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Objective To investigate the serum 25-hydroxy vitamin D concentrations and related factors in early pregnancy. Methods Plasma was collected in the first trimester from 23 396 pregnant women to inves-tigate the vitamin D level, and its distribution and differences in different age, body maxx index ( BMI) and seasons between primipara and multipara. Preterm birth was used as an indicator of clinical outcomes. Vitamin D concentrations were measured using chemiluminescence microparticle immunoassay. Results 25-hydroxy vi-tamin D level was 42. 0 (17. 6-76. 6) nmol/L in totally 23 396 pregnant women with early pregnancy, and 5% and 95% percentile sites of vitamin D level were 20. 2 nmol/L and 70. 7 nmol/L respectively. There were 18 170 (77. 7%) primiparas and 5 226 (22. 3%) multiparas, with the mean age of 30. 0 (24. 0-38. 0) years and BMI of 20. 7 (16. 5-27. 6) kg/m2. The number of cases detected in spring (March, April and May), summer (June, July and August), autumn (September, October and November months) and winter (Decem-ber, January and February) were 5 878, 5 554, 5 974, and 5 990, respectively, and the vitamin D levels were 40. 0 (29. 3, 52. 7) nmol/L, 46. 2 (35. 6, 57. 2) nmol/L, 43. 8 (33. 1, 54. 8) nmol/L and 37. 2 (26. 9, 49. 9) nmol/L respectively, with the difference in vitamin D levels statistically significant among the four seasons (P<0. 001). According to BMI, all pregnant women were divided into four groups as BMI<18. 5 kg/m2, 18. 5 kg/m2≤BMI≤23. 9 kg/m2, 24 kg/m2≤BMI≤27. 9 kg/m2, BMI≥28 kg/m2, and the levels of 25-hydroxy vitamin D were 43. 5 (30. 9, 56. 9) nmol/L, 42. 1 (30. 8, 53. 8) nmol/L, 39. 9 (30. 7, 50. 4) nmol/L and 39. 7 (30. 7, 49. 4) nmol/L respectively with the difference statistically significant among the four groups. The levels of vitamin D detected in pregnant women with age<25 years, 25~29 years, 30~34 years,≥35 years were 39. 1 ( 28. 4, 52. 3) nmol/L, 41. 3 ( 30. 1, 52. 9) nmol/L, 42. 4 ( 31. 2, 54. 1) nmol/L and 43. 8 (31. 9, 55. 7) nmol/L respectively and the difference was statistically significant (P<0. 001). The levels of 25-hydroxy vitamin D in primary and multiparas were 41. 6 (30. 2, 52. 9) nmol/L and 43. 5 (32. 5, 56. 8) nmol/L with the difference statistically significant (P<0. 001). Among women of different gestational age during childbirth, the differences in serum 25-hydroxy vitamin D in early pregnancy were not statistically significant (P=0. 121). The severe deficiency of vitamin D in early pregnancy was defined as serum level of 25-hydroxy vita-min D less than 5th level. There were statistical differences in the probability of severe vitamin D deficiency of dif-ferent ages, seasons and BMI between primiparas and multiparas. Conclusions Pregnant women of lower weight, lower age and primiparity have higher incidence of the severe vitamin D deficiency in early trimester of pregnancy. There is significant difference in 25-hydroxy vitamin D level among the different seasons (winter<spring<autumn<summer). Vitamin D level in early pregnancy is not associated with preterm birth.
