Maternal malnutrition during pregnancy among women with sickle cell disease.

OBJECTIVE: The objective of this study was to compare the nutritional status and dietary intake of pregnant women with sickle cell disease (SS hemoglobinopathy and SC hemoglobinopathy) to healthy controls and report the maternal and perinatal outcomes. METHODS: This is a prospective, longitudinal cohort study. Pregnant women with a diagnosis of sickle cell disease and control group were recruited in an outpatient clinic of a tertiary care hospital in São Paulo, Brazil. Maternal anthropometric data and dietary intake data were collected at the second and third trimesters. RESULTS: A total of 49 pregnancies complicated by sickle cell disease were included. Prepregnancy body mass index was significantly lower in the SS hemoglobinopathy group (n=26, median 20.3 kg/m2) than the SC hemoglobinopathy group (n=23, 22.7 kg/m2) or control group (n=33, 23.2 kg/m2, p<0.05). The prepregnancy nutritional status revealed significantly more women classified as underweight in the SS hemoglobinopathy group (15.4%) than in the SC hemoglobinopathy group (4.4%) and control group (1.6%, p=0.009). In the second trimester, maternal protein intake was significantly lower in SS hemoglobinopathy (73.2 g/day) and SC hemoglobinopathy (68.8 g/day) than in the control group (95.7 g/day, p=0.004). In the third trimester, only SS hemoglobinopathy mothers showed dietary intake of protein significantly lower than that of the controls (67.5 g/day vs. 92.8 g/day, p=0.02). Vitamin A and E consumption was also reduced in the third trimester in the SS hemoglobinopathy group (p<0.05). CONCLUSION: The nutritional status of pregnant women with SS hemoglobinopathy is characterized by a state of undernutrition. The lower protein intake in the second and third trimesters of pregnant women with SS hemoglobinopathy may contribute to this condition. Undernourishment is a serious complication of sickle cell disease, primarily during pregnancy, and it should be addressed during the prenatal period.

Unplanned pregnancy in Brazil: national study in eight university hospitals.

OBJECTIVE: To estimate the prevalence of unplanned pregnancy in eight public university hospitals, distributed in the five regions that make up Brazil. METHODS: A secondary analysis of a national multicenter cross-sectional study, carried out in eight public university hospitals between June 1 and August 31, 2020, in Brazil. Convenience sample including women who gave birth within sixty consecutive days and met the following criteria: over 18 years old; gestational age over 36 weeks at delivery; with a single and live newborn, without malformations. RESULTS: Sample composed of 1,120 postpartum women, of whom 756 (67.5%) declared that the pregnancy had not been planned. The median prevalence of unplanned pregnancy was 59.7%. The prevalence of unplanned pregnancy across hospitals differed significantly: Campinas (54.8%), Porto Alegre (58.2%), Florianópolis (59%), Teresina (61.2%), Brasília (64.3%), São Paulo (64.6%), Campo Grande (73.9%) and Manaus (95.3%) (p < 0.001). Factors significantly associated with unplanned pregnancy were maternal age, black color, lower family income, greater number of children, greater number of people living in household, and not having a partner. CONCLUSION: In the studied sample, about two thirds of the pregnancies were declared as unplanned. The prevalence of unplanned pregnancies was related to social and demographic factors and varied significantly across the university hospitals evaluated.

Uso de misoprostol em obstetrícia / Misoprostol use in obstetrics

PONTOS-CHAVE O misoprostol é um análogo da prostaglandina E1 (PGE1) que consta na Lista de Medicamentos Essenciais da Organização Mundial da Saúde (OMS) desde 2005 O Brasil possui uma das regulações mais restritivas do mundo relacionadas ao uso do misoprostol, estabelecendo que o misoprostol tem uso hospitalar exclusivo, com controle especial, e venda, compra e propaganda proibidas por lei Atualmente, o misoprostol é a droga de referência para tratamento medicamentoso nos casos de aborto induzido, tanto no primeiro trimestre gestacional quanto em idades gestacionais mais avançadas O misoprostol é uma medicação efetiva para o preparo cervical e indução do parto O misoprostol é um medicamento essencial para o manejo da hemorragia pós-parto

Obstetric simulation for undergraduate medical education: how to improve students' self-confidence and expectation according to gender.

