title: Thyroid function during controlled ovarian hyperstimulation as part of in vitro fertilization.
abstract: OBJECTIVE
  To determine the exact nature and timing of alterations in thyroid function throughout controlled ovarian hyperstimulation (COH).
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  University fertility clinic.
  
  
  METHODS
  Fifty-seven women undergoing COH as part of planned in vitro fertilization.
  
  
  METHODS
  None.
  
  
  METHODS
  Timing and magnitude of change in serum thyroid hormones, including TSH, total and free T(4), E(2), and thyroxine-binding globulin (TBG), measured at six time points from before stimulation to 2 weeks after serum pregnancy test.
  
  
  RESULTS
  Geometric mean serum TSH increased during stimulation, peaking 1 week after hCG administration compared with baseline (2.44 vs. 1.42 mIU/L), as did free T(4) (1.52 vs. 1.38 ng/dL) and TBG (32.86 vs. 21.52 μg/mL). Estradiol levels increased, peaking at hCG administration (1743.21 vs. 71.37 pg/mL). Of 50 women with baseline TSH ≤ 2.5 mIU/L, 22 (44.0%) had a subsequent rise in TSH to >2.5 during or after COH. The pattern of change over time in TSH concentrations was significantly influenced by baseline hypothyroidism and whether pregnancy was achieved.
  
  
  CONCLUSIONS
  COH led to significant elevations in TSH, often above pregnancy appropriate targets. These findings were particularly evident in women with preexisting hypothyroidism and may have important clinical implications for screening and thyroid hormone supplementation.
authors.affiliation: Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA. cgracia@obgyn.upenn.edu
authors.forename: Clarisa R
authors.initials: CR
authors.lastname: Gracia
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Morse
authors.forename: Grace
authors.initials: G
authors.lastname: Chan
authors.forename: Samantha
authors.initials: S
authors.lastname: Schilling
authors.forename: Maureen
authors.initials: M
authors.lastname: Prewitt
authors.forename: Mary D
authors.initials: MD
authors.lastname: Sammel
authors.forename: Susan J
authors.initials: SJ
authors.lastname: Mandel
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D004958:Estradiol / Q000097:blood; D005260:Female; D005300:Fertility Agents, Female / Q000008:administration & dosage*; D005307:Fertilization in Vitro; D006801:Humans; D007037:Hypothyroidism / Q000097:blood / Q000150:complications*; D007246:Infertility / Q000097:blood / Q000150:complications / Q000628:therapy*; D016014:Linear Models; D008875:Middle Aged; D010060:Ovulation / Q000187:drug effects*; D010062:Ovulation Induction; D015143:Philadelphia; D011247:Pregnancy; D018873:Pregnancy Rate; D011446:Prospective Studies; D013961:Thyroid Gland / Q000187:drug effects* / Q000378:metabolism; D013963:Thyroid Hormones / Q000097:blood*; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood; D056825:Thyroxine-Binding Globulin / Q000378:metabolism; D013997:Time Factors; D014284:Triiodothyronine / Q000097:blood
chemical_list: D015415:Biomarkers; D005300:Fertility Agents, Female; D013963:Thyroid Hormones; D056825:Thyroxine-Binding Globulin; D014284:Triiodothyronine; D004958:Estradiol; D013972:Thyrotropin; D013974:Thyroxine