Thyroid hormones in pregnancy and preeclampsia

There is a state of hypothyroxinemia in normal pregnancy and in preeclampsia, when biochemically raised TSH occurs. Identification of changes in thyroid hormones in preeclampsia might be of help in preventing the occurrence of preeclampsia.

The present study was carried out in a hundred women with preeclampsia, 100 age- and parity matched normotensive pregnant women and 50 age-matched healthy non-pregnant women. Thyroid hormones [total T3,T4 and TSH], serum albumin and uric acid were analyzed in these subjects.

Women with preeclampsia had higher TT3, TT4 levels as compared to non pregnant women [p<0.05], but preeclamptic TT3, TT4 levels were lower compared to normotensive pregnant women [p<0.05, p<0.01]. TSH levels were higher in both preeclamptic & normotensive pregnant women compared to nonpregnant women [p<0.001] and levels were lower in normotensive pregnant women as compared to nonpregnant women [p<0.001]. A significant negative correlation was observed between birth weight and TSH levels [r=-0.296, p<0.001] serum albumin and TSH levels in preeclamptic women [r=-0.781, p<0.01]. Also, a significant positive correlation was observed between birth weight and albumin [r=0.298, p<0.001]; birth weight and serum uric acid levels [r=-0.46, p<0.01], and serum albumin and TT3 & TT4 levels [r=0.409 & r=0.35, p<0.01 respectively].

These findings indicate that there is state of hypothyroxinemia in normal pregnancy and in preeclampsia. Identification of changes in thyroid hormones in preeclampsia might be of help in preventing the occurrence of preeclampsia.