INTRAOCULAR-PRESSURE AND PREGNANCY - A COMPARISON BETWEEN NORMAL AND OCULAR HYPERTENSIVE SUBJECTS

Decrease in intraocular pressure (IOP) during pregnancy has been repor ted by previous studies, but these studies have concentrated on the la st trimester of pregnancy or one reading per trimester. Moreover, IOP changes during pregnancy in ocular hypertensive subjects have never be en described. Therefore, the present study was planned to determine IO P throughout the pregnancy, in both normal and ocular hypertensive sub jects. Intraocular pressure was measured at six-week intervals through out the pregnancy in 44 normal and 32 ocular hypertensive women. Intra ocular pressure was also measured in 44 normal and 32 ocular hypertens ive non-pregnant controls of the same age group. IOP measurements were taken with the Goldmann applanation tonometer. In normal subjects, IO P decreased significantly at the 18(th) week (p<0.05). The IOP differe nces between first and second (p<0.05) and second and third (p<0.01) t rimesters of pregnancy were significant. In these subjects, pregnancy decreased IOP by 19.6%. About 35% of total decrease occurred between 1 2(th) and 18(th) weeks of pregnancy. In ocular hypertensive subjects, IOP decreased significantly at the 24(th) week (p<0.05). The IOP diffe rences between second and third (p<0.001) trimesters of pregnancy were significant. In these subjects, pregnancy decreased IOP by 24.4%. Abo ut 61% of total decrease occurred between 24(th) and 30(th) weeks of p regnancy. In both groups, decreases in IOP were independent of systoli c and diastolic blood pressures, body weight, height, and number of pr evious pregnancies. With advancing pregnancy, intraocular pressure dec reases. The higher decrease in ocular hypertensive subjects may be due to their higher level of ocular pressure. In ocular hypertensive subj ects, pregnancy can decrease intraocular pressure np to a level of nor mal limit.