Risk factors for term or near-term fetal growth restriction in the absence of maternal complications

Maternal Plasma Choline during Gestation and Small for Gestational Age Infants

OBJECTIVE

Small for gestational age (SGA) infants are at increased risk for neonatal morbidity and developmental problems in childhood. No current interventions during human pregnancy address this problem. This study investigated the possible relationship between maternal choline concentration during pregnancy and SGA infants.

STUDY DESIGN

Maternal plasma choline concentrations were sampled at 16 and 28 weeks' gestation from women in a public prenatal clinic. Additional factors assessed were maternal age, body mass index, infection, C-reactive protein, hair cortisol, and compliance with prenatal vitamins and folate. Infants below the 10th percentile for gestational age were classified as SGA. Binary logistic regression was used to identify significant associated factors in pregnancies resulting in SGA infants compared with pregnancies resulting in non-SGA infants.

RESULTS

Thirteen (8%) of 159 women had SGA infants. Maternal plasma choline concentrations were low for pregnant participants whose infants were SGA, with the 28-week concentration significantly lower compared with other participants. Plasma choline concentrations ≥7 μM at 28 weeks, consistent with a minimally adequate dietary intake of choline-containing foods, were achieved by only 2 (15%) of mothers with SGA infants, compared with 51% of mothers whose infants were not SGA. Choline concentrations <7 μM at 28 weeks' gestation were associated with an odds ratio for SGA of 16.6 (95% confidence interval: 1.5-189.2, p = 0.023). Other significant factors were female sex and maternal C-reactive protein plasma concentration during gestation.

CONCLUSION

This observational study suggests that higher maternal choline levels may influence the risk for SGA. Maternal plasma choline concentrations are not routinely available in clinical laboratories. However, plasma choline levels can be increased by the mothers' intake of choline or phosphatidylcholine supplements. No nutritional intervention is currently recommended to prevent SGA, but the evidence from this study suggests that further consideration of the role of maternal choline may be warranted.

KEY POINTS

· More females are small for gestational age.. · Low maternal choline is related to small infants.. · Maternal choline ≥7 μM at 28 weeks appears optimal..

Maternal Factors for Intrauterine Growth Retardation: Systematic Review and Meta-Analysis of Observational Studies

Intrauterine growth retardation (IUGR) is a major complication of pregnancy and is the second leading cause of perinatal morbidity and mortality. The etiology of IUGR is multifactorial and the maternal factors are easily identifiable and modifiable. The present study aimed to perform a meta-analysis to identify the association between various maternal factors and IUGR. Eight electronic databases (PubMed, Cochrane, Embase, CIHNAL Plus, CNKI, VIP database, CBM, and WanFang database) were searched from their inception until July 2020. Eligibility screening, data extraction, and quality assessment of the retrieved articles were conducted independently by two reviewers. The Newcastle-Ottawa Quality Assessment Form and the Joanna Briggs Institute critical appraisal tool were used to evaluate the quality of included studies. The outcomes of study were calculated by OR with 95%CI. The study protocol was registered with PROSPERO (No. CRD42020210615). A total of 15 studies were included, with a sample size range from 152 to 9372. The quality of included studies ranged from moderate to high. The pooled results identified seven factors: smoking (OR = 1.62, 95%CI 1.38-1.90), primiparity (OR = 1.64, 95%CI 1.20-2.24), and prepregnancy.BMI < 18.5 (OR = 1.98, 95%CI 1.29-3.03), anemia (OR = 2.01, 95%CI 1.44-2.82), hypoproteinemia (OR = 2.91, 95%CI 1.94-4.36), pregnancy-induced hypertension (OR = 3.45, 95%CI 1.80-6.58), and maternal gestational weight gain (OR = 2.51, 95%CI 1.88-3.35). The present study identified several maternal factors for IUGR: smoking, primiparity, prepregnancy BMI < 18.5, poor gestational weight gain, PIH, anemia, and hypoproteinemia. The result could serve to generate risk factors prediction models, improve the management and education for child-bearing or early pregnant women.

Sex Differences Are Here to Stay: Relevance to Prenatal Care

Sex differences exist in the incidence and presentation of many pregnancy complications, including but not limited to pregnancy loss, spontaneous preterm birth, and fetal growth restriction. Sex differences arise very early in development due to differential gene expression from the X and Y chromosomes, and later may also be influenced by the action of gonadal steroid hormones. Though offspring sex is not considered in most prenatal diagnostic or therapeutic strategies currently in use, it may be beneficial to consider sex differences and the associated mechanisms underlying pregnancy complications. This review will cover (i) the prevalence and presentation of sex differences that occur in perinatal complications, particularly with a focus on the placenta; (ii) possible mechanisms underlying the development of sex differences in placental function and pregnancy phenotypes; and (iii) knowledge gaps that should be addressed in the development of diagnostic or risk prediction tools for such complications, with an emphasis on those for which it would be important to consider sex.