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Objective:To determine the relationship between trimester-specific gestational weight gain and pregnancy outcome among women with twin pregnancies.Methods:A retrospective cohort study was conducted among Chinese women with twin pregnancies delivered from January 2013 to October 2015 in the International Peace Maternity & Child Health Hospital of China Welfare Institute.Gestational weight gain was compared between women with different progestational BMI.After the adjustment for age and progestational BMI,binary Logistic regression analysis was conducted to explore the relationship between gestational weight gain rate and gestational complications,premature birth,premature rupture of membrane and neonatal birth weight.Results:①A total of 472 subjects met the inclusion criteria.Rate of gestational weight gain were(0.41 ±0.15),(0.64 ±0.30) and (0.49 ±0.15) kg/week in Early,Mid-and Late-,and Whole of pregnancy respectively.②With regards to trimester-specific gestational weight gain,statistically significant associations were found between rate of weight gain and gestational hypertension and preterm birth (P ＜ 0.05).Those with faster gestational weight gain had higher rate of premature rupture of fetal membrane(P ＜ 0.05).And those with lower gestational weight gain had lower neonatal birth weight(P＜0.05).③After adjusting maternal age,progestational BMI and gestational age at delivery,the sum of twins' birth weight increased 25.21g,30.89g and 21.46g respectively when the maternal body weight increased 1kg during the whole pregnancy,in Early and Mid-pregnancy (P ＜ 0.001),and during in Late-pregnancy(P =0.001).Conclusions:Gestational weight gain among women with twin pregnancy are closely related with adverse pregnancy outcomes.The gestational weight gain rate in different gestation are of some predictive value for pregnancy outcomes.More research with long follow-up are needed to determine proper gestational weight gain for twin pregnancy suitable for Chinese women.
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Objective To assess the variations in different thyroid stimulating hormone(TSH) and free thyroxine (FT4) detection kits for evaluating thyroid function during pregnancy and to establish the corresponding normal reference ranges.Methods This study was based at the International Peace Maternity and Child Health Hospital affiliated to Shanghai Jiaotong University School of Medicine.A total of 200 pregnant women who visited the hospital between June,2011 and September,2012 were recruited in this study according to the National Academy of Clinical Biochemistry (NACB) criteria.Blood samples were sequentially collected from the women at the first (T1,9-12 weeks),second (T2,16-24 weeks) and third (T3,32-36 weeks) trimesters to determine the serum TSH and FT4 levels using four different detection kits (Siemens-C,Siemens-Ⅰ,Abott and Roche).A linear trend test was used to analyze serum TSH and FT4 levels with four different kits.A percentile range of P2.5 to P97.5 was used to establish the normal trimester-dependent reference ranges of TSH and FT4 levels for different detection kits.The Bootstrap method was used to compare the differences in the four reference ranges.Results Similar dynamic changes in TSH and FT4 levels during pregnancy were detected among the different kits (F=0.950,P=0.595; F=11.640,P=0.081,respectively).Among the four reference ranges of TSH,the Roche kit showed the most remarkable fluctuation during pregnancy,while Roche kit in the first trimester and Siemens C kit in the second and third trimesters showed larger fluctuations in reference ranges of FT4.More importantly,the reference ranges of TSH and FT4 showed significant variations among the four different kits in each trimester (TSH:T1:F=2 945.390,P ＜ 0.01; T2:F=2 826.260,P ＜ 0.01; T3:F=1 698.360,P ＜ 0.01.FT4:Tl:F=1 145.440,P ＜ 0.01; T2:F=2 260.240,P ＜ 0.01; T3:F=1 439.920,P ＜ 0.01).Conclusions TSH and FT4 measurement using four different commercial kits showed similar trimester-dependent dynamic changes.However,it is necessary to establish trimester-dependent and detection kit dependent normal reference ranges of TSH and FT4 for thyroid function evaluation for pregnant women.
