Material and Methods
The study was conducted between October 2009 and March 2010, in the Indira Gandhi Govt. Medical College, Nagpur, India. Subjects were from Nagpur region, an iodine sufficient area, based on data available from Urinary Iodine Excretion studies, conducted in the region15. The study group (n=32) comprised of young healthy, primigravida full term pregnant females, aged 18-32 (23.46±3.07) years who were in labor, admitted at the institution for delivery and expected to have spontaneous full term vaginal delivery. Thirty-two age matched (23±2.8years), normal healthy pregnants, primigrivida, attending ANC-OPD in the Obstetrics and Gynecology Department of the institution, made up the control group. The protocol was approved by the institutional ethics committee and following selection of subjects, informed consent was obtained from them. Serum TT3, TT4 and serum TSH levels were assessed in both groups; to do this, 3ml of Blood was, in turn, drawn from the antecubital vein. Samples were collected with all aseptic precautions, using sterile needles and syringes in plain sterile bulb. In the controls, samples were obtained during their routine ANC-OPD visit, while in the study group, samples were taken on three occasions: Phase A (during stage I of labor – from initiation of labor pains to full dilatation of cervix); phase B (2 hours after stage III of labor, i.e., after delivery of placenta & membranes) and phase C: (24-48 hours after delivery – immediate puerperium). Samples were kept undisturbed for 30 minutes and centrifuged at
3000rpm for 15 minutes. Serum was separated; we opted for use of monoclonal antibody in ELISA Test, which eliminates cross reactivity with other hormones. Quantitative determination of TT3 & TT4 concentration was carried out using ELISA. Quantitative deter-mination of TSH was
carried out using streptavidin biotin technology, which is a solid phase sandwich ELISA method. Results of normal values obtained for healthy adults were follows: TT3: 0.52-1.85 ng/mL; TT4: 4.8-11.5 μg/dl, and serum TSH: 0.39-6.6 micro IU/mL.