OBJECTIVE: The aim of this study was to evaluate the effects of obstetric simulation training on undergraduate medical students to improve their self-confidence. METHODS: Fifth-year undergraduate medical students were invited to a 2-week course of simulation in obstetrics during their clerkship. The sessions included were as follows: (1) care for the second and third periods of childbirth, (2) partograph analysis and pelvimetry, (3) premature rupture of membranes at term, and (4) diagnosis and management of third-trimester bleeding. Before the first session and at the end of the training period, a questionnaire about self-confidence in obstetric procedures and skills was applied. RESULTS: A total of 115 medical students were included, of whom 60 (52.2%) were male and 55 (47.8%) were female. Comparing initial and final scores, the median results of the subscales "comprehension and preparation" (18 vs. 22, p<0.001), "knowledge of procedures" (14 vs. 20, p<0.001), and "expectation" (22 vs. 23, p<0.01) were significantly higher at the end of the training period in all items of the questionnaire than in the beginning. Differences were found based on the students' gender, i.e., female students had a significantly higher sum of scores than the male students in the initial subscale for "expectation" (median, 24 vs. 22, p<0.001) and "interest" (median, 23 vs. 21, p=0.032), and a higher sum of scores in the subscale for "expectation" (median, 23 vs. 21, p=0.010) in the final questionnaire. CONCLUSION: Obstetric simulation enhances the improvement of students' self-confidence in understanding both the physiology of childbirth and the obstetric care procedures. Further studies are needed to understand the influence of gender on obstetric care.

An enlarged fetal thymus may be the initial response to intrauterine inflammation in pregnant women at risk for preterm birth.

OBJECTIVE: Fetal thymus involvement in prematurity has been studied, and this study aimed to evaluate its relationship with short cervix and amniotic fluid sludge in the second trimester of pregnancy. METHODS: In this prospective cross-sectional study, 79 pregnant women (19+0 to 24+6 weeks) were included, and cervical length and the presence or absence of amniotic fluid sludge were evaluated. In the three-vessel view of the fetal thorax, the thymus was identified, and its perimeter and transverse diameter were measured and transformed to a zeta score based on gestational age. RESULTS: Data from 22 women with short cervix (<25 mm) and 57 patients with normal cervix (≥25 mm) were analyzed. The transverse diameter of the fetal thymus was significantly greater in the short cervix group compared to that of the normal cervix group (z-score 2.708 vs. -0.043, p=0.003). There were no significant differences in the perimeter (z-score -0.039 vs. -0.071, p=0.890) or the transverse diameter (z-score 1.297 vs. -0.004, p=0.091) of the fetal thymus associated with the presence (n=21) or absence of sludge (n=58). CONCLUSION: A short cervix is associated with an increased transverse diameter of the fetal thymus during the second trimester of gestation.

Nonpharmacological Methods to Reduce Pain During Active Labor in A Real-life Setting.

OBJECTIVE: To evaluate the association between pain intensity in the active phase of the first stage of labor with the use or not of nonpharmacological methods for pain relief in a real-life scenario. METHODS: This was an observational cross-sectional study. The variables analyzed were obtained by a questionnaire with the mothers (up to 48 hours postpartum) to investigate the intensity of pain during labor using the visual analog scale (VAS). The nonpharmacological pain relief methods routinely used in obstetric practice were evaluated by consulting medical records. The patients were separated into two groups: Group I - patients who did not use nonpharmacological methods for pain relief and Group II -patients who used these methods. RESULTS: A total of 439 women who underwent vaginal delivery were included; 386 (87.9%) used at least 1 nonpharmacological method and 53 (12.1%) did not. The women who did not use nonpharmacological methods had significantly lower gestational age (37.2 versus 39.6 weeks, p < 0.001) and shorter duration of labor (24 versus 114 min, p < 0.001) than those who used the methods. There was no statistically significant difference in the pain scale score using the VAS between the group that used nonpharmacological methods and the group that did not (median 10 [minimum 2-maximum 10] versus 10 [minimum 6-maximum 10] p = 0.334). CONCLUSION: In a real-life setting, there was no difference in labor pain intensity between the patients who used nonpharmacological methods and those who did not use them during the active phase of labor.

