Prenatal diagnosis of polycystic kidney caused by biallelic hypomorphic variants in the PKD1 gene.

Heterozygous loss-of-function variants in the PKD1 gene are commonly associated with adult-onset autosomal dominant polycystic kidney disease (ADPKD), where the formation of renal cysts depends on the dosage of the PKD1 gene. Biallelic null PKD1 variants are not viable, but biallelic hypomorphic variants could lead to early-onset PKD. We report a non-consanguineous Chinese family with recurrent fetal polycystic kidney and negative findings in the coding region of the PKHD1 gene or chromosomal microarray analysis. Trio exome analysis revealed compound heterozygous variants of uncertain significance in the PKD1 gene in the index pregnancy: a novel paternally inherited c.7863 + 5G > C and a maternally inherited c.9739C > T, p.(Arg3247Cys). Segregation analysis through long-range PCR followed by nested PCR and Sanger sequencing confirmed another affected fetus had both variants, while the other two normal siblings and the parents carried either variant. Thus, these two variants, both of which were hypomorphic as opposed to null variants, co-segregated with prenatal onset polycystic kidney disease in this family. Functional studies are needed to further determine the impact of these two variants. Our findings highlight the biallelic inheritance of hypomorphic PKD1 variants causing prenatal onset polycystic kidney disease, which provides a better understanding of phenotype-genotype correlation and valuable information for reproductive counseling.

Prediction of labour outcomes using prelabour computerised cardiotocogram and maternal and fetal Doppler indices: A prospective cohort study.

OBJECTIVES: To investigate the association and the potential value of prelabour fetal heart rate short-term variability (STV) determined by computerised cardiotocography (cCTG) and maternal and fetal Doppler in predicting labour outcomes. DESIGN: Prospective cohort study. SETTING: The Prince of Wales Hospital, a tertiary maternity unit, in Hong Kong SAR. POPULATION: Women with a term singleton pregnancy in latent phase of labour or before labour induction were recruited during May 2019-November 2021. METHODS: Prelabour ultrasonographic assessment of fetal growth, Doppler velocimetry and prelabour cCTG monitoring including Dawes-Redman CTG analysis were registered shortly before induction of labour or during the latent phase of spontaneous labour. MAIN OUTCOME MEASURES: Umbilical cord arterial pH, emergency delivery due to pathological CTG during labour and neonatal intensive care unit (NICU)/special care baby unit (SCBU) admission. RESULTS: Of the 470 pregnant women invited to participate in the study, 440 women provided informed consent and a total of 400 participants were included for further analysis. Thirty-four (8.5%) participants underwent emergency delivery for pathological CTG during labour. A total of 6 (1.50%) and 148 (37.00%) newborns required NICU and SCBU admission, respectively. Middle cerebral artery pulsatility index (MCA-PI) and MCA-PI z-score were significantly lower in pregnancies that required emergency delivery for pathological CTG during labour compared with those that did not (1.23 [1.07-1.40] versus 1.40 [1.22-1.64], p = 0.002; and 0.55 ± 1.07 vs. 0.12 ± 1.06), p = 0.049]. This study demonstrated a weakly positive correlation between umbilical cord arterial pH and prelabour log10 STV (r = 0.107, p = 0.035) and the regression analyses revealed that the contributing factors for umbilical cord arterial pH were smoking (p = 0.006) and prelabour log10 STV (p = 0.025). CONCLUSIONS: In pregnant women admitted in latent phase of labour or for induction of labour at term, prelabour cCTG STV had a weakly positive association with umbilical cord arterial pH but was not predictive of emergency delivery due to pathological CTG during labour.

Intrauterine fetal death followed by shoulder dystocia and birth by modified posterior axillary sling method: a case report.

BACKGROUND: Various manoeuvres such as McRoberts position, suprapubic pressure, rotational methods, posterior arm extraction and all-four position (HELPERR) have been proposed for relieving shoulder dystocia with variable success. Posterior axillary sling method using a rubber catheter was proposed in 2009 but has not been widely used. We modified this method using ribbon gauzes and a long right-angle forceps and report a successful case. CASE PRESENTATION: A 44 years old parity one Chinese woman with a history of a caesarean delivery and poorly controlled type 2 diabetes mellitus was admitted to the Accident and Emergency Department for advanced stage of labour at term. Upon arrival, intrauterine fetal demise was diagnosed with severe asynclitism causing obstruction at the perineum. Episiotomy resulted in birth of the fetal head. The fetal posterior right shoulder, however, remained very high up in the pelvis and HELPERR methods failed to extract the shoulders. We then tied two long ribbon gauzes together, and guided its knot to the anterior aspect of the posterior axilla. By using a long right-angle forceps (24 cm long) to grasp the knot on the posterior side of the axilla and pulling it through, a sling was formed. Traction was then applied through the sling to simultaneously pull and rotate the posterior shoulder. A stillbirth of 3488 g was finally extracted. CONCLUSIONS: We modified the sling method by using two ribbon gauzes, tied together and a right-angle forceps with several advantages. Compared to a rubber catheter, ribbon gauze with a knot can be easily held between the fingers for easy guidance past the fetal axilla. It is also thin, non-elastic and stiff enough to ensure a good grip for traction. The long and slim design of the right-angle forceps makes it easy to pass through a narrow space and reach the axilla high up in the pelvis. We emphasize simultaneous traction and rotation, so that the shoulders are delivered through the wider oblique pelvic outlet dimension.

Umbilical cord prolapse: revisiting its definition and management.

Umbilical cord prolapse is an unpredictable obstetrical emergency with an incidence ranging from 1 to 6 per 1000 pregnancies. It is associated with high perinatal mortality, ranging from 23% to 27% in low-income countries to 6% to 10% in high-income countries. In this review, we specifically addressed 3 issues. First, its definition is not consistent in the current literature, and "occult cord prolapse" is a misnomer because the cord is still above the cervix. We proposed that cord prolapse, cord presentation, and compound cord presentation should be classified according to the positional relationship among the cord, the fetal presenting part, and the cervix. All of them may occur with either ruptured or intact membranes. The fetal risk is highest in cord prolapse, followed by cord presentation, and lastly by compound cord presentation, which replaces the misnomer "occult cord prolapse." Second, the mainstay of treatment of cord prolapse is urgent delivery, which means cesarean delivery in most cases, unless vaginal delivery is imminent. The urgency depends on the fetal heart rate pattern, which can be bradycardia, recurrent decelerations, or normal. It is most urgent in cases with bradycardia, because a recent study showed that cord arterial pH declines significantly with the bradycardia-to-delivery interval at a rate of 0.009 per minute (95% confident interval, 0.0003-0.0180), and this may indicate an irreversible pathology such as vasospasm or persistent cord compression. However, cord arterial pH does not correlate with either deceleration-to-delivery interval or decision-to-delivery interval, indicating that intermittent cord compression causing decelerations is reversible and less risk. Third, while cesarean delivery is being arranged, different maneuvers should be adopted to relieve cord compression by elevating the fetal presenting part and to prevent further cord prolapse beyond the vagina. A recent study showed that the knee-chest position provides the greatest elevation effect, followed by filling of the maternal urinary bladder with 500 mL of fluid, and then the Trendelenburg position (15°) and other maneuvers. However, each maneuver has its own advantages and limitations; thus, they should be applied wisely and with great caution, depending on the actual clinical situation. Therefore, we have proposed an algorithm to guide this acute management.