurologic disorders and developmental delay (9.7% vs. 3%; P = .004).

CONCLUSIONS

Despite a normal detailed ultrasound examination, polyhydramnios is associated with increased rate of fetal malformations, genetic syndromes, neurologic disorders, and developmental delay, which may be diagnosed only after birth.