Volume 166 Number I, Part 2

543 RELATION OF TOTAL MATERNAL WATER (TMW). ARTERIAL PRESSURE (AP) AND PROGESTERONE (PROG) TO NEWBORN WEIGHT (BW). F Mardones­Santanderx

• G Salazarx• F Mardones-Restat'. J

Alvearx• GJ Valenzuela. INTA. U. Chile. Santiago and Ob Gyn. Lorna Linda U .• Santiago and California,

Maternal factors that influence have been studied separately. and usually in small samples. We decided to assess the relation of TMW. maternal weight. ponderal index. plasma volume. AP. Hcto. PROG. aldosterone and estradiol to BW. We determined those parameters in a total of 114 normal pregnant women. with a wide range of maternal weights. during the last part of pregnancy. Mean.±. SO were TMW= 33.08.±. 5.5. PROG 182 .±. 6a,7 ng/ mi. sytolic AP 113.±. 6.4 and diastolic AP 69.07 .±. 8.6 mm Hg, The data was analyzed by logistic regression, BW was positively correlated to TMW {r=0.311. PROG (r=.19) and AP (r=.26)' Other classical factors (maternal weight. etc.) became important only when the effect of TMW was removed from the analysis. We concluded that the normal mechanism that produce maternal water retention is important in determining BW. The exact mechanism of how these factors influence BW remains unclear at this time.

544 A COMPARISON OF THE CHANGES IN PLATELET SIZE AND PLATELET COUNT IN PREECLAMPSIA. J J Walker, A D Cameron, C

Singeri', C Fraseri'. Perinatal Research Unit, Glasgow Royal Matern~y Hosp~al, Glasgow, Scotland, UK.

Platelet count is known to fall in preeclampsia. We have previously shown that rising platelet size may precede the drop in platelet count. The purpose of this study was to investigate the relationship between platelet count and platelet size in patients who were preeclamptic. Three hundred and twenty six primigravid patients w~h moderate or severe preeclampsia were studied. Blood was drawn and the platelet count and mean platelet volume were calculated using a Couner Counter S.

... Platelet

Count ... ... 2 ..

, ..

• • , . , 2 14 ,. Maan Platalet Volume

There was a significant negative correlation between the platelet count and the mean platelet volume (r=-O.5, p<O.OOl). Conclusions. These resuns imply that changes in platelet size is associated with a fall in platelet count. However, the count will often remain in the normal range.

spa Abstracts 423

545 IlATEIIIAL FETAl Ia.IICOSE _IEIIT _ R.ShHfman, G.ICUO~ J.Jo.i ... vich~. Dept_ Db/Gyn. llethodi.lt and Irookdale Hosps •• B'klyn. NY

Maternal glucose (MG) is thought to cross the placenta by facilitated dif­fusion. Evaluation of maternal-fetal glucose gradients (Delta) was done at term. KETHODS: 74 patients with single­ton pregnancies and no known diabetes had MG and cord venous and arterial glucose (VG,AG) drawn at delivery. Delta (MG-VG) was calculated as well as FDelta (VG-AG). Correlation coefficient and t-tests were performed using the SPSS program. RESULTS: Pearson rand P values are listed below. When comparing MG~120 to MG>120, there was a highly significant difference. No correlation was found with neonatal weight •

!!!ilY!! IIl/AG !!l!.l!!.£!.!I ~ r: .8626* .7468* .5261* .4034* *P<.OOI

~ ~ Delta FOel ta MG~120: n.9:t1.4 63.2!1.9 17.1!1.1 1.7!1.2 MG>120: 107.5!2.8* B9_0!4* 27.5!3.7* 1S_5!1.7* CONCLUSIONS: At higher MG levels there is a significantly greater Delta, sug­gesting a placental regulatory mechan­ism for varying glucose delivery to the fetus. Similarly, the amount of glucose utilized by the fetus (proport­ional to Fdelta) may also depend on maternal levels.

546 EFFICACY OF PREINDUCTION "OILAPAN" ON LOWERING THE CESAREAN SECTION RATE. GJ Gilson, JF Smith, LB Curet, LA Izquierdo, MS Chatteljee, GM Joffe", GO Del VaIle". University of New Mexico Hospital, Albuquerque, New Mexico. The objective of the current study was to investigate whether or not " OILAPAN " (polyacrylatehydrogel) intracervicaJhydroscopic dilators (OIL) would have an effect on the outcome of oxytocin induction of labor at term. Methodology entailed study of 59 term gravidas randomized to receive preinduction DIL or no pretreatment. All subjects had Bishop scores of 4 or less. Nulliparas and mUltiparas were equally represented in the two groups. Results revealed that, compared to controls, the DIL group exhibited a significant change in Bishop scores (2.8±1.0 to 5.0±2.0, p'::;' .0001), but no significant difference in induction to delivery interval (OIL:19.2±9.7 hours, control: 14.9±5.6 hours). Of more importance, there was no significant difference in cesarean section rate (OIL:!3 of 29[44.8%], control: 8 of 30[26.7%]), although there was a tendency for OIL subjects to have a more advanced dilatation when they underwent abdominal delivery. Infant weights (OIL: 3118±721, control: 2981±7!3) and Apgars (OIL:8.6±0.9, control: 8.5±0.8) were not significantly different and no adverse maternal or fetal effects could be attributed to use of the device. Conclusion: Preinduction cervical ripening with OIL does not appear to appreciably lower the cesarean section rate.