OBJETIVO: Avaliar a associação da intensidade da dor na fase ativa da dilatação do parto em mulheres de acordo com a utilização ou não de métodos não farmacológicos para alívio da dor em cenário de vida real. MéTODOS: Trata-se de um estudo observacional de corte transversal. As variáveis analisadas foram obtidas através de questionário com as puérperas (até 48 horas pós-parto) investigando a intensidade da dor no parto pela escala visual analógica (EVA). As medidas não farmacológicas de alívio da dor, utilizadas rotineiramente na prática obstétrica, foram avaliadas pela consulta aos prontuários. As pacientes foram separadas em dois grupos: Grupo I ­ pacientes que não utilizaram medidas não farmacológicas para alívio da dor e Grupo II - pacientes que utilizaram estas medidas. RESULTADOS: Foram incluídas 439 mulheres que tiveram parto vaginal, sendo que 386 (87,9%) utilizaram, pelo menos, uma medida não farmacológica e 53 (12,1%) não utilizaram. As mulheres que não utilizaram as medidas não farmacológicas apresentaram idade gestacional significativamente menor (37,2 versus 39,6 semanas, p < 0,001) e menor duração do trabalho de parto (24 versus 114 minutos, p < 0,001) quando comparadas às que utilizaram as medidas. Não houve diferença estatisticamente significativa na pontuação da escala da dor pela EVA de acordo com a categorização pelo uso ou não de métodos não farmacológicos (mediana 10 [mínimo 2­máximo 10] versus 10 (mínimo 6­máximo 10), p = 0,334]. CONCLUSãO: Em cenário de vida real, as pacientes submetidas aos métodos não farmacológicos não apresentaram diferença em relação à intensidade da dor quando comparadas às que não os utilizaram durante a fase ativa do trabalho de parto.

Effects of maternal anxiety on fetal and maternal circulation

SUMMARY OBJECTIVE: The aim of this study was to evaluate the association between maternal anxiety in the third trimester and changes in fetal and maternal circulation assessed by Doppler velocimetry. METHODS: This is a prospective, cross-sectional study. The inclusion criteria were good health, a singleton pregnancy, maternal age between 18 and 40 years, and gestational age between 34 and 40 weeks. Doppler measurements included mean uterine artery pulsatility index, fetal middle cerebral artery pulsatility index, peak of systolic velocity, umbilical artery, and umbilical vein. The Beck Anxiety Inventory questionnaire, validated for the Brazilian population, with 21 self-reported items, was applied. RESULTS: The study included 34 pregnant women, and 6 (17.7%) presented a total Beck Anxiety Inventory score showing moderate or severe maternal anxiety. The mean maternal age was 28.1 years (SD 5.7 years); the mean gestational age at interview was 36.5 weeks (SD 1.8 weeks), and the mean Beck Anxiety Inventory total score was 12.3 (SD 9.8). The group with moderate or severe anxiety, compared to the group with minimal or mild anxiety, presented an association with lower maternal age (median 21.5 vs. 29.5 years, p=0.019), lower fetal umbilical vein blood flow (median 189.4 vs. 249.5 mL/min, p=0.047), and lower umbilical vein-corrected blood flow (median 68.5 vs. 84.9 mL/kg/min, p=0.038). CONCLUSION: Maternal anxiety may affect fetal circulation patterns in late pregnancy and is associated with reduced blood flow in the fetal umbilical vein. The underlying physiopathology needs further investigation.

Effects of maternal anxiety on fetal and maternal circulation.

OBJECTIVE: The aim of this study was to evaluate the association between maternal anxiety in the third trimester and changes in fetal and maternal circulation assessed by Doppler velocimetry. METHODS: This is a prospective, cross-sectional study. The inclusion criteria were good health, a singleton pregnancy, maternal age between 18 and 40 years, and gestational age between 34 and 40 weeks. Doppler measurements included mean uterine artery pulsatility index, fetal middle cerebral artery pulsatility index, peak of systolic velocity, umbilical artery, and umbilical vein. The Beck Anxiety Inventory questionnaire, validated for the Brazilian population, with 21 self-reported items, was applied. RESULTS: The study included 34 pregnant women, and 6 (17.7%) presented a total Beck Anxiety Inventory score showing moderate or severe maternal anxiety. The mean maternal age was 28.1 years (SD 5.7 years); the mean gestational age at interview was 36.5 weeks (SD 1.8 weeks), and the mean Beck Anxiety Inventory total score was 12.3 (SD 9.8). The group with moderate or severe anxiety, compared to the group with minimal or mild anxiety, presented an association with lower maternal age (median 21.5 vs. 29.5 years, p=0.019), lower fetal umbilical vein blood flow (median 189.4 vs. 249.5 mL/min, p=0.047), and lower umbilical vein-corrected blood flow (median 68.5 vs. 84.9 mL/kg/min, p=0.038). CONCLUSION: Maternal anxiety may affect fetal circulation patterns in late pregnancy and is associated with reduced blood flow in the fetal umbilical vein. The underlying physiopathology needs further investigation.

