No abstract

Enlargement of the LA volume with unchanged blood pressure values, as found using RT3DE, may be part of the adaptation to increased blood volume during pregnancy.

BackgroundThe ratio between the fetal umbilical artery pulsatility index (UA-PI) and the middle cerebral artery pulsatility index (MCA-PI) is termed the cerebroplacental ratio (CPR). The CPR represents fetal blood flow redistribution at the early stages of placental insufficiency; moreover, it has predictive value for adverse intrapartum and neonatal outcomes. However, internationally accepted reference ranges for CPR are lacking.ObjectiveThis study sought to establish UA-PI, MCA-PI, and CPR reference ranges in low-risk, normal-growth singleton fetuses during the third trimester of pregnancy.MethodsA retrospective cohort cross-sectional study was performed in the obstetrics ultrasound unit of a university hospital in Israel. We reviewed all fetal and maternal electronic records of pregnant women referred for ultrasound assessment during the third trimester between January 2014 and January 2019. We included only singleton pregnancies with normal anatomy scans and a normal third-trimester estimated fetal weight. The UA-PI, MCA-PI, and CPR reference ranges were reconstructed for each of the vessels for each gestational age between 29 and 41 weeks.ResultsA total of 560 pregnancies met the inclusion criteria. Satisfactory waveforms and measurements were obtained in all cases. At least 18 women enrolled at each gestational week. The MCA-PI and CPR values showed a similar parabolic curve during the third trimester of pregnancy, with a peak value at 32 and 33 gestational weeks, respectively. The UA-PI showed a linear and gradual decrease over the gestational age.ConclusionsIn this study we established UA-PI, MCA-PI, and CPR reference ranges in low-risk, normal-growth singleton fetuses during the third trimester based on the Israeli population.

Severe iodine deficiency during pregnancy has substantial hormonal consequences, such as fetal brain damage. Data on the potential effects of mild-to-moderate iodine deficiency on the thyroid function of pregnant women and their newborns are scarce and divergent. We investigated the association between iodine intake in pregnancy and maternal and neonatal thyroid function in a region with mild-to-moderate iodine deficiency. Pregnant women’s iodine status was evaluated using an iodine food frequency questionnaire, serum thyroglobulin (Tg), and urinary iodine concentration (UIC). Neonatal thyrotropin (nTSH) values were measured after birth. Obstetrics and anthropometric data were also collected. Among the 178 women (median age 31 years) included in the study, median (interquartile range) estimated dietary iodine intake, Tg and UIC were 179 (94–268) μg/day, 18 (11–33) μg/L, and 60 (41–95) μg/L, respectively. There was a significant inverse association of iodine intake with Tg values among the study population (β = −0.2, F = 7.5, p < 0.01). Women with high free triiodothyronine (FT3) values were more likely to exhibit an estimated iodine intake below the estimated average requirement (160 μg/day, odds ratio [OR] = 2.6; 95% confidence interval [CI], 1.1–6.4; p = 0.04) and less likely to consume iodine-containing supplements (OR = 0.3, 95% CI, 0.1–0.8; p = 0.01). It is possible that thyroid function may be affected by iodine insufficiency during pregnancy in regions with mild-to-moderate iodine deficiency. The relatively small sample size of the studied population warrants further investigation.