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Objective To investigate the prevalence of hypothyroidism during the second trimester and its relationship with thyroid peroxidase antibody (TPOAb). Methods Two thousand one hundred and forty one pregnant women whose gestational age between 14 to 28 weeks,accepted their prenatal care at the outpatient clinic of International Peace Maternity & Child Health Hospital from March 1,2010 to July 31,2010 were enrolled into this study. Serum TPOAb,thyroidstimulating hormone (TSH) and free thyroxine (FT4) of these women were detected. Logistic regression model was used to analyze the risk factors of subclinical hypothyroidism and positive TPOAb,while Spearman rank correlation was used to analyze the relationship between the levels of TSH,FT4 and TPOAb. Results (1) Subclinical hypothyroidism was detected in 13.36％ (286/2141) patients. Isolated maternal hypothyroxinemia occurs in 0.14％ (3/2141) of pregnant women.No overt hypothyroidism patient was detected and 6.26％ (134/2141) of all pregnant women exhibited positive TPOAb(≥50 U/ml).(2) Positive rate of TPOAb in subclinical hypothyroidism group,isolated maternal hypothyroxinemia group and normal thyroid function group was 13.64％ (39/286),0/3 and 5.06％ (86/1701) respectively,and there was difference among the three groups (x2 =30.82,P＜0.01).The positive rate of TPOAb did not relate to fetal gender,maternal age,gestational age,gravidity and parity.(3) TPOAb had positive relationship with TSH level (r=0.12,P＜0.01),while did not relate to FT4 level (r=-0.04,P=0.09). (4) Positive TPOAb (OR 3.18,95％ CI:2.10-4.83,P＜0.01) and gravidity (OR=1.21,95％ CI:1.02-1.43,P=0.030)were risk factors of subclinical hypothyroidism. Conclusions Hypothyroidism is common during the second trimester. It is necessary to screen TPOAb in pregnant women as TPOAb is an independent and important predictor of subclinical hypothyroidism.
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Objective To investigate the changes of serum levels of sex hormone binding globulin (SHBG),free testosterone index (FTI) and insulin resistance; and to investigate the relationship among them and prevalence of gestational diabetes mellitus (GDM) and hypertensive disorder complicating pregnancy (HDP) in polycystic ovarian syndrome (PCOS) women during pregnancy. Methods Serum samples of 32 PCOS women and 32 non-PCOS women were collected during their gestational age from 12 to16 weeks.Serum levels of total testosterone,SHBG and insulin were detected.Free testosterone index (FTI) and homeostasis model assessment for insulin resistance (HOMA-IR) were calculated.Risk factors of GDM and HDP were analyzed by stepwise logistic regression.Data of two groups were compared with t test or Chi square test. Results Serum fasting insulin [(8.0±1.5) mU/L vs (7.1±1.5) mU/L,t=2.32,P＜0.05],FTI [0.96 (0.52-1.41) vs 0.61 (0.40-0.79),t=3.02,P＜0.05],HOMA-IR levels [1.53±0.32 vs 1.36±0.36,t=2.04,P＜0.05] and total testosterone [2.95 (1.61-4.40) nmol/L vs 2.15 (1.50-2.80) nmol/L,t=2.55,P＜0.05] were higher in PCOS group than in control group; and SHBG level [325 (312-355) nmol/L vs 360 (347-373) nmol/L,t=4.13,P＜0.05] was lower in PCOS group than in control group.Cesarean section rate (84％ vs 50％,x2 =8.58,P＜0.01) and HDP incidence (25％ vs 3％,x2=4.65,P＜0.05) were higher in PCOS group than in control group. SHBG level [(293 ±42) nmol/L] of PCOS women who complicated with GDM (n=6) was significantly lower than that [(333±40) nmol/L] of those who did not (n=26),t=2.22,P＜0.05.Serum total testosterone [(4.34±1.29)vs (2.49±1.44) nmol/L,t=3.23,P＜0.05] and FTI [1.42±0.52 vs 0.81±0.59,t=2.61,P＜0.05] were significantly higher in PCOS women complicated with HDP (n=8) than those of the PCOS women who did not (n=24).Stepwise logistic regression analysis showed that SHBG was the risk factor of GDM (OR=0.98,95％CI:0.96～1.00,P＜0.05); FTI was the risk factor of HDP in PCOS women (OR=5.53,95％CI:1.20～25.61,P＜0.05). Conclusions FTI and SHBG levels could be predictors for GDM and HDP in PCOS women during their pregnancies.