Fetal thymus in growth-restricted fetuses due to placental insufficiency.

OBJECTIVE: The aim of this study was to assess fetal thymus size by ultrasound in growth-restricted fetuses due to placental insufficiency and compare to high-risk and low-risk pregnancy fetuses with normal placental function. METHODS: This is a nested case-control study of pregnant women followed up at a university hospital (July 2012 to July 2013). In all, 30 pregnant women presenting small fetuses for gestational age (estimated fetal weight p95) were compared to 30 high-risk and 30 low-risk pregnancies presenting normal Doppler indices. The thymus transverse diameter and perimeter were converted into zeta score according to the normal values for gestational age. Head circumference and femur length were used to calculate ratios. RESULTS: Fetal thymus were significantly lower in pregnancies with placental insufficiency when compared to high-risk and low-risk pregnancies presenting, respectively, transverse diameter zeta score (-0.69±0.83 vs. 0.49±1.13 vs. 0.83±0.85, p<0.001) and P zeta score (-0.73±0.68 vs. 0.45±0.96 vs. 0.26±0.89, p<0.001). There was also a significant difference (p<0.05) in the ratios among the groups: pregnancies with placental insufficiency (TD/HC=0.10, P/FL=1.32, and P/HC=0.26), high-risk pregnancies (TD/HC=0.11, P/FL=1.40, and P/HC=0.30), and control group (DT/HC=0.11, P/FL=1.45, and P/HC=0.31). CONCLUSION: Fetal thymus size is reduced in growth-restricted fetuses due to placental insufficiency, suggesting fetal response as a consequence of the adverse environment.

Fetal thymus in growth-restricted fetuses due to placental insufficiency

SUMMARY OBJECTIVE: The aim of this study was to assess fetal thymus size by ultrasound in growth-restricted fetuses due to placental insufficiency and compare to high-risk and low-risk pregnancy fetuses with normal placental function. METHODS: This is a nested case-control study of pregnant women followed up at a university hospital (July 2012 to July 2013). In all, 30 pregnant women presenting small fetuses for gestational age (estimated fetal weight <p10) due to placental insufficiency (umbilical artery Doppler >p95) were compared to 30 high-risk and 30 low-risk pregnancies presenting normal Doppler indices. The thymus transverse diameter and perimeter were converted into zeta score according to the normal values for gestational age. Head circumference and femur length were used to calculate ratios. RESULTS: Fetal thymus were significantly lower in pregnancies with placental insufficiency when compared to high-risk and low-risk pregnancies presenting, respectively, transverse diameter zeta score (-0.69±0.83 vs. 0.49±1.13 vs. 0.83±0.85, p<0.001) and P zeta score (-0.73±0.68 vs. 0.45±0.96 vs. 0.26±0.89, p<0.001). There was also a significant difference (p<0.05) in the ratios among the groups: pregnancies with placental insufficiency (TD/HC=0.10, P/FL=1.32, and P/HC=0.26), high-risk pregnancies (TD/HC=0.11, P/FL=1.40, and P/HC=0.30), and control group (DT/HC=0.11, P/FL=1.45, and P/HC=0.31). CONCLUSION: Fetal thymus size is reduced in growth-restricted fetuses due to placental insufficiency, suggesting fetal response as a consequence of the adverse environment.

