A Comparative Study Between First And Second Trimester Multifetal Pregnancy Reduction

OBJECTIVE:The comparative study between first-trimester multifetal pregnancy reduction and second-trimester multifetal pregnancy reduction was undertaken to investigate the safety of multiple pregnancy fetal reduction, effectiveness,time of the operation,selection of the reduced fetuses,optimal number of remained fetuses and ethical issues faced in clinical experience.So we can find a best way to improve the multiple pregnancy outcomes.METHODS:We conducted a comparative study that comprised all 33 cases that accepted first-trimester MFPR in the reproductive center of Shandong Provincial Hospital(Group 1)and all 48 cases that accepted second-trimester MFPR in the obstetric department of Shandong Provincial Hospital(Group 2). The first-trimester MFPR are performed before 12 weeks of pregnancy and the second-trimester MFPR are performed between 12-24 weeks of pregnancy.All of theses cases were performed and have been followed up between January 2001 October 2007.RESULTS:1.In Group 1,The study population comprised 33 patients:14 patients(42.42%) occurred complications.Among them,there were 2 patients(6.06%)with threatened abortion,6 patients(18.18%)with premature rupture of membranes,2 patients(6.06%)with hypertension during pregnancy,2 patients(6.06%)with high fever after the procedure,0 patients(0%)with abnormal blood coagulation,2 patients(6.06%)with hyperemesis gravidarum.2.In Group 2,The study population comprised 48 patients:15 patients(31.25%) occurred complications.Among them,there were 3 patients(6.25%)with threatened abortion,7 patients(14.58%)with premature rupture of membranes,1 patients(2.08%)with hypertension during pregnancy,2 patients(4.17%)with high fever after the procedure,1 patients(2.08%)with abnormal blood coagulation,1 patients(2.08%)with hyperemesis gravidarum.3.The overall pregnancy complication rate was no statistical significance between Group 1 and 2.And There were no significant difference in aspect of threatened abortion,premature rupture of membranes,hypertensive disorders of pregnancy,infection or high fever,blood coagulation abnormalities,and hyperemesis gravidarum.4.In Group 1,in 33 cases,there were 6 cases(18.18%)abortion,27 cases (81.82%)successful delivery.A total of 51 newborns were deliveried.The average gestational age at birth was 36.58±0.97.Among the successful deliveried cases,1 patients(3.70%)pregnanted between 28 and 29⁺⁶weeks, 3 patients(11.11%)pregnanted between 30-33⁺⁶weeks,9 patients(33.33%) pregnanted between 34-36⁺⁶weeks,14 patients(51.85%)pregnanted after 37 weeks.The were 7 patients(25.93%)spontaneous labored and there were 20 cases(74.07%)accepted cesarean section.The average weight of newborns was 2655.29±185.25g.Among them,there was 1(1.96%)newborn's weight smaller than 1000g,2(3.92%)newborns' weight between 1000-1499g,4 (7.84%)newborns' weight between 1500-1999g,15(29.41%)newborns' weight between 2000-2499g,29(56.86%)newborns' weight more than 2500g. Among them,18(35.29%)newborns transferred into paediatric department for further treatment,and 4(7.84%)of them died.0 newborn was with abnormal appearance.5.In Group 2,in 48 cases,there were 8 cases(16.67%)abortion,40 cases (83.33%)successful delivery.A total of 74 newborns were deliveried.The average gestational age at birth was 36.33±0.78.Among the successful deliveried cases,1 patients(2.5%)pregnanted between 28 and 29⁺⁶weeks,6 patients(15%)pregnanted between 30-33⁺⁶weeks,12 patients(30%) pregnanted between 34-36⁺⁶weeks,21 patients(52.5%)pregnanted after 37 weeks.The were 10 patients(25%)spontaneous labored and there were 30 cases(75%)accepted cesarean section.The average weight of newborns was 2433.38±150.01g.Among them,there was 0 newborn's weight smaller than 1000g,6(8.11%)newborns' weight between 1000-1499g,9(12.16%) newborns' weight between 1500-1999g,20(27.03%)newborns' weight between 2000-2499g,39(52.70%)newborns' weight more than 2500g. Among them,25(33.78%)newborns transferred into paediatric department for further treatment,and 6(8.11%)of them died.One fetus was was diagnosed as hydrocephalus with ultrasound,and the parients refused MFPR and died after seven months.6.The successful delivery rate and abortion rate were no statistical significance between Group 1 and 2.There were no significant difference in average gestational age and mode of delivery.There were no significant difference in in newborns' body weight.The neonatal hospitalization rate and perinatal mortality rate were no statistical significance between the two groups.CONCLUSIONS:1.First-trimester multifetal pregnancy reduction is a simple,well-targeted, secure,reliable,effective and minimally invasive method.It can reduce fetal numbers,in order to effectively improve the outcome of pregnancy,length gestational age,reduce pregnancy complications,improve the successful pregnancy rate,increase birth weight,and improve birth quality.2.Second-trimester multifetal pregnancy reduction is a simple,well-targeted, secure,reliable,effective and minimally invasive method.It can reduce fetal numbers,in order to effectively improve the outcome of pregnancy,length gestational age,reduce pregnancy complications,improve the successful pregnancy rate,increase birth weight,and improve birth quality.And this operation can effectively avoid fetus with appearance malformations or chromosomal abnormalities being born.3.The overall pregnancy complication rate was no statistical significance between Group 1 and 2.And There were no significant difference in aspect of threatened abortion,premature rupture of membranes,hypertensive disorders of pregnancy,infection or high fever,blood coagulation abnormalities,and hyperemesis gravidarum.4.The successful delivery rate and abortion rate were no statistical significance between Group 1 and 2.There were no significant difference in average gestational age and mode of delivery.There were no significant difference in in newborns' body weight.The neonatal hospitalization rate and perinatal mortality rate were no statistical significance between the two groups.5.We believe that first-trimester multifetal pregnancy reduction and second-trimester multifetal pregnancy reduction are the same safe and effective.Fetal reduction should be put into practice as soon as possible after prenatal diagnosis.6.How to choose the fetus been reduced? When we just want to reduce number of fetuses,we should choose fetuses near abdominal wall and at the bottom of uters,and the fetuses near the cervical is not good choices.When we want to reduce the abnormal fetuses,we should be distinguish the normal ones with the abnormal ones carefully.7.There maybe traffic branches between placental blood vessels of single-chorionic twins.So when we reduce one of them,necrosis substance may go into the other fetus through these traffic branches and induce the other one's death in a short time.So the fetal reduction to single-chorionic twins should be careful.8.The best number of fetuses retained is controversial now.Most multifetal pregnancy reduction reserve two fetuses.Of course,some medical reasons should be treated differently,such as double uterus,single-chorionic twins, threatened Premature before 30 weeks. 9.Just considering medical aspects only,MFPR is benefit for pregnant women and fetuses obviously.However,the influenses of fetal reduction in the ethical, psychological and etc,need further study.10.Limit the use of promoting ovulation drugs and reducing the number of transferred embryos are the key to solve the problem of multiple pregnancy.