Unfavorable influence of prematurity on the neonatal prognostic of small for gestational age fetuses

Vascular stress at the level of the uterus-placental unit, with chronic placental ischemia, results in intrauterine growth restriction. Expectation management can be used, when the situation allows, in cases of compensated intrauterine growth restriction. The aim of the present study was to evaluate the neonatal prognosis of preterm births with and without growth restriction and term births with growth restriction in order to improve decisional accuracy regarding the termination of pregnancy. The frequency of term birth infants with low birth weight for gestational age was ~2%. The male sex, predominated only in the group of premature infants with normal weight for the gestational age. The highest frequency of neonatal complications studied occurred in the group of preterm neonates small for gestational age (SGA) with statistical significance obtained for cardiovascular arrest acute respiratory failure, ulcer-necrotic enterocolitis, respiratory distress, cerebral edema, intraventricular hemorrhage, cerebral hemorrhage, pulmonary hemorrhage, neonatal infection, hypoglycemia, retinopathy, anemia, hemorrhagic disease, disseminated intravascular coagulation, disease of hyaline membranes, neonatal sepsis, need for intensive neonatal therapy and death. In conclusion, immediate neonatal adaptation of SGA preterm neonates is more deficient than for preterm neonates with appropriate weight for gestational age; the adaptation of preterm neonates, in turn, is more deficient than term newborns with intrauterine growth restriction. The term newborns with intrauterine growth restriction have a neonatal adaptation comparable to that of the term newborns with weight corresponding to the gestational age.

Periconceptional multivitamin use and risk of preterm or small-for-gestational-age births in the Danish National Birth Cohort

BACKGROUND

The intake of periconceptional multivitamins may decrease the risk of preterm births (PTBs) or small-for-gestational-age (SGA) births.

OBJECTIVE

We related the timing and frequency of periconceptional multivitamin use to SGA births and PTBs and its clinical presentations (ie, preterm labor, premature rupture of membranes, and medical induction).

DESIGN

Women in the Danish National Birth Cohort (n = 35,897) reported the number of weeks of multivitamin use during a 12-wk periconceptional period. Cox regression was used to estimate the relation between any multivitamin use and PTBs (<37 wk) or SGA births (birth weight adjusted for gestational age >2 SDs below the mean on the basis of fetal growth curves). The timing (preconception and postconception) and frequency of use were also analyzed. Regular users (4-6 wk) and partial users (1-3 wk) in each period were compared with nonusers.

RESULTS

The association between periconceptional multivitamin use and PTBs varied according to prepregnancy overweight status (P-interaction = 0.07). Regular preconception and postconception multivitamin use in women with a prepregnancy BMI (in kg/m(2)) <25 was associated with reduced risks of a PTB (HR: 0.84; 95% CI: 0.73, 0.95) and preterm labor (HR: 0.80; 95% CI: 0.69, 0.94). No similar associations were shown for overweight women. The adjusted risk of an SGA birth was reduced in multivitamin users regardless of their prepregnancy BMI (HR: 0.83; 95% CI: 0.73, 0.95), with the strongest association in regular users in the postconception period.

CONCLUSION

Regular periconceptional multivitamin use was associated with reduced risk of SGA births and PTBs in nonoverweight women.

Anxiety and optimism associated with gestational age at birth and fetal growth

Psychosocial factors such as anxiety or optimism may be related to the risk of adverse pregnancy outcomes, but the evidence is conflicting. We investigated the relation between maternal anxiety, optimism, gestational age and infant birth weight in a cohort of 667 nulliparous women from the Prenatal Exposures and Preeclampsia Prevention study, Pittsburgh PA. Women completed the Spielberger Trait Anxiety Inventory and the Life Orientation Test at 18 weeks gestation. Linear and logistic regression models assessed the relation of anxiety and optimism to gestational age, birth weight centile, preterm delivery (<37 weeks) or small for gestational age (<10th percentile) births. After adjustment for age, race, preeclampsia, and smoking, higher anxiety was associated with decreasing gestational age (-1.6 days per SD increase in anxiety score, P = 0.06). This relationship was modified by maternal race (P < 0.01 for interaction). Among African American women, each SD increase in anxiety was associated with gestations that were, on average, 3.7 days shorter (P = 0.03). African American women with anxiety in the highest quartile had gestations that were 8.2 days shorter, and they had increased risk for preterm birth after excluding cases of preeclampsia (OR 1.69, 95% CI 1.08, 2.64). There was no association between anxiety and gestational age among White women. There was also no relation between anxiety, optimism and birth weight centile. Trait anxiety was associated with a reduction in gestational age and increased risk for preterm birth among African American women. Interventions that reduce anxiety among African American pregnant women may improve pregnancy outcomes.

Annexin A5 levels in midtrimester amniotic fluid: association with intrauterine growth restriction

OBJECTIVE

The purpose of this study was to determine whether amniotic fluid levels of annexin A5 (AF-AnxA5) may be associated with intrauterine growth restriction (IUGR).

STUDY DESIGN

Amniotic fluid was obtained in a cohort of pregnant patients (n = 172) undergoing amniocentesis at 15 to 24 weeks' gestation and annexin A5 (AnxA5) levels were determined with enzyme-linked immunosorbent assay (ELISA). Patients who developed IUGR were compared with the remainder of the cohort.

RESULTS

AF-AnxA5 levels significantly increased through gestation (P = .003). The mean level of AF-AnxA5 in IUGR patients (n = 15) was significantly higher (P = .028) than in the remainder of the cohort (n = 130). Elevated AF-AnxA5 > 20 ng/mL was associated with a relative risk of 3.5 for the development of IUGR (P = .023).

CONCLUSION

AnxA5 is present in amniotic fluid and increases through gestation from 15 to 24 weeks. Elevated AF-AnxA5 levels were present in patients who developed IUGR. AF-AnxA5 may be a useful marker for identifying pregnancy abnormalities.