Unplanned pregnancy in Brazil: national study in eight university hospitals / Gravidez não planejada no Brasil: estudo nacional em oito hospitais universitários

ABSTRACT OBJECTIVE To estimate the prevalence of unplanned pregnancy in eight public university hospitals, distributed in the five regions that make up Brazil. METHODS A secondary analysis of a national multicenter cross-sectional study, carried out in eight public university hospitals between June 1 and August 31, 2020, in Brazil. Convenience sample including women who gave birth within sixty consecutive days and met the following criteria: over 18 years old; gestational age over 36 weeks at delivery; with a single and live newborn, without malformations. RESULTS Sample composed of 1,120 postpartum women, of whom 756 (67.5%) declared that the pregnancy had not been planned. The median prevalence of unplanned pregnancy was 59.7%. The prevalence of unplanned pregnancy across hospitals differed significantly: Campinas (54.8%), Porto Alegre (58.2%), Florianópolis (59%), Teresina (61.2%), Brasília (64.3%), São Paulo (64.6%), Campo Grande (73.9%) and Manaus (95.3%) (p < 0.001). Factors significantly associated with unplanned pregnancy were maternal age, black color, lower family income, greater number of children, greater number of people living in household, and not having a partner. CONCLUSION In the studied sample, about two thirds of the pregnancies were declared as unplanned. The prevalence of unplanned pregnancies was related to social and demographic factors and varied significantly across the university hospitals evaluated.

RESUMO OBJETIVO Estimar a prevalência de gestação não planejada (GNP) em oito hospitais públicos universitários, distribuídos nas cinco regiões que compõem o Brasil. MÉTODOS Análise secundária de um estudo transversal multicêntrico nacional, realizado em oito hospitais universitários públicos, entre 1º de junho e 31 de agosto de 2020, no Brasil. Amostra por conveniência incluindo mulheres que deram à luz em período de sessenta dias consecutivos e atenderam aos seguintes critérios: maiores de 18 anos; idade gestacional acima de 36 semanas no parto; com recém-nascido único e vivo, sem malformações. RESULTADOS Amostra composta por 1.120 puérperas, das quais 756 (67,5%) declararam que a gravidez não tinha sido programada. A mediana da prevalência de GNP foi de 59,7%. Observou-se diferença significativa na prevalência de GNP entre os hospitais: Campinas (54,8%), Porto Alegre (58,2%), Florianópolis (59%), Teresina (61,2%), Brasília (64,3%), São Paulo (64,6%), Campo Grande (73,9%) e Manaus (95,3%) (p < 0,001). Foram fatores significativamente associados a GNP a idade materna, cor negra, menor renda familiar, maior número de filhos, maior número de pessoas convivendo em casa e não ter parceiro. CONCLUSÃO Na amostra estudada, cerca de dois terços das gestações foram declaradas como não programadas. A prevalência de gestação não planejada teve relação com fatores sociais e demográficos e variou significativamente entre os hospitais universitários avaliados.

Nonpharmacological Methods to Reduce Pain During Active Labor in A Real-life Setting / Métodos não farmacológicos para reduzir a dor durante o trabalho de parto ativo em um cenário da vida real

Abstract Objective To evaluate the association between pain intensity in the active phase of the first stage of labor with the use or not of nonpharmacological methods for pain relief in a real-life scenario. Methods This was an observational cross-sectional study. The variables analyzed were obtained by a questionnaire with the mothers (up to 48 hours postpartum) to investigate the intensity of pain during labor using the visual analog scale (VAS). The nonpharmacological pain relief methods routinely used in obstetric practice were evaluated by consulting medical records. The patients were separated into two groups: Group I - patients who did not use nonpharmacological methods for pain relief and Group II -patients who used these methods. Results A total of 439 women who underwent vaginal delivery were included; 386 (87.9%) used at least 1 nonpharmacological method and 53 (12.1%) did not. The women who did not use nonpharmacological methods had significantly lower gestational age (37.2 versus 39.6 weeks, p < 0.001) and shorter duration of labor (24 versus 114 min, p < 0.001) than those who used the methods. There was no statistically significant difference in the pain scale score using the VAS between the group that used nonpharmacological methods and the group that did not (median 10 [minimum 2- maximum 10] versus 10 [minimum 6-maximum 10] p = 0.334). Conclusion In a real-life setting, there was no difference in labor pain intensity between the patients who used nonpharmacological methods and those who did not use them during the active phase of labor.

Resumo Objetivo Avaliar a associação da intensidade da dor na fase ativa da dilatação do parto em mulheres de acordo com a utilização ou não de métodos não farmacológicos para alívio da dor em cenário de vida real. Métodos Trata-se de um estudo observacional de corte transversal. As variáveis analisadas foram obtidas através de questionário com as puérperas (até 48 horas pós-parto) investigando a intensidade da dor no parto pela escala visual analógica (EVA). As medidas não farmacológicas de alívio da dor, utilizadas rotineiramente na prática obstétrica, foram avaliadas pela consulta aos prontuários. As pacientes foram separadas em dois grupos: Grupo I - pacientes que não utilizaram medidas não farmacológicas para alívio da dor e Grupo II - pacientes que utilizaram estas medidas. Resultados Foram incluídas 439 mulheres que tiveram parto vaginal, sendo que 386 (87,9%) utilizaram, pelo menos, uma medida não farmacológica e 53 (12,1%) não utilizaram. As mulheres que não utilizaram as medidas não farmacológicas apresentaram idade gestacional significativamente menor (37,2 versus 39,6 semanas, p < 0,001) e menor duração do trabalho de parto (24 versus 114 minutos, p < 0,001) quando comparadas às que utilizaram as medidas. Não houve diferença estatisticamente significativa na pontuação da escala da dor pela EVA de acordo com a categorização pelo uso ou não de métodos não farmacológicos (mediana 10 [mínimo 2-máximo 10] versus 10 (mínimo 6-máximo 10), p = 0,334]. Conclusão Em cenário de vida real, as pacientes submetidas aos métodos não farmacológicos não apresentaram diferença em relação à intensidade da dor quando comparadas às que não os utilizaram durante a fase ativa do trabalho de parto.

Obstetric simulation for undergraduate medical education: how to improve students' self-confidence and expectation according to gender

SUMMARY OBJECTIVE: The aim of this study was to evaluate the effects of obstetric simulation training on undergraduate medical students to improve their self-confidence. METHODS: Fifth-year undergraduate medical students were invited to a 2-week course of simulation in obstetrics during their clerkship. The sessions included were as follows: (1) care for the second and third periods of childbirth, (2) partograph analysis and pelvimetry, (3) premature rupture of membranes at term, and (4) diagnosis and management of third-trimester bleeding. Before the first session and at the end of the training period, a questionnaire about self-confidence in obstetric procedures and skills was applied. RESULTS: A total of 115 medical students were included, of whom 60 (52.2%) were male and 55 (47.8%) were female. Comparing initial and final scores, the median results of the subscales "comprehension and preparation" (18 vs. 22, p<0.001), "knowledge of procedures" (14 vs. 20, p<0.001), and "expectation" (22 vs. 23, p<0.01) were significantly higher at the end of the training period in all items of the questionnaire than in the beginning. Differences were found based on the students' gender, i.e., female students had a significantly higher sum of scores than the male students in the initial subscale for "expectation" (median, 24 vs. 22, p<0.001) and "interest" (median, 23 vs. 21, p=0.032), and a higher sum of scores in the subscale for "expectation" (median, 23 vs. 21, p=0.010) in the final questionnaire. CONCLUSION: Obstetric simulation enhances the improvement of students' self-confidence in understanding both the physiology of childbirth and the obstetric care procedures. Further studies are needed to understand the influence of gender on obstetric care.

An enlarged fetal thymus may be the initial response to intrauterine inflammation in pregnant women at risk for preterm birth

SUMMARY OBJECTIVE: Fetal thymus involvement in prematurity has been studied, and this study aimed to evaluate its relationship with short cervix and amniotic fluid sludge in the second trimester of pregnancy. METHODS: In this prospective cross-sectional study, 79 pregnant women (19+0 to 24+6 weeks) were included, and cervical length and the presence or absence of amniotic fluid sludge were evaluated. In the three-vessel view of the fetal thorax, the thymus was identified, and its perimeter and transverse diameter were measured and transformed to a zeta score based on gestational age. RESULTS: Data from 22 women with short cervix (<25 mm) and 57 patients with normal cervix (≥25 mm) were analyzed. The transverse diameter of the fetal thymus was significantly greater in the short cervix group compared to that of the normal cervix group (z-score 2.708 vs. −0.043, p=0.003). There were no significant differences in the perimeter (z-score −0.039 vs. −0.071, p=0.890) or the transverse diameter (z-score 1.297 vs. −0.004, p=0.091) of the fetal thymus associated with the presence (n=21) or absence of sludge (n=58). CONCLUSION: A short cervix is associated with an increased transverse diameter of the fetal thymus during the second trimester of gestation.